BIOL 2401 Exam 1 Review Sheet (Chapter 1-3)
Chapter 1
Define anatomy and physiology and describe their subdivisions.
Anatomy: Study of the structure of body parts and their relationship to one another.
Subdivisions of anatomy:
● Gross or macroscopic anatomy: the study of large visible structures (can see with the
naked eye)
o Regional anatomy: looks at all structures in a particular area of the body
o System anatomy: looks at just one system of the 11 (ex: cardiovascular,
reproductive, urinary, nervous, etc.)
o Surface anatomy: looks at internal structures as they relate to overlying skin
(visible muscle masses or veins seen on surface)
● Microscopic anatomy: deals with structures too small to be seen by the naked eye.
o Cytology: microscopic study of cells
o Histology: microscopic study of tissues
●
Developmental anatomy: studies anatomical and physiological development throughout
life
o Embryology: study of developments before birth
* To study anatomy, one must know anatomical terms and be able to observe, manipulate, palpate, and
auscultate.
Physiology: Study of the function of body parts and how they work to carry out life sustaining activities.
Subdivisions of physiology:
● Based on organ systems (ex: renal or cardiovascular physiology)
● Focuses on cellular and molecular levels of the body.
● Looks at how the body’s abilities are dependent on chemical reactions in individual cells
* To study physiology, one must understand basic physical principles (ex: electrical currents (nervous
system), pressure, movement) as well as basic chemical principles
Name the different levels of structural organization that make up the human body, and
explain their relationships. (Slide 9)
Chemical level: atoms combined to form molecules.
● Subatomic particles; atoms; molecules; macromolecules
o Ex: protons, neutrons, electrons, hydrogden, Carbon, water, proteins
Cellular level: cells made of molecules; smallest units of life.
● Organelles: mitochondria, ribosomes, endoplasmic reticulum, etc.
Tissue level: consists of similar types of cells performing a specific function.
● 4 basic types:
1. Epithelium: covers & lines
2. Muscle: movement (aids locomotion)
3. Connective: support and protect
4. Nervous: transmit electric impulses
Organ level: made up of different types of tissues.
● Usually, 2 or more types of tissues
● 4 is more common.
Organ system level: consists of different organs that work closely together
Organismal level: made up of the organ systems, single complete individual.
Chemical (atoms form
molecules)
Cellular (made of
molecules)
Tissue (similar types of
cells)
Organ (made up of
different tissues >2)
Organ system (made up of
different organs)
Organismal (made up of
different organ systems to
make a single individual)
List the 11 organ systems of the body, identify their components, and briefly explain
the major function(s) of each system.
1. Cardiovascular:
a. Components: Heart, blood vessels
b. Function: BV transport blood, carries oxygen, CO2, nutrients, wastes. Heart pumps blood
2. Integumentary:
a. Components: Hair, skin, and nails.
b. Function: Skin Synthesizes Vitamin D. Protects deeper tissue from injury, houses
cutaneous receptors(pain,pressure) sweat oil glands
3. Skeletal:
a. Components: Bones, Joints.
b. Function: Protects & supports body organs. Blood cells formed within bones.
4. Muscular:
a. Components: Skeletal Muscles.
b. Function: Produces heat, Locomotion, & facial expressions
5. Nervous:
a. Components: Brain, Nerves, Spinal Cord.
b. Function: Control system and activates appropriate muscles and glands to internal &
external changes.
6. Endocrine:
a. Components: Pancreas, Thymus, Thyroid gland, Pineal Glands, Pituitary Gland, Adrenal
Gland, Ovary, Testes.
b. Function: Glands secrete hormones such as growth, reproduction, and nutrient use by
body cells.
7. Lymphatic:
a. Components: Red Bone Marrow, Thymus, Lymphatic Vessels, Thoracic Duct, Spleen,
Lymph Nodes.
b. Function: Picks up fluid leaked from BV and returns to blood. immune response mounts
an attack against foreign substance within body.
8. Respiratory:
a. Components: Nasal Cavity, Pharynx, Larynx, Trachea, Lung.
b. Function: Keeps blood supplied w/ oxygen & removes CO2. Occurs in Air sacs of lungs
9. Urinary:
a. Components: Kidney, Ureter, Urinary Bladder, Urethra.
b. Function: Eliminates waste from the body and regulates water,electrolyte,acid base
balance of food.
10. Reproductive System:
a. Male Reproductive System:
i.
Components: Testes, Penis, Scrotum, Prostate, Ductus Deferens.
b. Female Reproductive System:
i.
Components: Mammary Glands, Ovary, Uterine Tube,Uterus,Vagina
c. Function (for both male & female): Function for offspring.
11. Digestive System:
a. Components: Oral Cavity, Esophagus, liver, stomach, small intestine, Large Intestine,
Rectum, Anus.
b. Function: Breaks down food for distribution to body cells.
List the functional characteristics necessary to maintain life in humans.
1. Maintaining boundaries: Separation between internal and external environments must exist
(Plasma membrane separating cells) (skin separates organisms for environment
2. Movement: Muscular system allows movement (body parts via skeletal muscles) (of substance
via cardiac muscle, Blood, and smooth muscle digestion, urination)
3. Responsiveness: Sense and respond to stimuli (reflex. control of breathing rate)
4. Digestion: Breakdown of ingested food. followed by absorption of simple molecules into blood.
5. Metabolism: all chemical reactions occur in body cells.
a. Catabolism: breakdown of molecules
b. Anabolism: synthesis of molecules
6. Excretion: Removal of waist of wastes from metabolism and digestion
a. urea = breakdown of proteins
b. carbon dioxide = metabolism
c. feces = unabsorbed food
7. Reproduction: at the cellular level, reproduction involves division of cells for growth or repair.
At the Organism level, reproduction is the production of offspring.
8. Growth: increase size of body part of organism
List the survival needs of the body.
●
●
●
●
●
Nutrients
○ Chemicals for energy and cell building
■ Carbs: major source of energy
■ Proteins: needed for cell building
■ Fats: long-term energy storage
■ Minerals and Vitamins: involved in chemical reactions, as well as structural
purposes.
Oxygen
○ Essential for release of energy from foods
○ Body can survive only for a few minutes without oxygen
Water
○ Most abundant chemical in the body
○ Also fluid base for secretions and excretions
Normal Body Temperature
○ Fahrenheit: 98.6
○ Celsius: 37
Appropriate Atmospheric Pressure
○ Specific pressure of air is needed for adequate breathing and gas exchange in lungs
Define homeostasis and explain its significance.
Definition:
● Homeostasis is the maintenance of relatively stable internal conditions despite continuous
changes in environment (is the balance of the human body)
● Dynamic state of equilibrium, always readjusting as needed to maintain the balance.
Significance:
● Whole body works together in stable environment (Maintained by contribution of all organ
systems)
● Aids in maintaining balance, essential for internal equilibrium.
Additional information related to homeostatic controls:
★ Variables are factors that can change.
○ Blood sugar
○ Body temperature
○ Blood volume, etc.
★ These variables are controlled by 3 components:
1. Receptor (sensor): monitors the environment and responds to stimuli
2. Control center: determines set point at which variable is maintained, receives input from
receptor, and determines appropriate response.
3. Effector: receives output from control center, provides the means to respond, and the
response either reduces stimulus (negative feedback: correcting homeostasis, most used
feedback) or enhances stimulus (positive feedback).
Describe how negative and positive feedback maintain body homeostasis.
Negative Feedback:
● Most used feedback mechanism in the body.
● Response reduces or shuts off original stimulus.
○ Examples
■ Regulation of body temp (nervous system). Body temperature is regulated by a
negative feedback mechanism.
■ Regulation of blood glucose by insulin (endocrine system)
○ Examples of negative feedback:
■ Receptors sense increased blood glucose (blood sugar).
■ Pancreas (control center) secretes insulin to blood.
■ Insulin causes body cells (effectors) to absorb more glucose. decreases blood
sugar.
Positive Feedback:
● Not good on humans
● Response enhances or exaggerates original stimulus.
● May have an amplifying effect as feedback causes variables to continue in the same direction as
initial change.
● Usually controls infrequent events that do not require continuous adjustment.
○ Example:
■ Enhancement of labor contractions by oxytocin.
■ Platelet plug formation and blood clotting.
Describe the relationship between homeostatic imbalance and disease.
Disturbance of Homeostasis:
● Occurs when Homeostasis is disturbed.
● Increases risk of disease
● Contributes to changes associated with aging
○ (with age control systems become less efficient)
If Negative feedback mechanisms become overwhelmed, destructive positive feedback mechanisms may
take over, for example, Heart Failure.
Describe the anatomical position.
Body Erect, feet slightly apart, palms facing forward, thumbs outward (pointing away from body).
Use correct anatomical terms to describe body directions, regions, and body planes or sections.
Body Directional Terms:
Superior (Cranial): Above; toward the head end or upper part of a structure or the body.
● Head is Superior to the abdomen.
Inferior (Caudal): Below; Toward the head end or upper part of a structure or body.
● Navel is inferior to chin.
Anterior (ventral): Toward or at the front of the body
● breastbone is anterior to the spine.
Posterior (dorsal): Behind
● Heart is posterior to breastbone.
Medial: toward or at the midline. inner side.
● Heart is medial to the arm.
Lateral: Away from midline.
● Heart is medial to the arm.
Intermediate: Between medial and lateral structure
● Collarbone is intermediate between breastbone and shoulder.
Proximal: Closer to trunk of body
● Elbow is proximal to the wrist.
Distal: Farther from trunk of body
● Knee is distal to thigh.
Superficial (external): Toward body surface
● The skin is superficial to skeletal muscles.
Deep (Internal): Away from body surface, more internal.
● Lungs are deep to the skin.
Sagittal Plane: Divides vertically to right and left.
● Midsagittal-Perfect cut made midline.
● Parasagittal-Off centered cut
Regional Terms:
Regional terms designate specific areas within the body divisions.
• Axial:
o Head, neck, and trunk
• Appendicular:
o Limbs (legs and arms)
Body Planes:
Surfaces along which body or structures may be cut for anatomical study.
Three most common planes:
• Sagittal:
o Divides body vertically into right and left parts.
o Produces a sagittal section if cut along this plane.
▪ Midsagittal (median) plane: cut was made perfectly on midline.
▪ Parasagittal plane: cut was off-centered, not on mid-line.
• Frontal (coronal):
o Divides body vertically into anterior and posterior (front and back).
o Produces a frontal or coronal section.
• Transverse (horizontal):
o Divides body horizontally (90 degrees to vertical plane) into superior and inferior parts
(top and bottom).
o Produces a cross section.
Body Sections:
Cuts or sections made along a body plane.
• Named after plane, so a sagittal cut results in a sagittal section.
•
Oblique section:
o Result of cuts at angle other than 90 degrees to a vertical plane
Locate and name the major body cavities and their subdivisions and associated.
membranes, and list the major organs contained within them.
Dorsal Body Cavities (Posterior/Back):
• Protects fragile nervous system.
Subdivisions:
o Cranial cavity: encases the (brain)
o Vertebral cavity: encases the (spinal cord)
Ventral Body Cavities (Anterior/front):
• Houses internal organs (viscera) (Pericardium/heart. Serous membrane) (pleurae/lungs)
(peritoneum/abdominopelvic)
Subdivisions: separated by diaphragm
● Thoracic Cavity:
○ 2 Pleural cavities (each surround one lung)
○ Mediastinum: Pericardial cavity (surrounds esophagus &trachea)
○ Pericardial cavity: encloses heart
● Abdominopelvic cavity:
○ Abdominal cavity: contains stomach, intestines, spleen, and liver.
○ Pelvic cavity: contains urinary, bladder, reproductive organs, and rectum.
•
Membranes in ventral body cavity:
o Serosa (serous membrane)
▪ Thin, double layered membranes that cover surfaces in ventral body cavity
• Parietal serosa: lines internal body cavity walls
• Visceral serosa: covers internal organs (viscera)
▪ Double layers are separated by slit-like cavity filled with serous fluid.
▪ Fluid secreted by both layers of membrane.
•
•
•
Pericardium = heart
Pleurae = lungs
Peritoneum = abdominopelvic cavity
Name the four quadrants or nine regions of the abdominopelvic cavity and list
the organs they contain.
4 Quadrants:
1.
2.
3.
4.
Right Upper
Left Upper
Right Lower
Left Lower
9 Regions
1. Right Hypochondriac
a. Liver
b. Gallbladder
2. Right Lateral (lumbar Region)
a. Ascending colon of large intestine
3. Right Inguinal (iliac) region
a. Cecum
b. Appendix
4. Epigastric region
a. Stomach
5. Umbilical region
a. Small intestine
b. Transverse colon of large intestine
6. Public (hypogastric region)
a. Urinary Bladder
7. Left hypochondriac region
a. Diaphragm
b. Spleen
8. Left lateral (lumbar region)
a. Descending colon of large intestine
9. Left inguinal (iliac) region
a. Initial part of sigmoid colon
Additional information regarding body cavities:
• Smaller cavities:
o Oral and digestive cavities
o Nasal cavity
o Orbital cavity
o Middle ear cavities
• Not exposed to the environment:
o Synovial cavities: joint cavities
Chapter 2
Differentiate between matter and energy and between potential energy and kinetic energy.
Matter:
• Anything that has mass and occupies space.
o Matter can be seen, smelled, and/or felt.
o Weight is mass plus the effects of gravity.
• States of Matter:
o Solid: definite shape and volume
o Liquid: changeable shape; definite volume
o Gas: changeable shape and volume
Energy:
• Energy is the capacity to do work or put matter to into motion.
• Energy does not have mass, nor does it take up space.
• The greater the work done, the more energy it uses up.
o Kinetic energy: energy in action
o Potential energy: stored (inactive) energy
▪ Energy can be transformed from potential to kinetic energy.
▪ Stored energy can be released, resulting in action.
Describe the major energy forms.
Forms of Energy:
• Chemical energy:
o Stored in bonds of chemical substances.
• Electrical energy:
o Results from movement of charged particles.
o Ions: sodium, potassium, calcium
• Mechanical energy:
o Directly involved in moving matter
• Radiant or electromagnetic energy:
o Travels in waves (Ex: heat, visible light, UV light, and X rays)
Energy form conversions
• Energy may be converted from one form to another.
o For example: turning on a lamp converts electrical energy to light energy.
• Energy conversion is inefficient.
o Some energy is “lost” as heat, which can be party unusable energy.
Define chemical elements and list the four elements that form the bulk of body matter.
Chemical Elements:
• Elements are substances that cannot be broken down into simpler substances by ordinary
chemical methods.
o Four elements make up 96% of the body:
1. Carbon (C)
• 18.5%
• Component of all organic moleculues; carbohydrates, lipids, proteins,
and nucleic acids
2. Oxygen (O)
• 65%
• Component of both inorganic (non-carbon containing) and organic
molecules
• Needed for production of cellular energy (ATP)
3. Hydrogen (H)
• 9.5%
• Component of all organic molecules
• Influences pH of body fluids
4. Nitrogen (N)
• 3.2%
• Component of proteins and nucleic acids (genetic material)
o
o
•
9 elements make up 3.9% of the body.
11 elements make up <0.01%
1. Calcium: found as salt in bones and teeth, muscle contraction, blood clotting,
nerve impulses.
2. Phosphorus: part of calcium phosphate in bones and teeth.
3. Potassium: necessary for nerve impulses and muscle contraction.
4. Sulfur: component of proteins; muscle proteins
5. Sodium: major positive ion (cation) found in extracellular fluids. Important for
water balance, nerve conduction, muscle contraction.
6. Chlorine: most abundant negative ion (anion) in extracellular fluids.
7. Magnesium: present in bone.
8. Iodine: needed to make functional thyroid hormones.
9. Iron: component of hemoglobin (which transports oxygen within the red blood
cells).
Periodic table lists all known elements.
Define atoms. List the subatomic particles and describe their relative masses, charges,
and positions in the atom.
Atoms:
• All elements are made up of atoms.
• Unique building blocks from each element.
• Smallest particles of an element with properties of that elements
• What give each element its physical and chemical properties.
Atomic Symbol:
• One- or two- letter chemical shorthand for each element.
o Ex: Carbon = C, Oxygen = O
o Some come from Latin names
• Physical properties:
o Color, texture, boiling point, freezing point
• Chemical properties:
o Bonding, how they behave.
Structure of Atoms:
• Protons:
o Carry a positive (+) charge.
o Weigh an arbitrary of 1 atomic mass unit (1 amu)
• Neutrons:
o Have no electric charge (0)
o Also weigh 1 amu
• Electrons:
o Carry a negative charge (-)
o Are so tiny they have virtually no weight (0 amu).
• Number of positive protons is balances by number of negative electrons, so atoms are electrically
neutral.
• Protons and neutrons are found in a centrally located nucleus; electrons orbit around the nucleus.
o Planetary model (2D)
▪ Simplified and outdates because it incorrectly depicts electrons in orbits, fixed
circular paths.
o
Orbital model (3D)
▪ Current model used to depict orbitals, probably regions where an electron is most
likely to be located (rather than fixed orbits).
Define atomic number, atomic mass, atomic weight, isotope, and radioisotope.
Atomic number:
• Number of protons in nucleus
• Written as subscript to left of atomic symbol.
Mass Number:
• Total number of protons and neutrons in nucleus.
• Total mass of an atom.
• Written as superscript to the left of atomic symbol.
Isotopes:
• Structural variations of same element
• Atoms contain same number of protons but differ in the number of neutrons they contain.
o Atomic numbers are same but mass number are different.
o Ex: Hydrogen with different neutrons.
Radioisotopes:
• Isotopes that decompose to more stable forms
• Atom loses various subatomic particles.
o Sometimes loss results in an isotope becoming a different element.
• An isotope decays, subatomic particles that are being given off release a little energy.
o This energy is referred to as radioactivity.
▪ Alpha, beta, gamma particles.
o Can be detected and measured with scanners.
• Radioisotopes are a valuable tool for biological research and medicine.
o Share same chemistry as their stable isotopes so will be taken up by body.
▪ Can then be used for diagnosis of disease.
o All radioactivity can damage living tissue.
▪ Some types can be used to destroy localized cancers.
▪ Some types cause cancer.
• Radon from uranium decay causes lung cancer.
Define molecules and distinguish between a compound and a mixture.
Molecule:
• General term for 2 or more atoms bonded together.
• H2, O2
Compound:
• Specific molecule that has 2 or more different kinds of atoms bonded together.
• C6H12O6
Compare solutions, colloids, and suspensions.
Mixtures:
• Two or more components that are physically intermixed.
o Solutions:
▪ May be solids liquids, and gases.
▪ Homogenous mixtures, meaning particles are evenly distributed throughout.
▪
▪
•
•
•
Solvent: substances present in greatest amount (liquid, water)
Solute: substance dissolved in solvent, present in smaller amount (glucose,
blood)
▪ True solutions are usually transparent.
▪ Concentration of true solutions:
• Percent of solute in total solution:
o How many parts of solute are in 100 total parts of solution?
o Solvent is usually water.
o 10 parts salt to 90 parts water is a 10% salt solution.
• Milligram per deciliter (mg/dl)
o Deciliter equals 1/100th of a liter.
o Ex: normal fasting blood glucose levels are around 80 mg/dl.
• Molarity (M) is the number of moles of solute per liter of solvent (water)
o 1 mole of a compound is equal to its molecular weight (sum of
atomic weights in grams)
o 1 mole of any substance always contains 6.02x10^23 molecules
of that substance = Avogadro’s number
o Molarities in the body is so small (can be 0.0001 M) they are
expressed in millimoles (mM) so 1000 mM = 1M
o Colloids:
▪ Also known as emulsions; are heterogenous mixtures, meaning that particles are
not evenly distributed throughout mixture.
• Can see large solute particles in solution, but these do not settle out.
• Gives solution a cloudy or milky look.
▪ Some undergo sol-gel (solution to gel) transformations.
• Cytosol of cell is also a sol-gel type solution.
o Suspensions:
▪ Heterogenous mixtures that contain large, visible solutes that do settle out.
▪ Ex: mixture of water and sand
▪ Blood is considered a suspension because if left in a tube, the blood cells will
settle out.
Compounds are only homogenous.
Mixtures can be heterogenous or homogenous.
Mixtures do not have chemical bonding between components.
Explain the role of electrons in chemical bonding and in relation to the octet rule.
Chemical bonds:
• “Energy relationships” between electrons of reacting atoms.
• Electrons are subatomic particles that are involved in all chemical reactions.
o They determine whether a chemical reaction will take place and if so, what type of
chemical bond is formed.
Role of Electrons:
• Electrons can occupy areas around nucleus called electron shells.
• Each shell contains electrons that have a certain amount of kinetic and potential energy, so shells
are also referred to as energy levels.
• Depending on size, an atom can have up to 7 electron shells.
• Shells can hold only a specific number of electrons the shell closest to nucleus is filled first.
o Shell 1 can hold only 2 electrons.
o Sell 2 holds a maximum of 8 electrons.
o Shell 3 holds a maximum of 18 electrons.
•
•
Outermost electron shell is called valence shell.
o Electrons in valence shell have the most potential energy because they are farthest from
the nucleus.
o These are electrons that are involved in chemical reactions.
Octet Rule:
o Atoms desire 8 electrons in their valence shell
▪ Exceptions: smaller atoms (examples: H and He) only want 2 electrons in shell 1
o Desire to have 8 electrons is driving force behind chemical reactions.
▪ Noble gases already have full 8 valence electrons (or 2 for He) so are not
chemically reactive.
o Most atoms do not have full valence shells.
▪ Atoms will gain, lose, or share (form bonds) with other atoms to achieve stability
of 8 electrons in valence shell.
Differentiate among ionic, covalent, and hydrogen bonds.
Ionic bonds:
• Ions are atoms that have gained our lost electrons and become charged.
o Number of protons does not equal number of electrons.
• Ionic bonds involve the transfer of valence shell electrons from one atom to another, resulting in
ions.
o One become an anion (negative charge)
▪ Atom that gained one or more electrons.
o One becomes a cation (positive charge)
▪ Atom that lost one or more electrons
• Attraction of opposite charges results in an ionic bond.
• Ex: NaCl, FCl, KCl
• Most ionic compounds are salts.
Covalent bonds:
• Covalent bonds are formed by sharing of two or more valence shell electrons between two atoms.
o Sharing of 2 electrons results in a single bond.
o Sharing of 4 electrons is a double bond.
o Sharing of 6 electrons is a single bond.
• Allows each atom to fill its valence shell at least part of the time.
• Two types of covalent bonds:
1. Polar: unequally
2. Nonpolar: equally
Hydrogen bonds:
• Attractive force between electropositive hydrogen of one molecule and an electronegative atom
of another molecule.
o Not true bond, more of a weak magnetic attraction.
• Common between dipoles such as water
• Hydrogen bonds are attracted to a more electronegative molecule.
Compare and contrast polar and nonpolar compounds.
Polar:
• Unequal sharing of electrons
• Results in electrically polar molecules
• H2O
• Creates dipole (unequal charges)
Nonpolar:
• Equal sharing of electrons
• Results in electrically balanced, nonpolar molecules
• CO2
Polar & Nonpolar similarities:
• Bother are types of covalent bonds
Define the three major types of chemical reactions: synthesis, decomposition, and exchange.
Comment on the nature of oxidation-reduction reactions and their importance.
• Compounds are represented as molecular formulas
• Subscript indicates atoms joined by bonds.
• Prefix denotes number of unjoined atoms or molecules.
• Subscripts indicates how many atoms are joined by bonds, whereas prefix means the
unjoined bonds.
3 main types of chemical reactions:
1. Synthesis:
a. (combination) reactions involve atoms or molecules combining to form larger more
complex molecule.
b. Used in anabolic (building) processes.
i. A + B → AB
ii. Amino acids to proteins
2. Decomposition:
a. Reactions that involve the breakdown of a molecule into smaller molecules or its
constituent atoms (reverse of synthesis reactions).
b. Involve catabolic (bond-breaking) reactions.
i. AB → A + B
ii. Glycogen to glucose
3. Exchange:
a. Reactions also called displacement reaction, involve both synthesis and decomposition.
b. Bonds are both made and broken.
i. AB + C → AC + B
ii. AB + CD → AD + CB
Reduction-oxidation or redox reactions:
• Exchange reactions in living systems, atoms are reduced when they gain electrons and oxidized
when they lose electrons.
• Ex: C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP
o Glucose is oxidized and oxygen molecule is reduced
• OIL: oxidation is losing
• RIG: reduction is gaining
Explain why chemical reactions in the body are often irreversible.
Although all chemical reactions are reversible, many biological reactions are not. This is due to the
energy requirements to go backward being too high, or products have been removed.
Describe factors that affect chemical reaction rates.
Affecting Factors:
1. Temperature
a. Increased temperatures usually increase rate of reaction.
2. Concentration of reactants:
a. Increased concentration usually increase rate of reaction.
3. Particle size
a. Smaller particles usually increase rate of reaction.
•
Catalysts increase the rate of reaction without being chemically changed or becoming a part of
the product.
o Enzymes are biological catalysts; speed up rate of reactions and/or breakdowns.
Explain the importance of water and salts to body homeostasis.
Water:
• Water is an important inorganic compound because of its properties (High heat capacity, high
heat vaporization, polar solvent properties, reactivity, cushioning)
• Accounts for 60%-80% of the volume of living cells
• Properties
o High Heat Capacity: ability to absorb and release heat with little temp change and
prevents sudden changes in temp.
o High Heat of Vaporization Evaporation requires large amounts of heat, and it is a
useful cooling mechanism.
o Polar Solvent Properties: dissolves and dissociates ionic substances additionally
forming hydration (water) layers around large, charged molecules.
▪ Example: Proteins; body's major transport.
o Reactivity: necessary part of hydrolysis and dehydration synthesis reactions
o Cushioning: protects certain organs from physical trauma.
▪ Example: Cerebrospinal fluid cushions nervous system organs.
Salts (ionic compounds):
• Play role in body functions (sodium, potassium, calcium, and iron).
• Ionic Balance is vital for homeostasis. In body (NaCl, CaCO3,KCl, calcium phosphates)
• Separate into cations and anions.
o Ions called electrolytes because they can conduct electrical currents in solution.
Define acid and base and explain the concept of pH. (slide 83-84)
• Acids and Bases are Both Electrolytes.
Acid:
• Proton Donors, Releases Hydrogen Ions
o HCl → H(+) + Cl(-)
o HCl, HC2H3O2
Base:
• Proton acceptors, pick up H+ ions.
o NaOH → Na(+) + OH(-)
o When a base dissolves in a solution, it releases a hydroxyl ion.
o Bicarbonate (HCO3(-)) and ammonia NH3
pH: Acid-base concentration
• pH scale is a measurement of concentration of hydrogen ions [H+] in a solution.
•
•
The more hydrogen ions in a solution, the more acidic
pH scale = 0-14 ; logarithmic so each pH unit represents a 10-fold difference
o Acidic solutions have a high [H+] but low pH
▪ Range is 0-6.99
o Neutral solutions have equal number of [H+] and OH- ions
▪ All neutral solutions are pH 7
• Water, blood
o Alkaline (basic) solutions have low [H+] but high pH
▪ Alkaline pH range is 7.01-14
Neutralization reaction: acids and bases are mixed together.
• Displacement reaction occurs, forming a water and salt.
o NaOH + HCl → NaCl + H2O
Buffers: acidity resist abrupt hydrogen ions and large swings in pH
• Can release hydrogen ions if pH rises
• Can bind hydrogen ions if pH falls
• Convert strong acids or bases into weak ones
o Ex: Carbonic acid-bicarbonate system (buffer for blood)
Explain the role of dehydration synthesis and hydrolysis in forming and breaking down
organic molecules.
• The major molecules (carbohydrates, lipids, proteins, and nucleic acids) are polymers
(bigger molecules).
• Polymers are made up of monomers (building blocks)
• Organic compounds (polymers) are synthesized by dehydration synthesis.
• Organic compounds (polymers) are broken down by hydrolysis reactions.
Describe and compare the building blocks, general structures, and biological functions
of carbohydrates.
• Glucose + Fructose = Sucrose
• Glucose + Glucose = Maltose
• Glucose + Galactose = Lactose
Carbohydrates: include sugar and starches
• Contain C, H, and O
• Three classes:
o Monosaccharides: one single sugar
▪ Monomer is smallest unit of carbohydrate.
▪ Glucose = hexose sugar
▪ Fructose
▪ Galactose
▪ Deoxyribose = pentose sugar
▪ Ribose = pentose sugar
o Disaccharides: two sugars
▪ Too large to pass through cell membranes.
▪ Formed by dehydration synthesis 2 monosaccharides
▪ Sucrose
▪ Maltose
▪ Lactose
o
Polysaccharides: many sugars
▪ Polymers are made up of monomers and monosaccharides.
▪ Glycogen: carb storage form used by animals
▪ Starch: carb storage form used by plants
▪ Not very soluble
Describe the building blocks, general structures, and biological functions of lipids.
Lipids:
• Contain C, H, O, but less than carbohydrates.
• Insoluble in water
• 4 main types:
1. Triglycerides
a. Called fats when solid and oils when liquid.
b. Composed of 3 fatty acids (linear hydrocarbons) bonded to a glycerol molecule
(sugar alcohol) by dehydration synthesis.
c. Function: energy storage, insulation, and protection.
d. Constructed of saturated fatty acids
i. Saturated: NO DOUBLE BONDS; solid form animals fats, butter, etc.
ii. Unsaturated: DOUBLE BONDS
1. Trans fats: resemble unhealthy saturated fats.
2. Omega-3 fatty acids: heart healthy; olive oil
2. Phospholipids:
a. Modified triglycerides
b. Important for cell membrane
c. Head and tail regions have different properties.
i. Head is polar and hydrophilic.
ii. Tail is nonpolar and hydrophobic.
3. Steroids:
a. Consist of four interlocking ring structures
b. Most important steroid is cholesterol.
i. Made by liver and also found in animal products (ex: cheese, eggs, etc.)
c. Starting material for Vitamin D synthesis, steroid hormones and bile salts
d. Important in cell plasma membrane structure
4. Eicosanoids:
a. Derived from a fatty acid (arachidonic acid) found in cell membranes
b. Most important are prostaglandins
i. Play a role in blood clotting, control of blood pressure, inflammation,
and labor contractions.
ii. Inflammatory actions are blocked by NSAIDs (non-steroidal antiinflammatory drugs, such as aspirin and ibuprofen)
Describe the four levels of protein structure.
1. Primary: Linear sequence of Amino Acids (Forms the polypeptide chain) Order of AA
2. Secondary: How primary Amino Acids interact with each other (form spirals/helices and sheets)
a. Alpha Helix: resemble a spring primary chain coiled to form a spiral structure which is
stabilized by hydrogen bonds.
b. Beta pleated sheets: resemble accordion ribbons, held together by hydrogen bonds
3. Tertiary: How secondary structures interact
4. Quaternary: how 2 or more different polypeptides interact with each other
Describe enzyme action.
Enzymes:
• Lower activation energy
o Substrate binds to enzyme active site, temporarily forming enzyme substrate complex
o Complex undergoes rearrangement of substrate, resulting in final product
o Product is released from enzyme
• Enzymes are specific
o Act on very specific substrate
• Names usually end in -ase (ex: hydrolase, oxidase)
• Most functional enzymes are holoenzymes, consisting of:
o Apoenzyme: (protein portion)
o Cofactor: (metal ion) or coenzyme (organic molecule, often a vitamin)
Compare and contrast DNA and RNA.
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DNA & RNA are both nucleic acids.
DNA holds genetic blueprint for synthesis of all proteins, double stranded helix located in cell
nucleus (follows complementary base-pairing rules) A always pairs T G always pairs C.
o Purines: Adenine (A) and Guanine (G)
o Pyrimidines: Thymine (T) and Cytosine (C)
RNA active outside nucleus, single stranded, So A pairs with U G pairs with C.
o Contains a ribose sugar (not a deoxyribose)
o Thymine replaced with Uracil
o Three varieties of RNA carry out the DNA orders for protein synthesis:
▪ Messenger RNA; mRNA (transcription)
▪ Transfer RNA; tRNA
▪
Ribosomal RNA; rRNA
Explain the role of ATP in cell metabolism.
Chemical energy released when glucose is broken down is captured in ATP (Adenosine triphosphate)
• ATP directly power chemical reaction in the cells.
o Offers immediate, usable energy needed by body cells.
• Structure of ATP
o Adenine-containing RNA nucleotide with two additional phosphate group
Additional:
Inorganic compounds: non-carbon based
• Water
• Salts
• Acid and bases
Organic compounds: carbon based
• Carbohydrates
• Fats
• Proteins
• Nucleic acids
Chapter 3
List the three major regions of a generalized cell and their functions.
1. Plasma Membrane:
a. Flexible outer boundary
b. Acts as an active barrier separating intracellular fluid from extracellular fluid it plays a
dynamic role in cellular activity by controlling what enters and what leaves the cell.(cell
Membrane)
2. Cytoplasm:
a. Intracellular fluid containing organelles.
3. Nucleus:
a. DNA containing control center
Compare the structure and function of tight junctions, desmosomes, and gap junctions.
Some cells are free (not bound to any other cells); Ex: blood, sperm
3 ways cells can be bound to one another:
1. Tight Junctions:
a. Integral proteins on adjacent cells fuse to form an impermeable junctions that encircles
whole cell.
b. Prevents fluids and most molecules from moving in between cells.
c. In the skin, they keep us somewhat watertight and help keep allergens out of our body. In
the digestive system, they help prevent the leakage of digestive enzymes into our
bloodstream.
2. Desmosomes:
a. Rivet-like cell junction formed when linker proteins (cadherins) of neighboring cells
interlock like the teeth of a zipper.
b. Linker protein is anchored to its cell through thickened “button-like” areas on inside of
plasma membrane called plaques.
c. Keratin filaments connect plaques intercellularly for added anchoring strength.
d. Desmosomes allow “give” between cells, reducing the possibility of tearing under
tension.
3. Gap junctions:
a. Transmembrane proteins (connexons) form tunnels that allow small molecules to pass
from cell to cell.
b. Used to spread ions, simple sugars, or other small molecules between cells
c. Allows electrical signals to be passed quickly from one cell to the next cell
i. Used in cardiac and smooth muscle cells.
Relate plasma membrane structure to active and passive transport processes.
Plasma Membrane:
• acts as an active barrier between intracellular fluid and extracellular fluid.
• Consists of membrane lipids that form flexible lipid bilayer.
o Lipid Bilayer made up of 75% phospholipids, 5% glycolipids, 20% cholesterol
• Surface sugars form glycocalyx
• Selectively permeable allowing only certain molecules to cross.
o Passive transport: no energy is required.
o Active transport: energy (ATP) is required.
Passive transport: Requires no energy input.
• HIGH TO LOW CONCENTRATION
• Three types of passive transport:
o Simple diffusion:
▪ Direct diffusion:
o Facilitated diffusion: get help.
o Osmosis: use aquaporins via faciliated diffusion.
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•
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•
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All types involve diffusion – natural movement of molecules from areas of high concentration to
areas of low concentration.
o Also referred to as moving down a concentration gradient.
All molecules have random, high-speed movement due to their intrinsic kinetic energy.
Movement results in collisions between molecules.
Molecules in higher concentrations areas collide more resulting in molecules being scattered to
lower concentrations.
Lipid soluble go through the phospholipid cell membrane easiest. Easier than water because
the cell membrane is 75% of membrane is phospholipids.
Active transport: requires energy (ATP) to move across plasma membrane.
• Due to solute being too large for channels, no lipid soluble, or move down the concentration
gradient.
• LOW TO HIGH CONCENTRATION (against concentration gradient)
• Two major types:
o Active transport
o Vesicular transport: involves transport of large particles, macromolecules, and fluids
across membrane in membranous sacs called vesilcles
• Require carrier proteins:
o Antiporters – transport one substance into cell and one substance out of the cell
o Symporters – transport two different substances in the same direction
• Two types of active transport:
1. Primary active transport:
a. Required energy comes directly from ATP hydrolysis
i. Sodium-Potassium pump: pumps sodium out of the cell and potassium
back into the cell. (active in the nerves and muscles)
2. Secondary active transport
a. Required energy is obtained indirectly from ionic gradients created by primary
active transport
i. Sodium can drag other molecules with it as it flows into cell through
carrier proteins (usually symporters) in membrane. Some sugars, amino
acids, and ions are usually transported into cells via secondary active
transport.
ii. Driven by the concentration gradient created by primary transport.
Compare and contrast simple diffusion, facilitated diffusion, and osmosis relative to
substances transported, direction, and mechanism.
Speed of diffusion influenced by 3 factors:
• Concentration
o The greater the difference of concentration between two areas, the faster diffusion occur.
• Molecular Size
o Smaller molecules diffuse faster.
• Temperature
o Higher temps increase kinetic energy which results in faster diffusion.
Equilibrium is reached when there is no net movement of molecules in one direction only.
Simple diffusion:
• Molecules that can passively diffuse through membrane via phospholipid bilayer include:
o Lipid-soluble and nonpolar substances
o Very small molecules that can pass through membrane or membrane channels
▪ Ex: oxygen, carbon dioxide, steroid hormones, fatty acids
Facilitated diffusion:
• Larger or non-lipid soluble or polar molecules can cross membrane but only with assistance of
carrier molecules.
• Go down their concentration gradient
o Ex: glucose, amino acids, ions
• Carrier-mediated facilitated diffusion
o Substances bind to carrier proteins.
• Channel-mediated facilitated diffusion
o Substances move through water-filled channels (aquaporins)
o Leakage channels: always open
o Gated channels: controlled by chemical or electrical signals.
Osmosis:
• Movement of solvent (usually water), not molecules.
•
Tonicity: ability of a solution to change the shape or tone of cells by altering the cells’
internal water volume
o Isotonic solution: same osmolarity as inside the cell, so volume remains unchanged.
o Hypertonic solution: has higher osmolarity then inside cell, so water flows out of cell,
resulting in cell shrinking (crenation).
o Hypotonic solution: has lower osmolarity than inside cell, so water flows into cell,
resulting in cell swelling; cells can lead to bursting (lysing).
Compare and contrast endocytosis and exocytosis in terms of function and direction.
Endocytosis: transport into cell
• 3 different types of endocytosis: phagocytosis, pinocytosis, receptor-mediated endocytosis
• Involves formation of protein coated vesicles
• Some pathogens are capable of hijacking receptor for transport into cell
Exocytosis: transport out of the cell
• Transcytosis: transport into, across, and the out of the cell
• Vesicular: transport from one area or organelle in cell to another
Compare and contrast pinocytosis, phagocytosis, and receptor-mediated endocytosis.
Phagocytosis:
• Type of endocytosis that is referred to as “cell-eating”
• Cell engulfs a large particle by forming a projecting pseudopod
• Formed vesicle is called a phagosome.
• Phagocytosis is used by macrophages and certain other white blood cells
Pinocytosis:
• Type of endocytosis that is referred to as “cell drinking” or fluid-phase endocytosis
• Fuses endosome
• The cell “gulps” a drop of extracellular fluid containing solutes into tiny vesicles.
Receptor-mediated endocytosis:
• Involves endocytosis and transcytosis of specific molecules.
• Extracellular substances bind to a specific receptor protein, enabling the cell to ingest and
concentrate specific substances in protein-coated vesicles.
Discuss the structure and function of mitochondria.
Mitochondria:
• “Power plant/house” of the cells because they produce most of cells energy molecules (ATP) via
aerobic (oxygen-requiring) cellular respiration.
• Enclose by double membranes; inner membrane has many folds, called cristae (play a role in
cellular respiration)
Discuss the structure and function of ribosomes, the endoplasmic reticulum, and the Golgi
apparatus, including functional interrelationships among these organelles.
Ribosomes: site of protein synthesis
• Free ribosomes: free floating; site of synthesis of soluble proteins that function in cytosol or
other organelles
• Membrane ribosomes: attached to membrane of endoplasmic reticulum (ER); site of synthesis
of proteins to be incorporated into membranes or lysosomes.
Endoplasmic Reticulum: consists of series of parallel, interconnected cisterns – flattened membranous
tubes that enclose fluid-filled interiors. Continuous with outer nuclear membrane.
• Two varieties:
1. Rough ER:
a. External surface appears to be rough because it is studded with ribosomes.
b. Site of synthesis of proteins that will be secreted from the cell
c. Site of synthesis of many plasma membrane proteins and phosopholipids
d. Sends to golgi apparatus for further processing
2. Smooth ER
a. Network of looped tubles continuous with rough ER
b. Lipid metabolism
c. Absorption, synthesis and transport of fats
d. Detoxification of certain chemicals (drugs, pesticides)
e. Converting of glycogen to free glucose
f. Storage and release of calcium
Golgi Apparatus: stacked and flattened membranous cistern sacs
• Package, transport, and modify what the rough ER and smooth ER make [FedEx]
Compare the functions of lysosomes and peroxisomes.
Lysosomes:
• Spherical bags containing digestive enzymes
• Digest ingested bacteria, viruses and toxins
• Break down and release glycogen.
• Causes autolysis; intracellular release in injured causes cells to digest themselves
Peroxisomes:
• Membranous sacs containing powerful detoxifying substances that neutralize toxins
• Role in breakdown and synthesis of fatty acids.
Name and describe the structure and function of cytoskeletal elements.
Cytoskeleton: acts as cells “bones, ligaments, and muscle” by playing in movement of cell
component.
• Motor proteins help with movement of organelles and other substances around cell and
powered by ATP.
• Three types:
1. Microfilaments
a. Thinnest of all cytoskeletal elements
b. Strands made of spherical protein subunits called actin.
2. Intermediate filaments
a. Size in between microfilaments and microtubules
b. Tough, insoluble, rope-like protein fibers constructed like woven ropes
composed of tetramer fibrils.
3. Microtubules
a. Largest of cytoskeletal elements; consist of hollow tubes composed of protein
subunits called tubulins, which are constantly being assembles and disassembles
b. Most radiate from centrosome are of cell.
List the phases of the cell cycle and describe the key events of each phase.
1. Interphase: cell grows and carries on its usual activities
a. Consist of subphases: which include the process of DNA replication
i. GS1 (gap 1): vigorous growth and metabolism
ii. S (synthetic): DNA replication occurs
iii. GS2 (gap 2): preparation for division
b. Prior to division, the cell makes a copy of the DNA
c. Double stranded DNA helices unwind and unzip
i. Replication fork: point where strand separates
ii. Replication bubble: active area of replication
2. Cell Division (mitotic phase): cell divides in two
a. Early Prophase
b. Late Prophase
c. Metaphase
d. Anaphase
e. Telophase
f. Cytokenisis
A segment of DNA that holds the code for one polypeptide is referred to as a gene.
Genes are composed of exons and introns
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– Exons are part of gene that actually codes for amino acids
– Introns are noncoding segments interspersed amongst exons
Name the two phases of protein synthesis and describe the roles of DNA, mRNA,
tRNA, and rRNA in each phase.
1. Transcription
a. DNA information coded in mRNA.
b.
2. Translation
a. mRNA decoded to assemble polypeptides.
Contrast triplets, codons, and anticodons.
Triplets: Three-base sequence on DNA
Codons: Three-base sequence on mRNA
Anticodons: Three-base sequence which binds to the mRNA codon calling for amino acid carried by
tRNA.