Biology II Introduction
Scientific Method
Steps of the Scientific Method
1. Observation
2. Hypothesis
3. Experimental Design/Data Collection (Testing the
Hypothesis)
4. Analysis (Explaining the Data)
Important Scientific Method Terms
-Control  Factor in an experiment that stays the same throughout the
course of the experiment. All good experiments have at least one control
-Variable  Factor in the experiment changes. The fewer the variables in
an experiment, the better the design.
-Theory  Hypothesis that is tested repeatedly and never disproved
Anatomy & Physiology Introduction
Anatomy – study of anatomical features or structures
Physiology- study of biological functions
Anatomy & Physiology are linked because form follows
function
Example:
HeartVentricles of heart consist of fibrous muscle
These muscles are used expel blood from the heart to the rest of
the body
TeethMolars are flattened; used for grinding food
Canines & incisors are sharp; used for tearing and cutting food
Teeth
Levels of Structure and Organization in the Body
Level
Example
Atom
Hydrogen, Chlorine
Molecule
Water, Glucose
Macromolecule
DNA, Protein
Organelle
Ribosomes, Nucleus
Cell
Neuron, Muscle cell
Tissue
Connective Tissue
Organ
Skin, Liver
Organ System
Digestive System
Organism
Human, Narwhale
Properties Of Life
1. Made of cells
2. Reproduction
3. Universal genetic code
4. Growth and development
Growth- Increase in Amount of material in an organism
Development- Series of changes an organism undergoes in
becoming an adult
5. Obtain & use energy (from food or sun)
6. Respond to their environment
Stimulus: anything in an organism’s environment that
causes it to react
7. Homeostasis: Organisms maintain constant internal
conditions regardless of external changes
Examples?
8. Evolve: Species change over time
Requirements for Organisms
Water- used for metabolic processes; transport of molecules, regulation
of body temperature
Food- provide nutrients and energy; raw materials for building new
molecules
Oxygen- Used to release energy from nutrients; drives metabolism
Heat- Increases the rate of chemical reactions in the body
Pressure- application of a force on an object; aids in breathing
(atmospheric pressure) and transport (blood pressure)
Homeostasis and Feedback Loops
The stabilization of internal conditions is governed
by 3 components
-Receptors = cells or parts of cells that provide
information about the body’s internal environment
-Control Center = usually Brain of CNS. Tells the
body what the internal environment should be
-Effectors = muscles or glands that alter the
conditions of the internal environment
Negative Feedback Loop
Receptors measure a deviation from the norm, control center registers
the deviation, and effectors return the condition to normal.
Example: Body temperature, blood pressure & blood glucose (book page
12)
Organization of the Human Body
Axial Portion Head and Trunk
Appendicular Portion  Arms and Legs
Body Cavities
Dorsal Cavity  Cranial and Vertebral Cavities
Ventral Cavity  Abdomen, Thoracic, and Pelvic Cavities
Cavity Membranes
Serous Membranes  Line each cavity and hold organs in place
Examples:
Pleural Membranes  Line the Lungs
Pericardial Membrane Lines the Heart
Peritoneal Membrane  Lines the Abdominal cavity
Directional Terms
Superior toward the head or upper part of the body
Example: The heart is superior to the liver
Inferior Away from the head, toward the lower part of the body
Example: The stomach is inferior to the lungs
Anterior  toward the front of the body; a body lying in the prone position
has its anterior side down. In the supine position it is anterior
side is up
Example  The sternum is anterior to the heart
Posterior  Toward the back of the body
Example: The esophagus is posterior to the trachea
Medial  Nearer to the midline of the body. The midline is an imaginary
vertical line that divides the body into left and right halves
Example: The heart is medial to the scapula
Lateral  Farther from the midline of the body
Example: The lungs are lateral to the heart
Intermediate  Between 2 structures
Example: Your middle finger is intermediate to your index and ring
finger
Directional Terms
Ipsilateral  On the same side of the body
Example: The appendix and small intestine are ipsilateral
Contralateral  On the opposite sides of the body
Example: The large intestine and small intestine are contralateral
Proximal  Nearer to the trunk of the body; nearer
Example: The humerus is proximal to the radius
Distal Farther from the trunk of the body; farther away
Example: The phalanges are distal to the carpals (wrist bones)
Superficial  Toward the surface of the body
Example: The sternum is superficial to the heart
Visceral  Toward the inside of the body
Example: The ribs are visceral to the skin
Parietal  Forming the outer wall of a body cavity
Example  The parietal pleura from the external surface of the
lungs
Divisions of the Body
Sagittal Plane  Vertically divides the body into 2 parts;
left and right
Frontal PlaneDivides the body into 2 parts; anterior and
posterior
Transverse Plane  Divides the body from top to bottom;
superior (cranial) to inferior (caudal)
Anatomy & Physiology Subdivisions
•Gross Anatomy  Study of structures that can be seen without a
microscope
•Systemic Anatomy  Study of specific systems
•Radiographic Anatomy  Study of structures using X-rays
•Developmental Anatomy  Study of zygotes to adults
•Embryology  Study of zygote to 8th week in utero
•Histology  Study of tissues
•Cytology  Study of cells
•Pathological Anatomy  Study of structural changes associated
with disease
•Pathophysiology  Study of functional changes associated with
disease
•Neurophysiology  Study of the function of nerve cells
•Endocrinology  Study of hormone function
•Immunology  Study of body’s defenses
•Renal Physiology  Study of kidney function