Name______________________
Human Physiology
Exam #1 (Ch.1-10)
Fall 2011
Mark each true or correct statement with a T and each false or incorrect statement with an F. (70)
_______1.
Homeostasis is the maintenance of nearly constant conditions in the internal environment.
_______2.
The Central Nervous System operates at a subconscious level and controls many
functions of the internal organs.
_______3.
Adaptive control is used to correct or alter feed-forward mechanisms of control systems.
_______4.
Fibrillar proteins found in collagen and elastic fibers of connective tissue and in blood
vessel walls are examples of functional proteins.
_______5.
The hydrophilic phosphate portions of a membrane constitute the two surfaces (outer and
inner) of the complete membrane.
_______6.
Integral proteins can function as carrier or channel proteins in the cell membrane.
_______7.
Phospholipids and cholesterol are synthesized by the Golgi complex.
_______8.
The most important initiator of amoeboid movement is chemotaxis.
_______9.
The genetic code is unambiguous in that each amino acid has only one codon.
_______10.
Activation of RNA nucleotides is accomplished by the enzyme, RNA polymerase.
_______11.
Single stranded RNA that regulates gene transcription and translation is called
microRNA.
_______12.
Regulation of gene expression provides organisms with the ability to respond to changes
in the environment.
_______13.
The last step of cell reproduction is replication of DNA.
_______14.
Because of repair and proof-reading transcription processes rarely make a mistake.
_______15.
The lipid bilayer is not miscible with either the extracellular or intracellular fluids.
_______16.
Facilitated diffusion requires the interaction of a carrier protein while simple diffusion
relies on the kinetic movement of molecules.
_______17.
Electrical charges on ions cause them to move through a membrane even though no
concentration gradient may exist.
_______18.
The membrane is more permeable to sodium ions so once they are on the outside of the
membrane, they have a tendency to stay there.
_______19.
The concentration of sodium ions, potassium ions, and the sodium-potassium pump all
contribute to the negativity of the resting membrane potential.
_______20.
The membranes of almost all cells of the body have a calcium pump similar to that of the
sodium pump.
_______21.
A triad is made up of a transverse tubule and two terminal cisternae of the sarcoplasmic
reticulum.
_______22.
When contraction of skeletal muscle occurs, the A band decreases in length.
_______23.
The amount of actin and myosin overlap determines the tension developed by the
contracting muscle.
_______24.
The first source of energy to replace the ATP used in muscle contraction comes from
oxidative metabolism (i.e. cellular respiration).
_______25.
In smooth muscle the actin filaments are attached to dense bodies and the myosin
filaments are interspersed among the actins.
_______26.
Acetylcholine may act as either an excitatory neurotransmitter or inhibitory
neurotransmitter depending on the organ in question.
_______27.
In smooth muscel the action potential is caused mainly by calcium, not sodium.
_______28.
Heart beating at a very fast rate does not allow complete filling of the heart chambers
before the next contracton starts.
_______29.
The AV valves prevent backflow of blood from the pulmonary trunk or aorta to the
ventricles during systole.
_______30.
Afterload is the pressure in the aorta leading from the ventricle.
_______31.
Within physiological limits the heart pumps all the blood that returns to it by the way of
the veins.
_______32.
The AV bundle (His) allows two way conduction of the action potential which allows the
impulse to travel more quickly over the ventricles.
_______33.
An ectopic pacemaker occurs when the AV node or AV bundle acts as the initiator of the
action potential instead of the SA node.
_______34.
Acetylcholine is the main neurotransmitter released by the parasympathetic nerves in the
heart.
_______35.
Only about 10% of the blood flows from the atria into the ventricles before the atria
contract.
Select the one best answer that either defines or completes the meaning of the given statement. (60)
_______1.
Energy from ATP is used for
A.
B.
C.
D.
Transport of substances through multiple membranes
Synthesis of chemical compounds
Mechanical work
All of the above are correct
_______2.
Secretory vesicles and lysosomes are formed by the
A.
B.
C.
D.
_______3.
The control center of the cell is the
A.
B.
C.
D.
_______ 4.
Kidneys
Liver
Lungs
All of the above are correct
An example of positive feedback is
A.
B.
C.
D.
_______8.
Nervous
Immune
Endocrine
Reproductive
The removal of metabolic end products is accomplished by
A.
B.
C.
D.
_______7.
Lysosomes
Golgi apparatus
Peroxisomes
Mitochondria
Which of the following systems is least involved in homeostatic mechanisms and/or the
regulation of body functions?
A.
B.
C.
D.
_______6.
Nucleolus
Nucleus
Mitochondria
Centrioles and centrosomes
Self-replicating organelle that contains oxidase enzymes rather than hydrolase enzymes
A.
B.
C.
D.
_______5.
Golgi apparatus
Smooth endoplasmic reticulum
Rough endoplasmic reticulum
Mitochondria
Regulation of blood sugar levels
Regulation of body temperature
Blood clotting mechanism
Regulation of blood pressure
Place the following mitotic events in order
1.
2.
3.
4.
A.
B.
C.
D.
metaphase
prophase
telophase
anaphase
2,1,4,3
1,2,4,3
1,3,2,4
1,2,3,4
_______9.
Why do cancer cells kill?
A.
B.
C.
D.
_______10.
In DNA replication
A.
B.
C.
D.
_______11.
B.
C.
D.
The sodium potassium pump has three binding sites for potassium
The sodium potassium pump has two binding sites for sodium
One of the most important functions of the Na-K pump is to control cell volume
All of the above are correct
The plateau in some action potentials
A.
B.
C.
D.
_______15.
The rate of diffusion does not reach a maximum rate
Requires input of ATP
Glucose and most amino acids are transport via facilitated diffusion
All of the above are correct
In the active transport of substances through the membrane
A.
B.
C.
D.
_______14.
If a substance is lipid soluble, the rate of diffusion is directly proportional to the
concentration difference on both sides of the membrane
Aquaporins permit the rapid passage of water through cell membranes
Many of the membrane channels are gated
Selective permeability of protein channels are due to characteristics of the
channel itself
In facilitated diffusion
A.
B.
C.
D.
_______13.
Leading strand replicates via Okazaki fragments
Replication proceeds from “top” to “bottom” in both strands
Lagging strand adds nucleotides one at a time and in sequence
The “new” DNA contains both old and new strands.
All of the following are correct concerning diffusion except
A.
_______12.
Grow over and smother normal cells
Use up all of the available nutrients
Produce large amounts of wastes that kill the normal cells
None of the above are correct
Is caused by the rapid repolarization of the membrane immediately after
depolarization
Utilizes two major channels: fast sodium and fast voltage activated calcium
channels
Is characteristically found in cardiac but not skeletal muscle
None of the above are correct
All of the following are true concerning the conduction of a nerve impulse except
A.
B.
C.
D.
APs occur only at the nodes of Ranvier in nnmyelinated axons
Saltatory conduction occurs with myelinated axons
Continuous conduction is faster than salutatory conduction
All of the above are correct
_______16.
Which of the following is incorrect concerning the structure of the sarcomere?
A.
B.
C.
D.
_______17.
Slow, Type I or oxidative fibers
A.
B.
C.
D.
_______18.
C.
D.
There is a slow cycling of the myosin cross bridges
There is a lower energy requirement for smooth muscle versus skeletal muscle
Calcium ions combine with calmodulin
All of the above are correct
Smooth muscle contraction without APs is characterized by all of the following except
A.
B.
C.
D.
_______21.
All of the muscle fibers innervated by a single nerve fiber are called a motor unit
Summation can be caused by motor unit recruitment or increased frequency of
contraction
Increasing the strength of contraction in a stepwise manner is called tetanization
Muscle fatigue increases in almost direct proportion to the depletion of muscle
glycogen
In smooth muscle contraction
A.
B.
C.
D.
_______20.
Have increased numbers of mitochondria
Have the lowest amount of myoglobin
Contain all of the glycolytic enzymes
Are the largest of the muscle fibers
Which of the following is not correct concerning muscle contraction?
A.
B.
_______19.
I bands contain mainly actin filaments and only a few myosin filaments
A sarcomere is defined by the distance between two Z disks.
The springy filaments that help stabilize the myosin filaments are titin
The area that only contains myosin filaments is the H zone
Excess carbon dioxide causes vasodilation
Lack of oxygen causes vasoconstriction
Increased hydrogen ions causes vasodilation
Most hormones cause vasoconstriction
All of the following are true concerning APs in the heart except
A. Slower calcium channels are slow to open and remain open for longer periods of
time
B. The permeability of the cardiac muscle membrane is increases about 5 fold for
potassium
C. Cardiac muscle is refractive to restimulation during an action potential
D. The fast sodium channels are the same for cardiac and skeletal muscle
_______22.
The Frank Starling mechanism of the heart
A. The ability of stretched muscle to contract with increased work output is
characteristic of cardiac muscle
B. Amount of blood pumped by the heart is determined by arterial flow and pressure
C. Can be shown by atrial output or function curves
D. All of the above are correct
_______23.
All of the following are correct except
A. Excess potassium in the extracellular fluid causes the heart to become flaccid and
dilated
B. Excess calcium causes the heart rate to decrease and the heart to become flaccid
C. Fever causes an increase in heart rate
D. Contractile strength of the heart can be enhanced by a moderate temperature increase
_______24.
The P wave of an ECG (EKG) represents
A.
B.
C.
D.
_______25.
Depolarization of the ventricles
Repolarization of the atria
Repolarization of the ventricles
Depolarization of the atria
Concerning the function of the heart valves
A. Chordae tindenae of the AV valves help the valves to close once the atria have
contracted
B. Chordate tindenae are attached to the trabeculae carnae muscles of the ventricles
C. Velocity of blood ejection through the semilunar valves is much greater than that of
the AV valves
D. The heavier AV valves require rapid backflow of blood to close
_______26.
In the autorhythmicity of the heart
A. Discharge rate of the AV node is faster than the self-excitatory discharge rate of the
AV node
B. The AV node controls the beat of the heart
C. An ectopic pacemaker causes an abnormalsequence of contraction
D. All of the above are correct
_______27.
In the conduction of an impulse through the heart
A. Rapid transmission of nerve impulses by Purkinje fibers is due to intercalated disks
B. Under normal conditions the AP can travel from the ventricle to the atria and vice
versa
C. Slow conduction occurs with an increase in the gap junction number
D. All of the above are correct
_______28.
Which of the following is not included in a Wigger diagram?
A.
B.
C.
D.
_______29.
Ventricular volume and pressure
Electrocardiogram
Aortic pressure
Atrial volume and pressure
Which of the following voltages most closely approximates the resting membrane
potential of the heart?
A.
B.
C.
D.
0 mV
120 mV
-20 mV
-80 mV
_______30.
In the excitation-coupling of cardiac muscle
A.
B.
C.
D.
The only source of calcium is from the sarcoplasmic reticulum
Unlike skeletal muscle, there are no transverse tubules in cardiac muscle
Muscle contraction continues as long as high concentrations of calcium are present
All of the above are correct
Choose three of the following essay questions. You may do the fourth as a bonus. (30)




Compare and contrast the excitation-coupling contraction of skeletal vs. cardiac muscle.
Discuss the molecular mechanism of muscle contraction. Include a discussion of the sliding
filament mechanism.
Discuss completely the cardiac cycle; include a pressure-volume diagram.
Discuss the generation and propagation of the action potential.