kin 270 final practice exam

Which of the following processes releases energy?

Allowing two different areas to become more similar

The inside of a cell contains several buffers. These buffers help ensure that

pH inside the cell remains stable when extracellular pH changes

A muscle fiber that fires a single action potential but never repolarizes will

Generate force for a short period of time and relax (a twitch)

Many choice: Which of the following is a dense connective tissue?

The reticular layer of the dermis

Tendon

If a red blood cell is placed in a very dilute solution, what will happen

The cell will burst

Assume that the temperature outside is 20 degrees C (68 F) and you have a bucket of water that is also 20 degrees C. The humidity is very low so water evaporates quickly. If a person takes a dry hand and sticks it into the water, would thermoreceptors change shape? ________If the person removed their hand from water, would thermoreceptors change shape? ______

No; Yes

Many choice: By which of the following methods does a cell control the rate of a chemical reaction?

by separating reactants from each other

through the controlling the activity of enyzymes

Muscarinic acetylcholine receptors

Decrease heart rate

The tissue in the heart that generates pressure is composed of

muscle tissue

Important topics in A&P include (choose every correct answer).

homeostasis

the relationship btwn structure and function

Many choice: If you were an evil alien who wanted to paralyze a human and then inflict pain, which of the following toxins could you use? (Choose every correct answer).

A toxin that blocks voltage gated sodium channels in only skeletal muscle fibers

A toxin that blocks voltage gated sodium channels in only efferent neurons

Humans maintain calcium homeostasis. Parathyroid hormone increases blood calcium levels by increasing calcium absorption in the small intestine. Must parathyroid hormone act in the skin to decrease the amount of UV radiation necessary to convert pre-vitamin D3 to vitamin D3?

no

Many choice: Which of the following cells live in lacunae?

osteocytes and chondrocytes

During the relative refractory period, voltage-gated potassium channels are

open

Multiple sclerosis is a disease in which myelination of neurons is disrupted. This is a problem because

Action potentials from non-myelinated neurons are not timed correctly

The equilibrium potential for sodium is about +66 mV. If only sodium channels were open in a cell's plasma membrane, the membrane potential would be

About +66 mV

Blood pressure initially drops when we stand up from the couch. We must maintain blood pressure to maintain oxygen concentration at our brain. Increased cardiac output/heart rate raises blood pressure. How does our body respond to standing up from watching TV? Order the events below, ignoring events that do not occur.

First: a structure changes shape as blood pressure changes

Second: neurotransmitter is released at a synapse btwn two neurons

Third: Epinephrine is released at the heart

Fourth: heart rate increases

Of the steps below, which is the first to occur when we decide to contract the biceps brachii muscle?

A graded depolarization in the muscle fiber

Which of the following cells control the activity of smooth muscle in the gut?

autonomic motor neurons

If we tap the patellar tendon with a hammer, which of the following happens first?

the quadriceps contract

Normally, if a muscle is relaxed we could still not stretch the muscle to injury with moderate force. This is partially due to the presence of proteins and structures we did not study in detail. For the purpose of this question, assume a sarcomere has only the following structures: 1. Z-lines2. Thin filaments3. Thick filaments attached appropriately at M-linesAssume the sarcomere does not have additional structures like titin. In which of the following situations could we stretch the muscle to abnormal lengths using only a little bit of force? Choose every correct answer.

When calcium concentrations surrounding the sarcomere are zero.

Many choice: If we destroyed all sympathetic ganglia but the rest of the nervous system were intact, which of the following changes would occur?

Heart rate during exercise would be lower than normal

.....

Many choice: Disrupting the structure of the skin would directly interfere with which of the following processes?

Defending against pathogens

Maintaining steady body fluid levels

How do forces act on potassium in resting cells?

Electrical gradient pushes in; concentration gradient pushes out

When we accelerate from a stoplight, which of the following cells depolarizes?

hair cells

As a person becomes hot, they become

redder

A neurotransmitter called "GABA" decreases the rate of action potential generation in neurons, but the effect can be overridden by excitatory neurotransmitters. Alcohol binds to the GABA receptor and has the same effect. Alcohol must

Cause hyperpolarization in neurons

Where does integration of sensory information from the eye, ear, and skin occur?

A multimodal association area

Where would you look for osteocytes in a slide of bone tissue?

In lacunae

Which of the following would occur if the skin were simple squamous epithelium?

Bacterial infections would increase.

Insensible water loss would increase.

Gas exchange (breathing) through the skin would increase.

In order for melanin to protect against at least two types of skin cancer, the pigment must be passed to

Epithelial cells

Many choice: Disrupting the structure of the lung would dramatically interfere with which of the following processes?

Maintaining blood oxygen levels

A herniated disc involves damage to

The fibrocartilage between adjacent vertebral bodies

The fastest reflex causing muscle relaxation would involve

two synapses

When blood vessels narrow, they help increase blood pressure. Pretend that all effects on blood pressure must come from changes in smooth muscle in the arm. Using what you know about smooth muscle and the neurotransmitters secreted at blood vessels in the arm, you would know that

Epinephrine increases calcium levels in arm smooth muscle

We see dim objects best when we do not look straight at them.

true

In skeletal muscle, an action potential is most directly caused by opening of

Voltage gated sodium channels

A box of dried pasta can sit on the shelf indefinitely without breaking down, but when we eat the pasta, starch is broken down into water and CO2. Energy stored in the bonds is released. The reason pasta breaks down in our bodies is that

Enzymes in our bodies lower the amount of energy required for chemical reactions to move forward

If we assume our muscles are contracting at a constant speed, which of the following would increase the distance we could kick a soccer ball? Respond by referring only to the action of the prime movers.

Surgically moving the insertion of anterior leg muscles to a more proximal location

Beta 2 adrenergic receptors cause ____________ calcium release in airway smooth muscle

Decreased

Humans must maintain consistent levels of body fluids. Is it necessary for the skin to have receptors that change shape when body fluid volume changes?

No

A cell is placed in a solution containing only urea and water. The cell swells and bursts. The osmolarity of the urea solution is (Urea dissolves in water and diffuses through a cell membrane).

We need more information answer the question

Many choice: Which of the following would cause cells to swell?

pure water

sodium

When a person stands on one foot they tend to wobble rather than remain completely still. Nonetheless, they can maintain this position. Effectors in the feedback loop that allow a person to remain standing on one leg are located in

Muscular tissue

Which of the following changes shape to regulate the amount of light hitting the retina?

Smooth muscle in the iris

A joint stabilized by only muscles and tendons would be ________________ stabile than a joint stabilized by only fibrous connective tissue.

Less

A muscle that originates on the ischial tuberosity and inserts on the head of the fibula would

Flex the knee and extend the hip.

GTP is a high energy molecule like ATP, but we have not studied the function of GTP in cells. GTP binds to proteins and changes their function. Even without further information you know that

When GTP binds a protein, it changes shape.

If humans have no structure that changes shape in the presence of uranium, is it possible to maintain uranium homeostasis?

No

Imagine two muscle fibers. Muscle fiber "A" is a narrow fiber with plenty of mitochondria. Muscle fiber "B" is a thicker fiber with fewer mitochondria per volume. If calcium levels in each fiber were sufficient to cause 1,000 cross bridges to cycle, which fiber would generate the most force?

.... The forces generated by each muscle fiber would be equal??

In an adult, the joint between two parietal bones in the skull is

immoveable

Why does sodium chloride dissolve well in water?

The ionic bonds break because portions of the water molecules attract each ion

Which of the following protein fibers resist stretch, but provide flexibility?

collagen fibers

When pronated, the thumb is ______________ the fifth metacarpal

lateral to

Many choice: Thyroid stimulating hormone (abbreviated TSH) travels through the bloodstream and affects some cells but not others. Without being given any further information you know that

TSH binds to structures and causes them to change shape.

Hydrophobic lipid tails contain

C-C and C-H bonds

If a burn is very painful, it is likely third degree (full thickness).

false

Many choice: The structural properties of epithelial tissue are primarily due to the structure of

the cells that make up the tissue

Signals from the right eye travel to only the left primary visual cortex.

false

If a person injured the fibrocartilage of an intervertebral disc but spinal nerves and the bone were not affected, would the injury cause pain?

no

Which of the following would increase the force generated by a skeletal muscle? Choose every correct answer.

Increasing the rate of action potential generation in a lower motor neuron

Increasing the number of lower motor neurons activated

Many choice: Axons in which of the following pathways cross at the level of the entering spinal nerve?

Lateral spinothalamic

Stratified squamous epithelial cells are effectors in a feedback loop that helps maintain temperature homeostasis.

false

Does acetylcholine always cause depolarization of its target cell?

no

Many choice: Imagine the situation pictured below. Myosin molecules are stuck to a glass plate in a solution containing complete thin filaments (thin filaments with troponin and tropomyosin). The solution looks like the sarcoplasm. Which of the following would have to be added to the solution for myosin to make the thin filaments move. Choose every correct answer.

ATP

....

Where are cells that detect rotation of the head?

semicircular canals

Does a solution that contains only water and glucose conduct electricity?

no

Imagine a probe that secretes a chemical that activates pain receptors. Prior to a stimulus, the probe is inserted into the medial meniscus by a method that causes no pain. When the probe is suddenly turned on, would it initiate a reflex?

no

Many choice: Which of the following are effectors in the feedback loop that helps maintain blood calcium homeostasis?

kidney

osteoclasts

Many choice: Cranial nerves may be

Sensory only

Motor only

Mixed

Where are cell bodies lower motor neurons?

anterior gray horn of spinal cord