Question 1

Which of the following best describes the organization of the human body from simplest to most complex?

Accepted Answer

Cells → Tissues → Organs → Organ systems

Question 2

Which primary tissue type is responsible for transmitting electrical impulses throughout the body?

Accepted Answer

Nerve

Question 3

Homeostasis is best defined as:

Accepted Answer

The process of maintaining a stable internal environment compatible with life

Question 4

Which of the following is NOT a component of negative feedback mechanisms?

Accepted Answer

Amplification of the original stimulus

Question 5

A patient is given a drug that blocks ATP production in cells. Which type of membrane transport would be most directly affected?

Accepted Answer

Active transport

Question 6

Which equation best represents the movement of ions by simple diffusion across a membrane?

Accepted Answer

$$J = -D \, \frac{dC}{dx}$$

Question 7

Which of the following is a characteristic of facilitated diffusion but NOT simple diffusion?

Accepted Answer

Requires a membrane protein carrier

Question 8

A neuron is exposed to a toxin that keeps voltage-gated Na$$^+$$ channels open. What is the most likely effect on the neuron's action potential?

Accepted Answer

The neuron will remain depolarized and be unable to repolarize

Question 9

Which of the following best describes the sequence of channel openings during an action potential?

Accepted Answer

Na$$^+$$ channels open first, then K$$^+$$ channels open

Question 10

Which of the following is a function of the absolute refractory period of the axon membrane?

Accepted Answer

Ensures one-way transmission of action potentials

Question 11

A patient has a genetic defect that prevents the formation of myelin in the central nervous system. Which cell type is most likely affected?

Accepted Answer

Oligodendrocytes

Question 12

Which of the following best describes the difference between afferent and efferent neurons?

Accepted Answer

Afferent neurons carry signals to the CNS; efferent neurons carry signals from the CNS

Question 13

Which of the following is a correct statement about gap junctions?

Accepted Answer

They allow direct passage of ions and small molecules between adjacent cells

Question 14

Which of the following best describes the mechanism of signal transduction for membrane enzymes such as tyrosine kinases?

Accepted Answer

Messenger binds to receptor, receptor dimerizes and autophosphorylates, activating intracellular signaling

Question 15

Which of the following is true about paracrine signaling?

Accepted Answer

The chemical messenger acts on nearby cells

Question 16

Which of the following best describes the process of neurotransmitter release at a chemical synapse?

Accepted Answer

Action potential arrives at axon terminal, Ca$$^{2+}$$ channels open, Ca$$^{2+}$$ enters, neurotransmitter is released

Question 17

Which of the following is a correct sequence for the steps in G protein-linked enzyme activation?

Accepted Answer

Messenger binds receptor → G proteins are activated → G protein activates enzymes (e.g., adenylyl cyclase) → Second messenger produced (cAMP) → Cellular response triggered

Question 18

Which of the following best explains why action potentials are conducted faster along myelinated axons compared to non-myelinated axons?

Accepted Answer

Myelination allows for saltatory conduction, where the action potential jumps between nodes of Ranvier

Question 19

Which of the following is a key difference between graded potentials and action potentials?

Accepted Answer

Graded potentials decay with distance, while action potentials are all-or-none and do not decay

Anatomy & Physiology Study Guide: Cells, Tissues, Membranes, and Neural Signaling

Study Guide - Practice Questions

Study Guide - Flashcards