Q: Which of the following equations correctly represents the Nernst equation for calculating the equilibrium potential for an ion?

$$E = \frac{RT}{zF} \ln \left( \frac{[\text{ion}]_{\text{outside}}}{[\text{ion}]_{\text{inside}}} \right)$$

Question 1

Which of the following best describes the difference between endocrine and nervous system signaling?

Accepted Answer

The endocrine system releases hormones into the bloodstream for widespread effects, while the nervous system transmits electrical signals along neurons for rapid, targeted responses.

Question 2

A patient is diagnosed with Graves' disease. Which of the following best explains the underlying cause and a likely symptom?

Accepted Answer

Excessive stimulation of the thyroid by antibodies, causing hyperthyroidism and weight loss.

Question 3

Which of the following hormones is released from the posterior pituitary and acts on the kidneys to regulate water balance?

Accepted Answer

Antidiuretic hormone (ADH)

Question 4

Which of the following best explains why the same hormone, such as epinephrine, can have different effects on different tissues?

Accepted Answer

Different tissues have different types of receptors or signal transduction pathways for the same hormone.

Question 5

Which of the following is a correct sequence for the passage of a sperm cell from its site of production to the outside of the male body?

Accepted Answer

Seminiferous tubule → epididymis → vas deferens → urethra

Question 6

Which of the following best describes the 'two-fold cost' of sexual reproduction?

Accepted Answer

Sexual reproduction produces half as many offspring per generation compared to asexual reproduction.

Question 7

During oogenesis in humans, at which stage is the primary oocyte arrested until puberty?

Accepted Answer

Prophase I

Question 8

Which hormone is primarily responsible for stimulating ovulation in the ovarian cycle?

Accepted Answer

Luteinizing hormone (LH)

Question 9

Which of the following best describes the difference between a neurotransmitter and a neurohormone?

Accepted Answer

A neurotransmitter acts locally at synapses, while a neurohormone is released into the bloodstream for distant effects.

Question 10

Which of the following equations correctly represents the Nernst equation for calculating the equilibrium potential for an ion?

Accepted Answer

$$E = \frac{RT}{zF} \ln \left( \frac{[	ext{ion}]_{	ext{outside}}}{[	ext{ion}]_{	ext{inside}}} ight)$$

Question 11

Which of the following best explains why action potentials travel in only one direction along an axon?

Accepted Answer

Voltage-gated sodium channels become inactivated during the refractory period, preventing backward propagation.

Question 12

Which of the following is a function of the Schwann cells in the peripheral nervous system?

Accepted Answer

They produce myelin sheaths around axons.

Question 13

A patient has low blood calcium levels. Which hormone is likely to be secreted to restore homeostasis, and what is its effect?

Accepted Answer

Parathyroid hormone (PTH); stimulates bone resorption to increase blood calcium.

Question 14

Which of the following best describes the role of the hypothalamus in the endocrine system?

Accepted Answer

It receives information from the nervous system and initiates endocrine responses by releasing hormones that control the pituitary gland.

Question 15

Which of the following is a correct pairing of a neurotransmitter class and an example?

Accepted Answer

Neuropeptides – endorphins

Question 16

Which brain structure is primarily responsible for relaying sensory information to the cerebral cortex?

Accepted Answer

Thalamus

Question 17

Which of the following best describes the difference between negative and positive feedback in hormone regulation?

Accepted Answer

Negative feedback reduces the original stimulus to maintain homeostasis, while positive feedback amplifies the stimulus for a specific outcome.

Question 18

Which of the following best explains why testes are located outside the abdominal cavity in many mammals?

Accepted Answer

To maintain a temperature lower than body temperature, which is necessary for proper sperm development.

Question 19

Which of the following is a correct description of saltatory conduction?

Accepted Answer

Action potentials jump from one node of Ranvier to the next, increasing conduction speed.

Question 20

Which hormone is responsible for stimulating the transformation of the ruptured follicle into the corpus luteum?

Accepted Answer

Luteinizing hormone (LH)

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