High School Biology : Understanding Specific Hormones

Study concepts, example questions & explanations for High School Biology

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Example Questions

Example Question #7 : Endocrine System

How does antidiuretic hormone perform its function?

Possible Answers:

Makes the collecting duct permeable so that water can exit the filtrate

Constricts the kidneys to keep them from filtering blood

Reabsorbs salts so that water passively diffuses out of the filtrate

Constricts the ureter to keep fluids from flowing into the bladder

Expands the bladder so that more urine can be carried by the body

Correct answer:

Makes the collecting duct permeable so that water can exit the filtrate

Explanation:

Antidiuretic hormone (ADH) is a hormone released by the posterior pituitary when there is an imbalance of water in the body. Its function is the same as aldosterone, which also helps regulate water levels in the body. ADH causes channels to open in the collecting duct for water to exit the filtrate and enter the blood, increasing blood volume and retaining water.

In contrast, aldosterone causes channels to open for sodium to exit the filtrate and enter the blood. The blood becomes more concentrated, which draws water out of the filtrate to help dilute the increased sodium levels. This also leads to increased blood volume and water retention.

Example Question #42 : Organs And Organ Systems

Which of the following hormones has the opposite effect of parathyroid hormone?

Possible Answers:

Calcitonin

Glucagon

Insulin

Antidiuretic hormone

Correct answer:

Calcitonin

Explanation:

Parathyroid hormone is responsible for increasing blood calcium levels. Calcitonin has the opposite effect, and lowers blood calcium levels. These two hormones act in a negative feedback loop to keep calcium levels relatively constant. When calcium levels are high, calcitonin is released. When calcium levels are low, parathyroid hormone is released.

Insulin serves to low blood glucose levels, while glucagon acts to increase blood glucose. Antidiuretic hormone (ADH) helps conserve water in the body by increasing water reabsorption in the kidneys.

Example Question #1 : Endocrine System

The primary function of insulin is __________.

Possible Answers:

to decrease blood sugar levels

to stimulate the fight or flight response

to stimulate uptake of glucose by cells

Two of these answers are correct.

to increase blood sugar levels

Correct answer:

Two of these answers are correct.

Explanation:

Insulin stimulates the reuptake of glucose from the blood into the cells. Thus, the glucose levels in the blood decrease, as the glucose is taken into cells. The cells may either store it as glycogen (in liver and skeletal muscle) or use it in glycolysis to make ATP.

Example Question #751 : High School Biology

Epinephrine has which of the following effects on the body?

Possible Answers:

Constriction of blood vessels serving skeletal muscles

Constriction of the pupils

Dilation of the blood vessels serving the gastrointestinal organs

Dilation of the windpipes in the lungs

None of the other answers is correct.

Correct answer:

Dilation of the windpipes in the lungs

Explanation:

Epinephrine is the hormone that gets you ready for a "fight or flight" response. This means increasing heart rate, increasing the force of heart contractions, increasing blood flow to the muscles, and opening the windpipes. This would help you if you needed to run away or fight by increasing the amount of oxygen thats delivered to the blood. Also, during a fight, flight, or freight response, the pupils dilate to allow more light to enter, making it easier to see in the dark. 

Example Question #752 : High School Biology

Which of the following is not an effect of insulin?

Possible Answers:

Inhibiting the release of glucagon

Decreasing blood glucose levels

Glucose uptake by adipose (fat) cells

Glucose uptake by muscle cells

Gluconeogenesis in the liver (liver makes glucose)

Correct answer:

Gluconeogenesis in the liver (liver makes glucose)

Explanation:

Insulin functions to decrease blood sugars. It does so by acting on adipose tissue to uptake glucose. It causes increased glucose utilization by the muscles. It also inhibits the release of glucagon, which has the opposite effects as insulin. 

Gluconeogenesis by the liver occurs in response to very low blood glucose, when the body is in need of sugar. Glucagon causes gluconeogenesis in the liver. 

Example Question #753 : High School Biology

Which hormone acts to increase the levels of serum calcium (calcium flowing in the blood)?

Possible Answers:

Parathyroid hormone (PTH)

Progesterone

Cortisol

Aldosterone

Calcitonin

Correct answer:

Parathyroid hormone (PTH)

Explanation:

Parathyroid hormone is secreted by the parathyroid gland in response to low levels of serum calcium. It acts to increase the resorption of calcium from the bone, kidneys, and intestines. Note that vitamin D is also a hormone that shares this function.

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