Cell Biology Answers

How is the energy radiated to Earth from the sun captured for use by life-forms on Earth?

Choices are:

It is captured by the inorganic substances found on Earth.

It is absorbed as heat by Earth and this is converted to energy used by life-forms.

It is captured by animals that subsequently make it available to plants.

It is captured by photosynthetic organisms.

What is the definition of "nutrients"?

Choices are:
Nutrients are the heat, light, and ultraviolet rays that reach Earth, which are utilized in chemical reactions to power life

Nutrients are atoms and molecules that organisms obtain from their living or nonliving environment and that are required for survival.

Nutrients are the pigment molecules that absorb specific wavelengths of sunlight, which subsequently store energy in chemical bonds.

Nutrients are molecules that collect and store energy

Which of the following answer choices is a true statement?

The pituitary gland has multiple functions related to the endocrine system.
Secretory cells of an endocrine gland are embedded in muscle tissue.
An endocrine gland is a cluster of hormone-secreting cells surrounded by a network of capillaries.
Target cells produce hormones that are transported throughout the body by the circulatory system.

The kidneys detect low blood oxygen levels and respond by releasing the hormone erythropoietin, which stimulates the bone marrow to make more red blood cells. As a result, the number of red blood cells increases, so more oxygen is carried in the blood. This is an example of which of the following?

positive feedback
synaptic feedback
neutral feedback
negative feedback

Which of the following hormones is a major player in the regulation of appetite?


atrial natriuretic peptide
thymosin
melatonin
leptin

The pancreas is often described as a dual-function gland because it has both endocrine and exocrine functions. What is its exocrine function?

to regulate the amount of calcium in the bloodstream
to promote digestion by releasing bicarbonate and enzymes into the small intestine
to regulate the amount of water in the bloodstream
to absorb vitamins from nutrients passing through the small and large intestines

Islet cells from a donor are injected into a patient with diabetes. If successful, the donor islet cells would release insulin into the bloodstream to regulate blood glucose levels. Why would this treatment NOT cure type 2 diabetes?

islet cells would produce only insulin, not glucagon, which would also be required to regulate blood glucose
in type 2 diabetes, glycogen is lacking, not insulin
islet cells would produce digestive enzymes instead of insulin
in type 2 diabetes, insulin is still produced, but the target cells do not respond

Perchlorate is a synthetic organic component of rocket fuel that contaminates much of our milk and produce, according to government test data. When perchlorate gets into your body it mimics iodine, which the thyroid gland needs to produce thyroxine. Thus, perchlorate is classified as a(n) __________.

receptor activator
enzyme
antibiotic
endocrine disruptor

Which of the following is an accurate statement about the regulation of carbohydrate metabolism in humans?

Insulin reduces the blood glucose level, and glucagon increases it.
Glucagon decreases blood glucose, and insulin increases it.
Parathyroid hormone increases the blood glucose level, and calcitonin decreases it.
FSH increases blood glucose, and LH decreases blood glucose.

What hormone, when injected into virgin female rats, causes them to exhibit maternal behaviors, such as building a nest?

thyroxine
oxytocin
insulin
adrenocorticotropic hormone