Question

1. a substance that is released into the blood by an endocrine gland is called a: (3.1)

a) neurotransmitter
b) protein
c) hormone
d) steroid

1. there are two structural types of hormones found in the human body, they are: (3.2)

a) cholesterol and amine
b) steroid and protein
c) endocrine and exocrine
d) internal and external

1. which of the following is true regarding the glands of the endocrine system? (3.5)

a) they tend to all be very large organs
b) they are very close to each other in the body
c) they all contribute to digestion
d) they are many small organs, found spread throughout body

1. the cells or organs the hormone has its desired effect on are called:

a) effector/target cells or organs
b) endocrine glands
c) hormones
d) sensory neurons

Explanation:

1. Hormones are substances released by endocrine glands into the blood to regulate various body functions. Neurotransmitters are involved in nerve - to - nerve communication, proteins are large biological molecules with many functions not specific to endocrine release, and steroids are a type of hormone but not the general term for endocrine - gland secretions.
2. The two main structural types of hormones in the human body are steroid and protein. Cholesterol is a precursor for some steroids but not a hormone type on its own, amine is a type of neurotransmitter and some hormones, endocrine and exocrine are types of glands, not hormone structures, and internal and external are not relevant structural hormone types.
3. Endocrine glands are many small organs spread throughout the body such as the thyroid, pancreas, etc. They are not all large organs, not all very close to each other, and do not contribute to digestion (digestive function is mainly of exocrine glands and digestive organs).
4. The cells or organs on which a hormone exerts its desired effect are called effector or target cells or organs. Endocrine glands produce hormones, hormones are the messengers, and sensory neurons are involved in sensing and transmitting sensory information, not in being the target of hormones.

Answer:

1. c) Hormone
2. b) Steroid and protein
3. d) They are many small organs, found spread throughout body
4. a) Effector/target cells or organs