Why Doesn't Every Cell in the Body Respond to Every

question 23

Multiple Choice

Why doesn't every cell in the body respond to every hormone circulating in the bloodstream?

• A) Each cell has a limited number of protein channels that shuttle hormones through its membrane.
• B) Not all hormones can diffuse through all cell membranes.
• C) The concentration of some hormones is too low to stimulate every cell.
• D) Each cell has specific surface receptors, which interact only with hormones that they recognize.
• E) Although all hormones bind to all cell surfaces, some cells lack second messengers for expression.

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Definitions:

Organ Systems

Groups of organs working together to perform complex functions necessary for the survival and homeostasis of an organism.

Embryonic

Relating to the earliest stages of development in living organisms before birth or hatching.

Implantation

Attachment of the blastocyst to the endometrium of the uterus, occurring 6 or 7 days after fertilization of the ovum.

Human Embryo

An early developmental stage of human growth and differentiation, starting from fertilization to the eighth week, where major organs and structures begin to form.