BIO 1243 EXAM 4 REVIEW 2025/2026
QUESTIONS AND ANSWERS 100% PASS
What are the two systems for internal communication in animals? - ANS Nervous system and
endocrine system
What is a chemical messenger? - ANS A type of molecule that is secreted by cells and
influences the actions of other cells
What is the process by which hormones affect a particular cell? - ANS Signal is sent, signal is
received, cell responds
What are endocrine cells? - ANS Cells that secrete hormones
What are target cells? - ANS Cells that receive signals from hormones
What is the effect of hormones on target cells? - ANS To alter the animal's physiology and
help maintain homeostasis
What are pheromones? - ANS Chemical messengers that are transported outside of an
animal and can cause behavioral or physiological changes in another individual
1 @COPYRIGHT 2025/2026
, What are the differences between peptide/protein hormones and steroid hormones? -
ANS Peptide/protein hormones are water-soluble and cannot pass through cell membranes,
while steroid hormones are lipid-soluble and can pass through cell membranes
Where do peptide/protein hormones bind? - ANS To receptors embedded within the cell
membrane
Where do steroid hormones bind? - ANS To receptors located within the cytoplasm or
nucleus of the cell
What happens when a hormone-receptor complex enters the nucleus? - ANS It may bind to
DNA and influence gene expression
What is the role of the hypothalamus? - ANS To control the pituitary gland and serve as a
liaison between the nervous and endocrine systems
What is the pituitary gland? - ANS A gland attached to the hypothalamus that releases
hormones.
What are the two parts of the pituitary gland? - ANS Posterior pituitary and anterior
pituitary.
What hormones are released by the posterior pituitary? - ANS Oxytocin and antidiuretic
hormone (vasopressin).
What hormones are released by the anterior pituitary? - ANS Numerous hormones.
What is the function of oxytocin? - ANS Facilitating birth, milk production, and forming social
attachments.
2 @COPYRIGHT 2025/2026
QUESTIONS AND ANSWERS 100% PASS
What are the two systems for internal communication in animals? - ANS Nervous system and
endocrine system
What is a chemical messenger? - ANS A type of molecule that is secreted by cells and
influences the actions of other cells
What is the process by which hormones affect a particular cell? - ANS Signal is sent, signal is
received, cell responds
What are endocrine cells? - ANS Cells that secrete hormones
What are target cells? - ANS Cells that receive signals from hormones
What is the effect of hormones on target cells? - ANS To alter the animal's physiology and
help maintain homeostasis
What are pheromones? - ANS Chemical messengers that are transported outside of an
animal and can cause behavioral or physiological changes in another individual
1 @COPYRIGHT 2025/2026
, What are the differences between peptide/protein hormones and steroid hormones? -
ANS Peptide/protein hormones are water-soluble and cannot pass through cell membranes,
while steroid hormones are lipid-soluble and can pass through cell membranes
Where do peptide/protein hormones bind? - ANS To receptors embedded within the cell
membrane
Where do steroid hormones bind? - ANS To receptors located within the cytoplasm or
nucleus of the cell
What happens when a hormone-receptor complex enters the nucleus? - ANS It may bind to
DNA and influence gene expression
What is the role of the hypothalamus? - ANS To control the pituitary gland and serve as a
liaison between the nervous and endocrine systems
What is the pituitary gland? - ANS A gland attached to the hypothalamus that releases
hormones.
What are the two parts of the pituitary gland? - ANS Posterior pituitary and anterior
pituitary.
What hormones are released by the posterior pituitary? - ANS Oxytocin and antidiuretic
hormone (vasopressin).
What hormones are released by the anterior pituitary? - ANS Numerous hormones.
What is the function of oxytocin? - ANS Facilitating birth, milk production, and forming social
attachments.
2 @COPYRIGHT 2025/2026
