問題一覧
1
Homeostasis is best defined as:
The maintenance of a stable internal environment
2
Which statement best explains the role of negative feedback mechanisms in biological systems?
Negative feedback mechanisms reduce fluctuations and help maintain homeostasis by reversing any deviation from the set point
3
Which statement best explains the role of positive feedback mechanisms in biological systems?
Positive feedback mechanisms help to amplify responses or processes, leading to a rapid or more pronounced effect until a specific outcome is achieved
4
Paracrine signaling involves:
Short-distance communication between nearby cells
5
Which statement correctly describes signaling via gap junctions?
It facilitates rapid communication by permitting the direct passage of ions or small molecules between neighboring cells
6
Endocrine signaling involves:
Long-distance communication via the bloodstream
7
What is the usual outcome when a ligand binds to its receptor?
The receptor's shape or activity is altered, initiating a cellular response
8
Intracellular receptors typically bind:
Small, hydrophobic ligands
9
What is a characteristic function of G protein-coupled receptors (GPCRs)?
They utilize G proteins that bind GTP and GDP
10
What is a primary function of ligand-gated ion channels in cellular processes?
They open or close in response to the binding of a specific molecule, allowing ions to flow across the membrane
11
Where is the pituitary gland situated in the body?
At the base of the brain
12
Which statement is true about the anterior pituitary?
It produces its own hormones, regulated by the hypothalamus
13
Which statement is true about the posterior pituitary?
It stores and releases hormones produced by the hypothalamus
14
Which statement accurately describes the hypothalamic-pituitary portal system?
It allows for the direct transport of hypothalamic hormones to the anterior pituitary
15
Which hormone is NOT produced by the anterior pituitary?
Oxytocin
16
Which statement is true regarding prolactin (PRL)?
It stimulates milk production
17
How does the hypothalamus regulate the function of the anterior pituitary?
By secreting releasing hormones that stimulate the anterior pituitary and inhibiting hormones that suppress its activity
18
What is a primary function of oxytocin often referred to as the "love hormone"?
It promotes bonding and social interactions, as well as facilitating childbirth and breastfeeding
19
Which statement accurately describes the pancreas?
It is both an exocrine and an endocrine gland
20
Which of the following statements correctly distinguishes between endocrine and exocrine glands?
Endocrine glands secrete hormones directly into the bloodstream, while exocrine glands release their products through ducts to external surfaces or cavities
21
What is the primary function of the islets of Langerhans in the pancreas?
They produce hormones such as insulin and glucagon that regulate blood sugar levels
22
Which statement is true about insulin?
It promotes glucose uptake by cells
23
Which statement accurately describes the function of glucagon?
It stimulates glycogen breakdown in the liver
24
Which statement correctly describes the function of somatostatin?
It dampens the extremes of insulin and glucagon effects
25
Which statement is true about the adrenal cortex?
It is regulated by ACTH from the anterior pituitary
26
Which statement is true regarding the adrenal medulla?
It is directly activated by the sympathetic nervous system
27
Which statement accurately describes the primary function of mineralocorticoids, such as aldosterone?
They control the balance of electrolytes and water
28
Which statement correctly describes the primary role of glucocorticoids, such as cortisol?
They assist in managing the body's response to stress
29
What is the primary function of epinephrine produced by the adrenal gland?
It increases heart rate and enhances blood flow to muscles during stress
30
Which of the following statements accurately describes the zona glomerulosa of the adrenal gland?
It is the outermost layer and primarily produces mineralocorticoids like aldosterone