1. Which hormone stimulates milk production in the breasts during lactation?
A. norepinephrine
B. antidiuretic hormone
C. prolactin Correct
D. oxytocin
Explanation
Prolactin is the hormone responsible for stimulating milk production in the breasts during lactation. It is produced by the pituitary gland and plays a crucial role in the initiation and maintenance of lactation. While norepinephrine, antidiuretic hormone, and oxytocin have roles in various physiological processes, they do not directly stimulate milk production. Therefore, the correct answer is prolactin.
2. What are chemical messengers that control growth, differentiation, and the metabolism of specific target cells called?
A. Hormones Correct
B. Neurons
C. Glands
D. Second messengers
Explanation
Hormones are signaling molecules produced by glands that travel through the bloodstream to target cells, exerting control over processes like growth, differentiation, and metabolism. Neurons are nerve cells responsible for transmitting electrical impulses. Glands are structures that secrete substances like hormones. Second messengers are molecules involved in intracellular signal transduction pathways, amplifying and transmitting signals from the cell membrane to the nucleus.
3. How much air does an adult inhale in an average breath?
A. 500 mL Correct
B. 750 mL
C. 1000 mL
D. 1250 mL
Explanation
An adult typically inhales around 500 mL of air in an average breath. This volume is known as tidal volume, representing the amount of air inspired or expired during normal breathing. Tidal volume plays a crucial role in efficient gas exchange in the lungs and maintaining adequate oxygen levels in the body. It is essential for proper respiratory function and ensuring the body receives the necessary oxygen for cellular respiration and overall metabolism.
4. Which type of cell secretes antibodies?
A. bacterial cell
B. viral cell
C. lymph cell
D. plasma cells Correct
Explanation
Plasma cells are a type of white blood cell specialized in producing and secreting antibodies. Antibodies, also known as immunoglobulins, are vital components of the immune system that help recognize and neutralize pathogens. When the body encounters an antigen, plasma cells are activated to produce and secrete antibodies specific to that antigen. These antibodies bind to the pathogen, marking it for destruction by other immune cells. Therefore, plasma cells are the correct answer as they are specifically designed to produce and secrete antibodies to fight infections.
5. What force primarily drives filtration in the kidneys?
A. osmosis
B. smooth muscle contraction
C. peristalsis
D. blood pressure Correct
Explanation
Filtration in the kidneys is primarily driven by blood pressure. The glomerulus filters blood under pressure, allowing small molecules and fluids to pass through into the renal tubules while retaining larger molecules like proteins. Osmosis, smooth muscle contraction, and peristalsis do play roles in kidney function, but blood pressure is the main force responsible for the initial filtration process.