Test 1 Questions Flashcards
The ability of a specific target cell to respond to a hormone is dependent on:
the specific extracellular or intracellular receptor that binds to the hormone.
What specific molecules are secreted by cells and function to alter or regulate target cell metabolism?
Hormones
Most amino acid-based hormones exert their effects on target cells through the activation of intracellular ____.
second messengers, like cAMP
Which of the following is NOT involved in stimulating the release of hormones from endocrine glands?
A) the action of PTH responding to low calcium ion concentrations
B) the action of one hormone opposing the effects of another on the surface of a cell
C) the action of the anterior pituitary responding to GnRH release
D) the action of sympathetic nerves stimulating cells of the adrenal medulla
B) the action of one hormone opposing the effects of another on the surface of a cell
Which of the following is NOT a factor that affects target cell activation following hormone receptor interaction?
A) synthesis of regulatory molecules within the target cell
B) specific number of receptors for the hormone
C) binding affinity between the hormone and receptor
D) specific blood concentration of the hormone
A) synthesis of regulatory molecules within the target cell
Steroid hormones alter target cell activity by:
binding to hormone response elements on chromatin to initiate protein synthesis via gene expression
Why do hormones cause an amplification effect on target cells, causing them to elicit multiple metabolic responses?
This occurs because activated protein kinases catalyze many reactions, which phosphorylate many molecules
TSH is a water soluble hormone. Which statement BEST describes how TSH causes target cell activation?
A) TSH alters cellular metabolism by acting directly on genes
B) TSH binds to intracellular receptors and travels throughout the cytoplasm as a receptor hormone complex
C) TSH indirectly activates G proteins, causing the synthesis of intracellular secondary messengers
D) TSH traverses the cell membrane to enter the cell and activate intracellular receptors
C) TSH indirectly activates G proteins, causing the synthesis of intracellular secondary messengers
Human blood includes all of the following EXCEPT:
A) water
B) albumin
C) interstitial fluid
D) granulocytes
C) interstitial fluid
Which of the following is a regulatory function of blood?
A) delivery of oxygen to body cells
B) phagocytosis of bacterial cells
C) maintaining pH balance of body fluids
D) transport of metabolic waste
C) maintaining pH balance of body fluids
Erythrocytes can be described by all of the following EXCEPT:
A) they have strong, flexible membranes that allow them to change shape
B) they can easily replicate themselves
C) they are specialized to carry oxygen
D) they have a short lifespan
B) they can easily replicate themselves
What is a protective function of blood?
Preventing blood loss from damaged vessels
What are the fragments of megakaryocytes called?
Thrombocytes
A platelet plug forms when:
thrombocytes release chemicals causing them to aggregate at the site of damage
Which statement is FALSE about monocytes and neutrophils?
A) they are whole cells that cannot transport respiratory gases
B) they are nucleated cells that do not contain hemoglobin
C) they are granulocytes produced via hemopoeisis
D) they phagocytize bacteria
C) they are granulocytes produced via hemopoeisis
Identify the correct order of events necessary for blood coagulation.
Formation of prothrombinase > Prothrombin converts to thrombin > Fibrinogen converts to fibrin
The lymphatic system does NOT:
deliver respiratory gases to the body cells
Which statement best describes lymph transport?
A) lymph transport is only important during illness
B) lymph only contains molecules that must be returned to the blood
C) Chyle is a specific type of lymph that transports digested fats
D) under normal conditions, lymph transport occurs under very high pressure
C) Chyle is a specific type of lymph that transports digested fats
Which lymphatic structure is NOT composed of reticular connective tissue?
Thymus
Antibodies that respond to viruses and toxins are synthesized and released by ?
plasma cells
T/F
Lymphatic capillaries are more permeable than blood capillaries due to their flap-like minivalves.
True
How does age affect the thymus?
The thymus increases in size after birth, then decreases in size from adolescence through old age.
Which lymphatic structure drains lymph directly into the venous blood of the left subclavian vein?
Thoracic duct
T/F
The spleen traps bacteria in crypts, which are invaginations in the splenic tissue.
False
T/F
Dendritic cells are specialized macrophages that help activate T cells.
True
T/F
Blood coagulation is one example of hemopoeisis.
False
T/F
Type O- blood lacks A, B, and Rh antigens on the surface of erythrocytes.
True
T/F
Calcitonin and PTH exhibit a synergistic effect at their target cells.
False
T/F
Each erythrocyte can carry up to four molecules of oxygen.
False
T/F
Prolactin causes milk ejection from the mammary glands.
False
T/F
One immunocompetent B cell functions to respond to several different types of antigens.
False
T/F
Reticular connective tissue allows proliferation and surveillance sites for T cells and B cells.
True
Growth Hormone
Promotes protein synthesis and glycogen catabolism
Aldosterone
Reduces sodium ion excretion via cellular reabsorption in the kidneys
Oxytocin
Stimulates smooth muscle contractions of the uterus during childbirth
Thyroid Hormone
Increases the basal metabolic rate of cells via glucose oxidation
Adrenocorticotropic Hormone (ACTH)
Stimulates adrenal cortex to release cortisol during periods of stress
Progesterone
Promotes breast development and regulates the menstrual cycle
Follicle Stimulating Hormone
Stimulates egg and sperm production
Glucagon
Enhances membrane transport of glucose from the blood into cells
Testosterone
Causes maturation of the male gonads and promotes sex drive
Epinephrine
Dilates bronchioles and causes vasodilation in skeletal muscle
