Structure and Function of the Systems Flashcards
Which of the following is not a component of the central nervous system (CNS) ?
cranial nerves
Gaps in the myelin sheath of neurons are known as __
nodes of ranvier
Which of the following has the greatest influence on resting membrane potential?
potassium leak currents
Oligodendrocytes are found in the __
central nervous system
Which of the following is an effect of sympathetic stimulation of the liver?
increased glycoogenolysis
What is the resting potential of a neuron?
-70mV
Place the following sections of an action potential in order:
- Na+ channels open
- Na+ channels close and K+ channels open
- K+ channels close
A sensory neuron of the PNS takes impulses to __
the spinal cord
Which of the following is not true regaurding the somatic nervous system?
it is regulated by both acetylcholine and epinephrine
The part of the peripheral nervous system which directs the body’s rapid involuntary response to danger or stress is the __
sympathetic nervous system
An action potential arrives at the axon terminal at a synaptic junction. Which of the following events then causes release of a neurotransmitter into the synaptic cleft?
Ca2+ uptake at the axon terminal
Voluntary skeletal muscle contraction is controlled by which part of the brain?
frontal lobe of the cerebral cortex
Which of the following is released at the synapse between a somatic motor neuron and a muscle fiber to stimulate muscular contraction?
acetylcholine
Which of the following best describes the function of myelin in a neuron?
increases the speed of nerve signal transmission
Which of the following best describes what happens to excess neurotransmitter in the synapse following synaptic transmission?
is it absorbed by the presynaptic neuron
Place the following sections of synaptic transmission in order:
- nerve signal arrives at the axon terminal (pre)
- Ca2+ channels open in presynaptic membrane
- Ca2+ enters the axon terminal
- neurotransmitter is released into the synaptic cleft
- neurotransmitter binds to postsynpatic membrane
Which of the following membrane potentials represents the approximate peak depolarization of the action potential of a neuron?
+40mV
The part of the peripheral nervous system which regulates involuntary bodily functions such as heart rate, blood pressure and respiration is the __
autonomic nervous system
Which of the following amino acids also functions as a CNS neurotransmitter?
glutamate
Which of the following affects on the action potential may result if the relative stimulation of a neuron increases?
the action potentials increase in frequency
Epinephrine and norepinephrine hormones are derived from __
tyrosine
The effect of somatostatin on glucose metabolism is __
decreased glycogenolysis and glycogen synthesis
Which of the following hormones enters the target cell rather than binding to transmembrane receptors?
estrogen
Insulin is produced by __
beta cells in the pancreas
Which of the following is a hormone which increases the body’s basal metabolic rate?
thryoxine
Which of the following is classed as both an endocrine and exocrine gland?
pancreas
Which of the following hormones increases in the bloodstream if you skip breakfast and go for a run?
glucagon
Which of the following is a pituitary gland hormone which stimulates sperm production in males and follicle development in females?
FSH
Which of the following is not a peptide hormone?
aldosterone
Which of the following describes the difference endocrine and exocrine glands?
endocrine glands release hormones directly into the bloodstream without ducts whereas exocrine glands release secretions into ducts
Which if the following hormones does not increase Ca2+ levels in the blood?
calcitonin
Which of the following is/are glands found just above the kidneys?
adrenal glands
Which of the following is considered the link between the nervous and endocrine systems?
hypothalamus
Which of the following is a type of cell signaling in which one cell affects nearby target cells?
paracrine
Which of the following does not have exocrine function?
adrenal glands
Which of the following is a group of hormones released from the adrenal glands in response to stress?
catecholamines
Which of the following glands does not synthesize its own hormones?
posterior pituitary
Which of the following describes the function of oxytocin?
stimulates milk letdown in the breasts
Which of the following describes the physiological effects of hypothyroidism?
lower heart rate and respiration rate
Which of the following describes the effect of calcitonin on bone calcium stores?
decreased osteoclasts number and activity
Which of the following statements is incorrect regarding luteinizing hormone (LH)?
LH activates GnRH production
Which of the following two hormones are stored and released by the posterior pituitary gland?
vasopressin and oxytocin
Which of the following is not a hormone secreted by the adrenal gland?
antidiuretic hormone (ADH)
Which of the following best describes the overall function of the thyroid gland?
regulation of cell growth and metabolism
Which of the following is not under hypothalamic control?
regulation of the immune response
A tropic hormone is one which __
stimulates endocrine glands
Which of the following is the primary target for tropic hormones of the hypothalamus?
anterior pituitary
Which of the following shows the passage of air into the lungs?
nose-> larynx-> trachea-> bronchi-> bronchioles-> alveoli
The term “low oxygen binding affinity” means that hemoglobin
unloads oxygen easily but does not readily load
The majority of carbon dioxide in the blood is transported as __
HCO3-
What is the function of the pulmonary surfactant produced by type 2 epithelial cells in the alveoli?
to prevent alveoli from collapsing during exhaling
Which of the following is the driving force which causes air to enter the lungs during inhalation?
lower pressure in the lungs than the atmosphere
Diaphragmatic contraction is stimulated by the
phrenic nerve
Which of the following describes the effect of high partial pressure of oxygen on the binding affinity of hemoglobin?
higher affinity
2,3- disphosphoglycerate is synthesized in the blood in response to __
low blood oxygen levels
Which of the following explains why hemoglobin readily unloads carbon dioxide in pulmonary capillaries?
Haldane effect
Which of the following statements about chloride ions in the blood plasma is correct?
oxygenated blood has more chloride ions than deoxygenated blood
The function of chloride ions in the blood is
to allow bicarbonate to cross the red blood cell membrane
The medulla oblongata regulates ventilation by
detecting changes in blood pH using chemoreceptors
Congestive heart failure often leads to acidosis of the blood. Which of the following is the primary cause of this decrease in blood pH?
decreased rate of diffusion of CO2 from the capillaries into alveoli at the lungs
Which of the following explains why hemoglobin readily unloads oxygen at respiring tissues?
Bohr effect
Hyperventilation will result in which of the following conditions?
respiratory alkalosis
Which of the following would not be an effect of a decrease in carbon dioxide concentration in the blood?
bronchodilation
Which of the following ions must be bound to hemoglobin in order for it to load oxygen?
Fe2+
As CO2 partial pressure increases, the affinity of hemoglobin for oxygen __ causing __ shift in the saturation curve
decrease, right
Which of the following shows the path of oxygenated blood leaving the lungs?
pulmonary vein-> left atrium-> left ventricle-> aorta
Which of the following describes the function of the AV node?
to decrease the speed of the electrical impulse passing between the SA node and the Bundle of His
Deoxygenated blood from the head and arms returns to the heart via the __
superior vena cava
Which of the following vessels connects capillaries and veins?
venules
The pulmonary circuit begins in the __ and ends in the __
right ventricle, left atrium
Which of the following shows the pathway of electrical stimulation through the heart?
SA node-> AV node-> Bundle of His-> Purkinje fibers
Which of the following are innervated by sympathetic nerves?
arteries and arterioles
Lymph flows through lymphatic vessels due to __
both contraction of skeletal muscles and contraction of smooth muscle in lymph vessel walls
Stimulation of the sinoatrial node by the vagus nerve would result in __
slower heart rate
Which event follows electrical stimulation of the Purkinje fibers?
ventricular contraction
Which of the following would not serve to relieve hypertension?
decreased urine production
Portal circulation of blood occurs between which of the following?
separate capillary beds
Which of the following is not a component of lymph?
erythrocytes
During ventricular systole, which valves of the heart open?
aortic and pulmonary
Which of the following is a direct effect of the AV node failing?
the ventricles would not contract
Cardiac output refers to __
the volume of blood pumped out of the hart per minute
Which of the following best describes the structure of arterioles?
they are small with a layer of smooth muscles on the outside
End Diastolic volume refers to __
the volume of the blood in the ventricles before contraction
Which of the following has the greatest effect on systemic blood pressure?
arterioles
Which blood vessels have walls which contain smooth muscles?
arteries, veins, and arterioles
Of the plasma proteins thrombin and prothrombin __
thrombin is the active form and prothrombin is the inactive form __
The function of the thoracic duct is the __
drainage of lymph into the bloodstream
Which of the following is an enzyme found in saliva which kills bacteria?
lysozyme
In the case of tissue damage or infection, monocytes differentiate into __
macrophages
Which of the following is not initially involved in the immune response when a pathogen is encountered by the body for the first time?
T lymphocyte
Neutrophils migrate towards injured or infected tissue following a chemical gradient in a process known as __
chemotaxis
Which of the following is a differentiated B or T lymphocyte which responds relatively more quickly to subsequent encounters with a pathogen?
memory cell
Which of the following is not involved in the adaptive (specific) immune response?
neutrophil
Recognition of self verses non self cells by the adaptive immune system occurs due to the exposure of T cells to __
bodily antigens in the thymus
Which of the following best describes the action of complement proteins in immune response?
lysis of foreign cells
In which part of an antibody would you expect to find the antigen binding sites?
variable region
Which of the following best describes the function of plasma cells in the immune response?
synthesis of antibodies
Antibodies are crucial components of the adaptive immune response. Which of the following is not a function of antibodies?
antigen presentation
Which of the following best describes cell mediated immunity?
an immune response mediated by helper and cytotoxic T cells
Which of the following is not a component of gastric juices?
bile
Which of the following is secreted by salivary glands?
amylase
Which of the following best describes the effect of glucagon on the body?
increase the release of glucose into the bloodstream by the liver
Which of the following secretes hydrochloric acid in the stomach?
parietal cells
Which of the following best describes the primary function of gastrin in digestion?
stimulate hydrochloric acid secretion in the stomach
The inactive pre cursors of digestive enzymes are known as __
zymogens
Which structure in the small intestine transports fatty acids and glycerol into the lymph?
lacteals
Which of the major food groups is biochemically digested in the mouth, stomach, and small intestine?
carbohydrate
Which of the following is secreted by the pancreas to neutralize stomach acids as food travels into the small intestine?
bicarbonate
Which of the following describes a primary function of the large intestine?
absorption of water, electrolytes and vitamins
Which of the following is involved in the chemical digestion of proteins in the small intestine?
trypsin
Which of the following may be used as a source of energy during times of starvation?
muscle tissue, ketone bodies, glycogen, adipose tissue
Which of the following prevents stomach walls from self digestion
mucous cells
Which of the following is secreted by the duodenum to stimulate bicarbonate secretion from the pancreas?
secretin
The formation of glycogen from glucose is known as __
glycogenesis
Which of the following is secreted to stimulate the production of gastric acid?
histamine
What is the function of bile during digestion of fats?
emulsifying larger fat droplets into smaller fat droplets
Countercurrent exchange in the kidney occurs in the __
loop of henle
Which of the following shows the correct passage of urine out of the body?
kidneys-> ureter-> bladder-> urethra
In the nephron chloride ions __ the ascending limb of the Loop of Henle by __
leave, active transport
Which of the following describes the function of the juxtaglomerular apparatus?
regulation of blood pressure
Which of the following is unlikely to be presents in the urine produced by a normally functioning kidney?
glucose
The driving force for ultrafiltration of blood in the glomerulus is
hydrostatic pressure in the glomerular capillaries
As fluid moves through the descending limp of the loop of henle it becomes
more concentrated
Which of the following shows the correct passage of blood through they kidney?
afferent arteriole-> efferent arteriole-> peritubular capillaries
Compared to the filtrate, the renal medulla is __ and the renal cortex is __
hypertonic, hypotonic
Where in the nephron does the greatest reabsorption of amino acids from filtrate occur?
proximal convoluted tubule
The osmolarity gradient in the medulla is established by __
selective permeability of the loop of henle
The purpose of ammonia in excretion is to __
acid base homeostasis of the body
The rate of ultrafiltration in the glomerulus is determined by __
the osmolarity of the blood, the rate of flow of blood flow to the kidney, the relative sizes of the afferent and efferent arterioles
If the flow rate of filtrate through the nephron increases __
urine will become more dilute
Which of the following explains the effect of aldosterone on the nephron?
increased membrane permeability of the distal convoluted tubule to sodium
Which of the following would occur as a result of an increase in the concentration of plasma potassium?
aldosterone secretion
Which of the following shows the correct order of the phase of the ovarian cycle?
follicular phase, ovulation, luteal phase
Gonadotropin hormones are produced in the __
anterior pituitary
Menstruation predominantly occurs during which phase of the ovarian cycle?
follicular phase
The main function of LH in both sexes can be describes as __
maturation of germ cells
FSH is predominantly active in females from __ to __
puberty, menopause
Which of the following describes the function of FSH in the male reproductive cycle?
regulating sperm production and maturation
Which of the following hormones directly complements estrogen in the preparation of the endometrium for implantation of a fertilized egg?
progesterone
An LH surge in the ovarian cycle results in __
ovulation
which of the following describes the follicular phase of the female reproductive cycle?
development of the secondary oocyte
In an average 28 day cycle, the proliferative phase occurs approximately during __
days 7-14
The primary source of progesterone during early stages of pregnancy is the __
corpus luteum
During which of the stages of the ovarian cycle is successful implantation most likely to occur?
luteal phase
Which hormone directly inhibits FSH release by the pituitary gland?
estrogen
Increased levels of estrogen during the follicular phase of the ovarian cycle causes which of the following?
thickening of the endometrium
In an average 28 day cycle, the LH surge occurs around day __
13
The corpus luteum produces which of the following?
estrogen and progesterone
Gonadotropin releasing hormone is produced in the __
hypothalamus
the part of the ovarian cycle where menstruation occurs is __
days 1-7
Which of the following is not a function of luteinizing hormone?
estrogen inhibition
Which of the following occurs during the luteal phase of the female reproductive cycle?
thickening of the uterine lining
In which of the following structures does spermatogenesis occur?
seminiferous tubules
Which of the following is the correct sequence for the flow of sperm cells from spermatogensis through ejaculation?
testes, epididymis, vas deferens, urethra
Which of the following produces testosterone?
leydig cells
The function of the prostate gland is __
secretion of buffers, nutrients, and enzymes into semen
Successful implantation of a fertilized egg occurs at which female reproductive structure?
endometrium
Which of the following contributes nutrients and enzymes to semen?
seminal vesicle
Which of the following terms refers to the formation of mature egg cells which begins in the developing ovaries of a female fetus?
oogenesis
In females, the onset of oogenesis occurs __
in the womb
What is/are the products of meiosis I in the ovarian follicles?
secondary oocyte + polar body
In males, the onset of spermatogenesis occurs __
during puberty
The release of secondary oocyte from ovarian follicles is known as __
ovulation
The diploid precursor to sperm cells are known as __
spermatogonia
The haploid product of meiosis II in spermatogenesis is known as __
spermatid
Which of the following events stimulates completion of meiosis II in a secondary oocyte?
fertilization
Which of the following type of muscle which is striated and has multiple nuclei?
skeletal
The membrane bound structure within muscle cells which store calcium is known as the __
sacroplasmic reticulum
The contractile unit of a muscle fiber is known as a __
sarcomere
The term “striated” in relation to muscles refers to __
muscle tissue with repeating units
Which of the following causes the red color of muscle tissue?
myoglobin
Action potentials spread through cardiac muscle via __
gap junctions
Which of the following shortens during muscle contraction?
H zone and I band
During the power stroke of muscle contraction, which of the following is not true?
actin moves away from the M line
Which of the following events causes the myosin head to detach from actin and return to the “cocked” ready position?
ATP binding to myosin head
Which of the following correctly describes the power stroke of muscles contraction?
myosin heads pull actin towards the M line
Which of the following regions of the sacromere is comprised of actin only?
I band
During muscle contraction, crossbridges form between __
actin and myosin
Which of the following describes the role of Ca2+ in muscle contraction?
removes tropomyosin from the myosin binding sites on actin filaments
Energy for the power stroke of muscle contraction is obtained by __
hydrolysis of ATP
Which of the following primarily fills the medullary cavity that runs down the center of an adult femur bone?
yellow bone marrow
Longitudinal bone growth occurs mainly at the __
epiphyseal plate
The cylindrical units of compact bone are known as __
osteons
Cells that break down bone matrix for the reabsorption of calcium are known as __
osteoclasts
The point of attachment of muscle to a movable bone is the __
insertion
Which of the following is not part of the axial skeleton?
pelvis
The small cavities within osteons in which osteocytes are found are known as __
lacunae
Which of the following is the type of joint found in the skull?
synarthrosis
Tissue that connects bone to bone is known as __
ligament
Calcium ions in bones exist largely as __
hydroxyapatite
Mature bone cells which exchange nutrients and waste with the blood are known as __
osteocytes
the main type of cartilage present in the knee joint is __
hyaline cartilage
Which of the following is found in infants and children but not adults?
epiphyseal plates
the cells which secrete cartilage and become embedded in it are known as __
chondrocytes
the epidermis is primarily composed of __
squamous epithelial tissue
Which of the following produces a protective pigment to block UV radiation damage to the skin?
melanocytes
The hypodermis is primarily composed of __
connective and adipose tissue
Which of the following helps the epidermal layer to be waterproof and to prevent water loss?
keratin
Which layer of the skin contains blood vessels, nerve ending, and exocrine glands?
dermis
Which of the following does not have a function in heat retention in the skin?
cutaneous vasoconstriction
Which of the following exerts primary control over cutaneous vasodilation and vasocontriction?
sympathetic autonomic nervous system
