NU 545 UNIT 1 EXPECTED QUESTIONS WITH VERIFIED
ANSWERS
Question 1.
What are cytokines?
ANSWER
Growth factor, also called cytokines, stimulate an increase in cell mass or cell growth by
promoting the synthesis of proteins and other macromolecules and inhibiting their
degradation (p. 38)
Cytokines constitute a large family of small-molecular-weight soluble intracellular-signaling
molecules that are secreted, bind to a specific cell membrane receptors, and regulate innate or
adaptive immunity; either proinflammatory or anti-inflammatory. Majority of important
cytokines are classified as interleukins or interferons (p. 201)
Question 2.
Does estrogen affect lymphocytes?
ANSWER
Estrogens generally are associated with a depression of T-cell-dependent immune function and
an enhancement of B-cell functions. (pg. 338)
Question 3.
What is chemical signaling?
ANSWER
Primary means of cell-to-cell communication. 5 forms of signaling mediated by secreted
molecules: (1) Contact-dependent signaling requires cells to be in close membrane-membrane
contact; (2) Paracrine signaling- cells secrete local chemical mediators that are quickly
absorbed, destroyed, or immobilized; (3) Autocrine signaling- cells produce signals that they,
themselves, respond to (cancer cells); (4) Hormonal signaling involves specialized endocrine
cells that secrete chemicals called hormones (TSH). Hormones are released by one set of cells
and travel through the tissue and through the bloodstream to produce a response in other
sets of cells; (5) Neurohormonal signaling- hormones are released into the blood by
neurosecretory neurons. (p.19)
,Question 4.
What is active transport?
ANSWER
requires life, biologic activity, and the cell's expenditure of metabolic energy. Unlike passive
transport, active transport occurs across only living membranes that have to drive the flow
"uphill" by coupling it to an energy source (p. 28)
Question 5.
What happens to liver cells when a portion of the liver is removed?
ANSWER
When liver cells are compromised, new cells can regenerate from intrahepatic stem cells.
Compensatory hyperplasia is this adaptive mechanism that enables certain organs to
regenerate. If part of the liver is removed it leads to hyperplasia of the remaining
cells(hepatocytes) to compensate for the loss. Even if 70% of the liver is removed it only takes 2
weeks for complete regeneration. Hepatocytes usually live approximately a year or more, and
through a very slow rate of cell division they renew themselves. If large number of hepatocytes
are lost due
to surgery or injury; a burst of rapid cell division occurs from the surviving hepatocytes to
replace the lost tissue. (p49)
Question 6.
What is the process of repair after tissue damage?
ANSWER
Occurs in 3 phases and leads to either regeneration (complete return to normal structure and
function) or repair (replacement of destroyed tissue with scar tissue and results in loss of
function) (pg. 212)
Phase I - Inflammation
Inflammatory phase - "coagulation and infiltration of cells that participate in wound healing"
Debridement - by fibrinolytic enzymes, remaining debris drained away by blood vessels and
lymphatics.
Phase II - Proliferation and New tissue formation (Reconstruction) "Epithelization includes
formation of granulation tissue, inward migration of fibroblasts, and the beginning of collagen
synthesis and secretion. Granulation issue becomes scar tissue, contraction begins, and
differentiation begins." (pg. 212, 213)
Phase III - Maturation Phase
tissue regeneration and wound contraction continue. Capillaries disappear from scar tissue.
(pg. 213, 214)
, Question 7.
Which hormone helps to explain the mood cycles, anxiety, and eating disorders in women?
ANSWER
Estrogen (pg. 336)
Question 8.
After sexual transmission of HIV, a person can be infected yet seronegative for how long?
ANSWER
Seronegative = without antibodies; Antibodies can be detected 18-90 days post infection
Question 9.
Know about the effects of fetal alcohol syndrome on infants.
ANSWER
Diagnosis of FAS requires all three facial abnormalities: short palpebral fissure lengths, smooth
philtrum and thin upper lip. FAS may have abnormal facial features, growth problems, CNS
problems, issues with learning, memory, attention, vision, hearing. Pg 70
Question 10.
Where do lipids accumulate?
ANSWER
Although lipids sometimes accumulate in heart and kidney cells, the most common site of
intracellular lipid accumulation, or fatty change, is liver cells. Pg 84
Question 11.
What acts as
a reservoir in which HIV can be relatively protected from antiviral drugs?
ANSWER
Antiviral drugs do not cure HIV because the infected cells act as a reservoir.
The main infected cell is the CD4+ memory T cells, other infected cells include macrophages,
dendrites, microglia, astrocytes, and hematopoietic progenitors. Theses infected cells continue
to release viral particles if therapy is stopped. (Pg 314)
ANSWERS
Question 1.
What are cytokines?
ANSWER
Growth factor, also called cytokines, stimulate an increase in cell mass or cell growth by
promoting the synthesis of proteins and other macromolecules and inhibiting their
degradation (p. 38)
Cytokines constitute a large family of small-molecular-weight soluble intracellular-signaling
molecules that are secreted, bind to a specific cell membrane receptors, and regulate innate or
adaptive immunity; either proinflammatory or anti-inflammatory. Majority of important
cytokines are classified as interleukins or interferons (p. 201)
Question 2.
Does estrogen affect lymphocytes?
ANSWER
Estrogens generally are associated with a depression of T-cell-dependent immune function and
an enhancement of B-cell functions. (pg. 338)
Question 3.
What is chemical signaling?
ANSWER
Primary means of cell-to-cell communication. 5 forms of signaling mediated by secreted
molecules: (1) Contact-dependent signaling requires cells to be in close membrane-membrane
contact; (2) Paracrine signaling- cells secrete local chemical mediators that are quickly
absorbed, destroyed, or immobilized; (3) Autocrine signaling- cells produce signals that they,
themselves, respond to (cancer cells); (4) Hormonal signaling involves specialized endocrine
cells that secrete chemicals called hormones (TSH). Hormones are released by one set of cells
and travel through the tissue and through the bloodstream to produce a response in other
sets of cells; (5) Neurohormonal signaling- hormones are released into the blood by
neurosecretory neurons. (p.19)
,Question 4.
What is active transport?
ANSWER
requires life, biologic activity, and the cell's expenditure of metabolic energy. Unlike passive
transport, active transport occurs across only living membranes that have to drive the flow
"uphill" by coupling it to an energy source (p. 28)
Question 5.
What happens to liver cells when a portion of the liver is removed?
ANSWER
When liver cells are compromised, new cells can regenerate from intrahepatic stem cells.
Compensatory hyperplasia is this adaptive mechanism that enables certain organs to
regenerate. If part of the liver is removed it leads to hyperplasia of the remaining
cells(hepatocytes) to compensate for the loss. Even if 70% of the liver is removed it only takes 2
weeks for complete regeneration. Hepatocytes usually live approximately a year or more, and
through a very slow rate of cell division they renew themselves. If large number of hepatocytes
are lost due
to surgery or injury; a burst of rapid cell division occurs from the surviving hepatocytes to
replace the lost tissue. (p49)
Question 6.
What is the process of repair after tissue damage?
ANSWER
Occurs in 3 phases and leads to either regeneration (complete return to normal structure and
function) or repair (replacement of destroyed tissue with scar tissue and results in loss of
function) (pg. 212)
Phase I - Inflammation
Inflammatory phase - "coagulation and infiltration of cells that participate in wound healing"
Debridement - by fibrinolytic enzymes, remaining debris drained away by blood vessels and
lymphatics.
Phase II - Proliferation and New tissue formation (Reconstruction) "Epithelization includes
formation of granulation tissue, inward migration of fibroblasts, and the beginning of collagen
synthesis and secretion. Granulation issue becomes scar tissue, contraction begins, and
differentiation begins." (pg. 212, 213)
Phase III - Maturation Phase
tissue regeneration and wound contraction continue. Capillaries disappear from scar tissue.
(pg. 213, 214)
, Question 7.
Which hormone helps to explain the mood cycles, anxiety, and eating disorders in women?
ANSWER
Estrogen (pg. 336)
Question 8.
After sexual transmission of HIV, a person can be infected yet seronegative for how long?
ANSWER
Seronegative = without antibodies; Antibodies can be detected 18-90 days post infection
Question 9.
Know about the effects of fetal alcohol syndrome on infants.
ANSWER
Diagnosis of FAS requires all three facial abnormalities: short palpebral fissure lengths, smooth
philtrum and thin upper lip. FAS may have abnormal facial features, growth problems, CNS
problems, issues with learning, memory, attention, vision, hearing. Pg 70
Question 10.
Where do lipids accumulate?
ANSWER
Although lipids sometimes accumulate in heart and kidney cells, the most common site of
intracellular lipid accumulation, or fatty change, is liver cells. Pg 84
Question 11.
What acts as
a reservoir in which HIV can be relatively protected from antiviral drugs?
ANSWER
Antiviral drugs do not cure HIV because the infected cells act as a reservoir.
The main infected cell is the CD4+ memory T cells, other infected cells include macrophages,
dendrites, microglia, astrocytes, and hematopoietic progenitors. Theses infected cells continue
to release viral particles if therapy is stopped. (Pg 314)
