Assessment and Study Guide for University-
Level Learners
1. WHAT IS METABOLIC ABSORPTION? (p. 2, 7th ed)
Metabolic absorption- cells taking in and using nutrients and
other substances from their surroundings.
For instance, cells of the intestine and the kidneys are
specialized to carry out absorption. Cells of the kidney tubules
reabsorb fluids and synthesize proteins while intestinal
epithelial cells absorb fluid and synthesize protein enzymes.
2. WHAT USES OXYGEN TO REMOVE HYDROGEN ATOMS IN AN
OXIDATIVE REACTION? (p. 8, 7th ed)
Peroxisomes (microbodies which are membrane-bound
organelles that contain several oxidative enzymes) contain
enzymes that use oxygen to remove hydrogen atoms from
specific substrates in an oxidative reaction that produces
hydrogen peroxide (H2O2).
[FYI: Peroxisomes also play a special role in nerve cell
myelination and detoxifying various wastes, so impairment of
them can lead to disease.]
3.DURING CELL INJURY, WHAT IS RELEASED THAT IS CAPABLE OF
CELLULAR
AUTODIGESTION? (p. 7 & 64, 7th ed)
Lysosomes are sack like structures that originate from the Golgi
complex that contain more than 40 digestive enzymes. They
function as the intracellular digestive system and are capable of
digesting most cellular constituents completely to their basic
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,Unit 1 SG
components. Disruption of the lysosomal membrane by various
treatments or cellular injury leads to a release of the lysosomal
enzymes or hydrolases causing cellular self-digestion
(autodigestion).
4. WHERE IS GENETIC INFO CONTAINED IN THE CELL? (p. 2, 7th ed)
The nucleus contains the nucleolus, a small dense structure
composed largely of RNA; most of the cellular DNA; and the DNA-
binding proteins, the histones, that regulate its activity.
The primary functions of the nucleus are cell division and
control of genetic information. (Also replication and repair of
DNA and the transcription of the information stored in DNA.)
(p.2)
5. CELL MEMBRANES CONTAIN WHICH MAJOR CHEMICAL
COMPONENTS? (p.
11-12, 7th ed)
Lipids and proteins
6. WHAT ALLOWS POTASSIUM TO DIFFUSE IN AND OUT OF
CELLS? (p. 32)
The sodium – potassium pump with ATP active transport/
ATPase (Adenosine Triphosphatase) The resting plasma
membrane is more permeable to sodium- potassium pump
7. HOW IS THE CELL PROTECTED FROM INJURY?
The cell membrane and lipid bilayer. It controls what comes in
and out of the cell, gives structure
8. IN CIRRHOSIS, WHAT DOES CHOLESTEROL HAVE TO DO WITH
THE ERYTHROCYTES?
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,Unit 1 SG
Cholesterol content of the red blood cell's plasma membrane
incrneases, causing a decrease in membrane fluidity and affects
the cell's ability to transport oxygen
9. WHAT IS PLATELET-DERIVED GROWTH FACTOR? (p.39)
PDGF stimulates the production of connective tissue cells and
neuroglial cells
10. WHAT IS CELL COMMUNICATION? HOW DOES IT OCCUR? (p.
20) Maintains homeostasis and regulates growth, division,
developments, and organization into tissues; coordinates
functions. How does it occur? 3 ways: 1. Display signaling
molecules (receptors) that affect the cell itself and other cells in
direct contact. 2. Affect receptor proteins inside the target cell
(enter the cell). 3. Protein channels (gap junctions) coordinate
activities of adjacent cells.
11. WHAT IS CHEMICAL SIGNALING? (p. 21) Communication at a
distance, hormonal, neurohormonal, paracrine, autocrine, and
neurotransmitter
Paracrine signaling: secrete mediators that are absorbed or
destroyed. Involves different cell types.
Autocrine signaling: produce signals that they themselves
respond to (i.e. Cancer). Hormonal signaling: endocrine cells
secrete hormones to produce response in another set of cells (i.e.
thyroid stimulating hormone).
Neurohormonal signaling: hormones released by neurosecretory
neurons
12. HOW IS GLUCOSE TRANSPORTED FROM THE BLOOD TO THE
CELL? (p.32,
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, Unit 1 SG
33 & 144)
Passive protein channel: passive mediated (facilitated diffusion)
using protein transporter down concentration gradient with no
energy expenditure. Happens by a uniport transporter. It
demonstrates saturation kinetics, transport system is saturated
when all glucose specific receptors are occupied
13.UNDERSTAND THE TRANSPORTATION OF POTASSIUM AND
SODIUM
ACROSS PLASMA MEMBRANES. (p. 32)
Active transport potassium and sodium use direct energy of ATP
in plasma membrane; for every 3 molecules of Na that move out,
2 K+ molecules enter. This causes the inside of the cell to be
more negative than the outside. The 3 Na bind to carrier and at
the same time ATP binds to the carrier. ATP breaks, the carrier
changes shape and releases Na. The carrier attracts 2 K, the
carrier returns to original shape and releases K and ATP remnant.
14.WHAT IS ACTIVE TRANSPORT? (p. 32)
Movement of substance across a membrane by carrier protein
that requires expenditure of energy for activation. Only occurs
across living membranes. Receptors must recognize and bind
with the substance to be transported
15. WHAT ARE CYTOKINES? (p. 38, 7th ed)
They are growth factors (peptides) that transmit signals within
and between cells. They have a major role in the regulation of
tissue growth and development.
16. DO ALL CELLS CONTINUE TO REPLICATE AND DIVIDE?
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