NU 545 Patho Unit 1 STUDY GUIDE
assured success 100%
NU 545 Patho Unit 1 STUDY GUIDE
assured success 100%
What is metabolic absorption? (p.2) - ANSWER-• 1 of 8 cellular functions of eukaryote
cell
• Chief function is to take in & use nutrients or other substances from surroundings
• Ex: kidney (fluid absorption and synthesize proteins) and Intestinal epithelial cells (fluid
absorption/protein enzyme synthesis)
What uses oxygen to remove hydrogen atoms in an oxidative reaction? (p.8) -
ANSWER-• Peroxisomes contain enzymes that use O2 to remove H+ in oxidative
reactions that produces hydrogen peroxide which is then used by catalase to further
oxidize other substances like: phenols, formic acid, formaldehyde, and alcohol
During cell injury what is released that is capable of cellular autodigestion? (p. 8) -
ANSWER-• Lysosomal enzymes (hydrolases), or the digestive enzymes within the
lysosome
• Autolysosomes, or autophagosomes
Where is the genetic info contained in the cell? (p. 2) - ANSWER-Nucleus, specifically
the nucleolus
Cell membranes contain which major chemical components? (p. 12) - ANSWER-Lipids
& Proteins in a complex lipid bilayer
What allows potassium to diffuse in and out of cells? (p. 31-32) - ANSWER-• The Na+-
K+-ATP pump. Uses direct energy of ATP; found in excitable tissues (muscles/nerves)
& also in kidneys & salivary glands. Involves the movement of Na+ & K+ against a
concentration gradient.
• Protein enzyme ATPase allows potassium to move in and out of the cell.
• Mediated transport = channel protein through which ions can diffuse (K+ leak
channel).
How is a cell protected from injury? (p.12) - ANSWER-• Plasma membrane - Acts as a
barrier to toxic molecules, macromolecules, & foreign organisms/cells.
• Exists in a state of change & modulation. Alternates receptor numbers & patterns.
• Gating protects cells from release of Ca from injured cells by sealing off or decreasing
permeability at junctional complexes.
In cirrhosis, what does cholesterol have to do with the erythrocytes? (p.68) - ANSWER-•
Associated with chemical changes that result in structural & metabolic abnormalities of
the erythrocyte membrane leading to cell shape changes & hemolytic anemia.
,NU 545 Patho Unit 1 STUDY GUIDE
assured success 100%
• Increase in unesterified serum cholesterol owing to lecithin cholesterol acyl transferase
(LCAT) deficiency in cirrhosis leads to expansion of the lipid bilayer & macrocytosis
without megaloblastic changes in precursors. Substitutions of phosphatidyl choline (PC)
moieties in the erythrocyte lipid bilayer lead to echinocytes (disaturated PC) or to
stomatocytes (diunsaturated PC). In some patients, high density lipoprotein (HDL)
abnormalities lead to erythrocyte surface changes causing rapid formation of
echinocytes. (Ann Clin Lab Sci. 1990 May-Jun;20(3):169-74.Mechanisms of hemolysis
in liver disease.Morse EE1.
Department of Laboratory Medicine, University of Connecticut School of Medicine,
Farmington 06032)
• Alters fluidity & function of cell membrane as well as intercellular transport
What is platelet-derived growth factor? (p.39) - ANSWER-Stimulates production of
connective tissue cells & neuroglial cells
What is cell communication? How does it occur? (p.20) - ANSWER-• Required for
homeostasis, regulate cellular growth/division & development/organization into tissues,
& coordinate cellular function.
• Occurs in 3 ways:
-via protein channels & gap junctions that directly coordinate activities of adjacent cells
(must be touching)
-via plasma membrane-based signaling molecules (receptors) that affect the cell itself
& cells that come in direct contact
-via chemical signals that must enter the distant cells to affect the receptors inside of
the distant cell (the most common means of communication).
• Primary modes of intercellular signaling are hormonal, neurohormonal, paracrine,
contact-dependent, & neurotransmitters. There is also Autocrine signaling where the
cell signals itself.
What is chemical signaling? (p.20) - ANSWER-Involves the secretion of chemicals,
such as hormones, neurohormones, paracrine, autocrine, and neurotransmitters.
Chemical signaling may occur through the bloodstream or in small discrete spaces
How is glucose transported from the blood to the cell? (p. 33) - ANSWER-Passive
protein channels.
Passive mediated transport or facilitated diffusion moves the glucose via a uniport
mechanism into the cell. When all glucose-specific receptors are occupied, the transport
system is saturated and operating at maximal capacity. Direction of movement is the
same as passive simple diffusion-down the concentration gradient, from an area of high
concentration to low concentration until equilibrium is achieved.
Understand the transportation of potassium and sodium across plasma membranes. (p.
29-32) - ANSWER-• The Na+ K+ antiport (opposite directions) system uses direct
energy of ATP to move cations.
, NU 545 Patho Unit 1 STUDY GUIDE
assured success 100%
• ATPase is transporter protein.
• Concentration of ATPase in plasma membranes is directly related to Na+ K+ transport
activity.
• Process:
- 3 Na+ ions bind to Na-binding sites on carrier's inner face.
- ATP molecule produced by cell's mitochondria binds to carrier.
- Carrier changes shape, releases 3 Na+ ions to outside of cell, & attracts 2 K+ ions to
K-binding sites.
- Carrier returns to original shape, releasing 2 K+ ions & the leftover ATP molecule to
inside of cell.
- Carrier can now repeat cycle.
What is active transport? (p. 31-33) ch.1 - ANSWER-• The movement of a substance
across a membrane by a carrier protein. Requires metabolic energy (ATP) to move the
molecules against the concentration gradient.
• Active transport also occurs by endocytosis (vesicle formation), where substances are
engulfed by a segment of the plasma membrane, forming a vesicle that moves into the
cell.
What are cytokines? (p.38-39)
Or cytokinesis? (p.37) - ANSWER-• Cytokines are peptides that transmit signals
within/between cells to stimulate tissue growth & development.
Do all cells continue to replicate or divide? (p. 39) - ANSWER-• No, all types of cells
undergo mitosis during formation of the embryo, but adult cells including: nerve cells,
lens cells, & muscle cells, lose the ability to replicate.
• When a need arises for new cells, as in the repair of injured cells, previously non-
dividing cells must be rapidly triggered to reenter the cell cycle.
• Neurons are fixed at birth & are unable to be replaced.
When normal columnar ciliated epithelial cells of the bronchial lining are replaced by
stratified squamous cells, the process is called? (p. 54) - ANSWER-• Metaplasia: the
reversible replacement of one mature cell by another, sometimes less differentiated cell
type.
• However, lose protective ability, because new cells don't secrete mucus or have cilia.
• Bronchial metaplasia can be reversed if inducing stimulus is removed, such as
cigarette smoking.
What is the relationship between ischemia and ATP? (p. 55-57) - ANSWER-• When a
hypoxic injury occurs to myocardium, which causes an abrupt lack of contraction
(caused by quick decline in mitochondrial phosphorylation), causing insufficient ATP
production.
• Lack of ATP leads to increase in anaerobic metabolism, which generates ATP from
glycogen when there is insufficient oxygen.
