Lecture 1 Flashcards
Margination of chromatin is an _____ change which usually occurs in response to major pathology or exposure to toxins and is indicative of _____.
Margination is an IRREVERSIBLE change which occurs in response to major pathology or exposure to toxins and is indicative of NECROSIS
Nucleolus is the site of _____ biogenesis and forms following mitosis.
Site of RIBOSOME bigenesis
The size, number, and organization of nucleoli is directly proportional to the rate of ______ biogenesis.
Proportional to the rate of RIBOSOME bigenesis
The nucleolus has 3 regions:
- _____ center
- Dense _____ component (middle)
- _____ component
- FIBRILLAR center
- Dense FIBRILLAR component (middle)
- GRANULAR component
Fibrillar center contains __RNA and proteins needed for ribosomal gene transcription.
Fibrillar center contains rRNA and proteins needed for ribosomal gene transcription.
During times of active protein synthesis, move toward _____ of nucleus –> facilitates movement of proteins from nucleus into cytoplasm through nuclear _____. When protein synth decreases, the nucleoli regress.
Move toward MARGINS of nucleus –> facilitates movement of proteins from nucleus into cytoplasm through nuclear PORES.
Nucleoli can respond to stress in two different ways:
- Hypertrophy, resultant from ______ hypertrophy or _____ infarction.
- Disruption, resultant from inhibition of _____ from agents such as _____D.
- Hypertrophy, resultant from CARDIAC hypertrophy or MYOCARDIAL infarction.
- Disruption, resultant from inhibition of TRANSCRIPTION from agents such as ACTINOMYCIN D
Viral infections can disrupt nucleolar activity because some of their proteins have nucleolar localization sequences. ____ protein of HIV interacts with nucleolar protein ____, causing rearrangement of nucleolar proteins. This can affect cell cycling.
REV protein of HIV interacts with B23, causing rearrangement of nucleolar proteins. This may affect cell cycling
There is a link between the nucleolus and neurodegenerative diseases such as _____ and _____. Decreased expression of ____RNA genes and nucleolar dysfunction may lead to neurodegeneration.
Diseases such as ALZHEIMER’S and HUNTINGTON’S. Decreased expression of rRNA genes and nucleolar dysfunction may lead to neurodegeneration.
In _____ lung disorder, Alveolar epithelial cells are replaced with cuboidal epithelial with many intracellular tubules and vesicles (which are derived from invaginations of nuclear membrane.)
In FIBROTIC lung disorder
Pathological changes in the nucleus may also include presence of ______ inclusions, which are indicative of a huge amount of protein in nucleus, sometimes resulting from viral infection. ____ particles themselves may also be found in the nucleus.
CRYSTALLINE inclusions. VIRAL particles themselves may also be found in the nucleus.
There are four regions of the mitochondria:
- Outer membrane - which contains transport proteins and proteins involved in mitochondrial _____ synthesis.
- Intermembrane space - which contains enzymes that use _____ passing out of the matrix to _____ other nucleotides.
- Inner membrane - which contains enzymes of the _____ chain
- Matrix - which contains mitochondrial _____, ribosomes, tRNA, enzymes needed for oxidation of ____ and fatty acids as well as the CAC.
- Outer membrane - contains transport proteins and proteins involved in mitochondrial LIPID synth.
- Intermembrane space - contains enzymes that use ATP passing out of matrix to PHOSPHORYLATE other nucleotides.
- Inner membrane - contains enzymes of the RESPIRATION chain
- Matrix - contains mitochondrial DNA, ribosomes, tRNA, enzymes needed for oxidation of PYRUVATE and fatty acids as well as enzymes for the CAC.
Dense granules in the mito matrix indicates presence of divalent _____.
CATIONS
In cells with high levels of metabolic activity, mito cristae take on a _____ arrangement.
CONCENTRIC
In hypertrophied myocardium, mito cristae can take on a ____-____ form, which confers the same benefits as a concentric arrangement –> increased surface area and packing for increased metabolic activity.
ZIG-ZAG
In tissues that transport large amounts of water and divalent cations, _____ granules can increase in size and number.
DENSE
In almost every type of tissue damage, mito will _____, indicating influx of water and solutes. This can also occur with viral infection, and cristae become ______.
Mito will SWELL.
Cristae become MARGINALIZED.
Cells treated with toxic agents can exhibit ring and ____-shaped mitos
Ring and CUP-shaped mitos
____ droplets can accumulate in mitos with increased activity of the ____ membrane, and may indicate the mito is dying out.
LIPID droplets can accumulate with increased activity of OUTER membrane.
____ inclusions are typically found in patients with anemia.
IRON
Unlinke nuclear DNA, mtDNA only has one mechanism for repair: _____.
BER (base excision repair.)
Acute myeloid leukemia (AML) cells have greater numbers of mitos and produce more ROS. These ROS can increase the oxidative stress experienced by neighboring ____ ____ stromal cells. This stimulates formation of _____ nanotubules that connect AML cells to ____ ____ stromal cells at which point mitos from ____ ____ stromal cells migrate to AML cells.
These ROS can increase the oxidative stress experienced by neighboring BONE MARROW stromal cells. This stimulates formation of TUNNELING nanotubules from AML cells that connect them to BONE MARROW stromal cells at which point mitos from BONE MARROW stromal cells migrate to AML cells.
