Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Histology > Block 1: Cell Organelles > Flashcards

Block 1: Cell Organelles Flashcards

1
Q

RER
s(x)
f(x)

A

s(x): parallel stacks of flattened cisternae
f(x): protein production (membrane associated proteins, proteins of membranous organelles, proteins secreted by exocytosis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

SER
s(x)
f(x)

A

s(x): lacks ribosomes; appears smooth and glandular; tubular cisternae
f(x): steroid hormone & phospholipid synthesis, Ca2+ sequestration, detoxification of potentially harmful moleculse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the function of smooth ER in synthesis of non-protein substrates

A

synthesis of steroid hormones and lipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the function of SER in catabolism and detoxification

A

SER enzymes, including those of the cytochrome P450 family and UDP glucoronosyltransferases, allow detoxification of potentially harmful exogenous molecules by turning them into water soluble metabolites that can be eliminated from the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the function of SER in muscle cells

A

sarcoplasmic reticulum

smooth ER is responsible for sequestration of Ca2+. this plays a role in rapid cellular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How does smooth ER function in cellular metabolism?

A

outer membrane of SER contains enzymes that participate in metabolic pathways, such as the release of glucose from glycogen in the liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Cis vs. Trans Face

A

cis face (convex): receiving face; receives COPII coated transport vesicles from the rough ER

trans face (concave): vesicles ready for exocytosis are produced here; retrograde movement of COPI coated proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Mitochondria
s(x)
f(x)

A

s(x): membrane bound, dotted w/ enzymes and proteins (ETC, ATP synthase)
inner and outer membrane, with inner membrane projecting in as cristae that increase surface area
f(x): ATP production, ox phos, CAC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the functional spaces of the mitochondria

A

matrix: gel; location of enzymes for CAC & fatty acid ox; also contains DNA, tRNA, rRNA, mRNA

intermembrane space: very H+ rich; movement of e- from matrix to IM space generates EC gradient used to power ATP synthase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

golgi apparatus
f(x)
s(x)
mechanism for f(x)

A

f(x): post translational modification of proteins, then packaging & directing them to their destinations
s(x): smooth cisternae
mechanism: budding vesicles shuttle newly synthesized proteins from one face to another face

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How can proteins be sorted in the TGN?

A

plasma membrane
secretory granules (vesicles)
lysosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Endosomes

stages

A

endosomes start as early endosomes immediately after receptor mediated endocytosis or pinocytosis. they can travel deep in the cell and become late endosomes, which receive lysosomal enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Lysosomes
s(x)
f(x)

A

s(x): membrane walled vesicles with hydrolytic enzymes and acidic pH
f(x): sites of intracellular digestion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the lysosomal stages

A

Primary: quiescent; not involved in digestion
Secondary: fused w/ a late endosome/phagosome
Residual Body: indigestible material that remains in vacuolar structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe heterophagy vs. autophagy

A

heterophagy: material from outside the cell is taken in via endocytosis, digested when a phagosome fuses w/ lysosome
autophagy: excess organelles or nonfunctional molecules are degraded this way. produces autophagosomes that fuse with lysosomes for digestion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Peroxisomes
s(x)
f(x)

A

s(x): membrane bound structures
f(x): B-oxidation of long chain FAs; decompose hydrogen peroxide into water & O2 via catalase; biosynthesis of plasmalogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Plasmalogen

A

membrane phospholipids in nerve and cardiac tissues that protect cells against singlet oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Proteasome
s(x)
f(x)

A

s(x): multi-protease complex
f(x): digestion of proteins targeted for destruction by ubiquination

ubiquinated proteins are incorrectly folded or in excess

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the main types of inclusions

A

lipid droplets
glycogen granules
pigment deposites (lipofuscin, melanin, hemosiderins)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Glycogen Granules

f(x)

A

glycogen stored in the cytosol and later undergoes glycogenolysis to form glucose for CAC use

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Lipid Droplets

f(x)

A

lipids stored as triglycerides that are catabolized into FA’s fed into the CAC for pyruvate formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Lipofuscin

A

yellow to brown pigment in long lived cells that are the indigestible remnants of lysosomal activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Hemosiderin

A

an iron storage complex found w/i cytop; indigestible residues of hemoglobin, related to RBC phagocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Lysosomal Storage Disorders
cause
result
presentation in children

A

cause: defects in one or more of the enzymes present in lysosomes.
result: indigestible material accumulate in residual bodies, and eventually those impair the function fo the cell
presentation: children normal at birth, eventually show slow growth, facial feature changes, limb movement restriction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Tay Sachs
enzyme affected
result

A

enzyme: GM2 gangliosidase
result: nervous system issues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How are polyribosomes formed?

A

individual ribosomes are held together by an mRNA strand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What types of proteins are made on cytoplasmic ribosomes? ER ribosomes?

A

cytoplasmic: for use within the cell
ER: secreted or stored; membrane associated proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

ER signal sequences

A

sequence on the 5’ end of proteins that allows them to get into the rough ER

29
Q

sickle cell anemia

A

a glutamine is exchanged for valine, causing the erythrocytes to become disfigured so they become sickle shaped, and their ability to transport oxygen is greatly reduced

30
Q

alpha1 antitrypsin deficiency

A

point mutation resulting in RER unable to export alpha1-antitrypsin, leading to emphysema and impaired liver function

31
Q

mitochondrial cytopathy syndromes
cause
result

A

cause: abnormal mitochondrial DNA
result: structural abnormalities of muscle and the nervous system as well as metabolic abnormalities from failure of ox phos

32
Q

Myoclonic Epilepsy w/ Ragged Red Fibers
cause
result

A

cause: aggregates of abnormal mitochondria
result: muscle weakness, ataxia, seizures, cardiac & respiratory failure.

33
Q

Describe the relationship b/w endosomes and lysosomes

A

lysosomal membranes and proteins are packaged in the trans golgi network and are delivered to late endosomes, forming endolysosomes. these then mature into lysosomes.

34
Q

Glycogenosis

disesase name
enzyme deficiency
metabolite buildup

A

name: pompe’s disease
enzyme: lysosomal glucosidase
metabolite: glycogen

35
Q

Sphingolipidosis (gaucher’s)
enzyme deficiency
metabolite buildup

A

enzyme: glucocerebrosidase
metabolite: glucocerebroside

36
Q

Sphingolipidosis (niemann pick)
enzyme deficiency
metabolite buildup

A

enzyme: sphingomyelinase
metabolite: sphingomyelin

37
Q

Mucopolysaccharidosis (I)
disease name
enzyme deficiency
metabolite buildup

A

name: MPS I H (hurler)
enzyme: alpha 1- iduronidase
metabolite: heparan and dermatan sulfate

38
Q

Mucopolysaccharidosis (II)
disease name
enzyme deficiency
metabolite

A

disease: MPS II ((hunter)
enzyme: 1-iduronosolfate sulfatase
metabolite: heparan and dermatan sulfate

39
Q

Adrenoleukodystrpohy

cause
effect

A

cause: defective integral protein needed to transport long chain fatty acids into the peroxisome for B oxidation
result: accumulation in body fluids disrupts myelin sheaths in nerve tissue, causing neurologic symptoms

40
Q

Zellweger Syndrome
cause
effect

A

cause: inability of peroxisomes to incorproate peroxisomal enzymes
result: inability of peroxisomes to perform B oxidation of long chain FA’s for plasmalogen synthesis, with plasmalogen being the most abundant phospholipid in myelin

41
Q

Microtubules
s(x)
f(x)
mechanism for f(x)

A

s(x): cylinders composed of tubulin (tubulin heterodimer subunits)
f(x); cell shape, development, and intracellular transport
mechanism: movement of intracellular organelles is generated by molecular motor proteins called dyneins and kinesins

42
Q

Kinesins vs Dyneins

A

kinesins: carry organelles away from MTOC, toward the plus end
dyneins: carry vesicles in opposite direction

43
Q

Colchicine
f(x)
use

A

f(x): binds to tubulin molecules and prevents their polymerization.
use: in gout patients to prevent neutrophil migration & decrease the ability to respond to urate crystal deposits

44
Q

F(x) of microtubules in cell division

A

tubulin polymerizes and depolymerizes to build spindles for chromosomes

45
Q

Microtubules form the basis of what cellular structures?

A

centrioles
primary cilia
cilia & flagella

46
Q

Centrioles
s(x)
f(x)

A

s(x): 9 sets of microtubule triplets

component of centrosomes; centrosome surrounds 2 centrioles

47
Q

Describe the parts of the nucleolus

A

fibrillar center (containing DNA sequences for rRNA)
fibrillar material: sites of active transcription
granular material: initial ribosomal assembly

48
Q

Nuclear Lamina
composition
f(x)
fate during mitosis

A

composition: lamin A and B
f(x): support matrix for the nucleus; important for DNA transcription and translation
fate: disassembles/reassembles

49
Q

Nuclear Envelope
s(x)
f(x)

A

s(x): inner and outer membranes w/ perinuclear cisternal space b/w; inner and outer membrane fuse at the nuclear pore
f(x): has openings called nuclear pores that allow for transport of protein, riboproteins and RNAs

50
Q

Nuclear Pore Complex
s(x)
f(x)
mechanism

A

s(x): made up of nucleoporins
f(x): transport of proteins, RNAs bidirectionally
mechanism: utilize energy derived locally from GTP, mediated by importins and exportins

51
Q

Centrosomes
s(x)
f(x)

A

s(x): a pair of centrioles

f(x): duplicate and move to opposite poles to become microtubule organizing centers of mitotic spindle

52
Q

Describe ribosomal subunit synthesis

A

rRNA molecules are processed in the nucleolus and associate w/ ribosomal proteins made in cytoplasm that help with assembly of the ribosomal subunit. the organized subunits are then exported back to the cytoplasm

53
Q

Microfilaments
s(x)
f(x)
mechanism

A

s(x): 2 intertwined F actin filaments concentrated beneath the cell membrane
f(x): contract and move cells, change cell shape
mechan

54
Q

Primary Cilia
s(x)
f(x)

A

s(x): non motile, short no central mcirotubules and lack dynein (9+0 arrangement)
f(x): non motile, act as receptors in kidney detecting flow

55
Q

Cilia and Flagella
s(x)
f(x

A

s(x): axenome arrangement (9+2)

f(x): motility

56
Q

primary ciliary dyskinesis
what is it?
results in

A

what: defects in organization of microtubules and associated proteins immobilizing cilia of respiratory epithelium and flagella of male repro
results in: chronic respiratory infections, sperm motility

57
Q

Example of actin filaments providing structure to cell membrane

A

ex: spectrin and ankyrin in RBCs

when there is a deficiency of spectrin, which actin binds to, then there’s a defective shape in RBCs

58
Q

Intermediate Filaments
f(x)
e(x)

A

f(x): anchored to desmosomes and hemidesmosomes; spread tensile forces evenly through a cell so single cells aren’t disrupted

e(x): nuclear lamins, vimentin in mesenchymal cells, cytokeratin in epithelial cells, desmin in muscle, glial fibrillary acidic proteins in astrocytic glial cells, neurofilaments in neurons

59
Q

Alzheimers is a result of

A

changes in neurofilaments within the brain tissues

60
Q

What’s the role of p53 in apoptosis?

A

p53 triggers apoptosis

61
Q 
Apoptosis 
size
uptake 
membrane 
organelles
A

size: cells shrink, only 1 cell affected
uptake: cell contents ingested by neighboring cells, no inflammatory response
membrane: membrane blebbing but integrity maintained; apoptic bodies formed
organelles: mitochondria release pro-apoptic protein; chromatin condensation and non random dNA degradation

62
Q 
Necrosis 
size 
uptake
membrane
organelles
A

size: cellular swelling, many cells affected
uptake: cell contents ingested by macrophages, causing significant inflammation
membrane: loss of membrane integrity, cell lysis occurs
organelles: organelle swelling & lysosome leakage; random DNA degradation

63
Q

autophagy vs apoptosis

A

autophagy: regulated cell turnover, allowing cells to turn over their contents by lysosomal degradation
apoptosis: programmed cell death to remove injured cells

64
Q

Describe the mitosis checkpoints

A

G1/S: start/restriction checkpoint
G2/M: ensures DNA replication is complete
metaphase spindle checkpoint ensures all chromosomes get segregated

65
Q

Cell cycle progression regulation

A

regulated by cyclins and cyclin dependent kinases that phosphorylate enzymes needed for phase spqecific functions

66
Q

Describe dynein arms normally and during motion

A

normal: inner and outer dynein arms are bound to microtubule A along its length
motion:

67
Q

Alexander Disease

characterized by

A

characterized by rosenthal fibers which are small masses of intermediate filament protein GFAP

associated w/ mutations of GFAP gene

68
Q

Mallory Bodies
s(x)
significance

A

s(x): intracytoplasmic inclusions composed of keratin intermediate filaments
significance: a prominent feature of alcoholic liver cirrhosis

69
Q

list the components of the nucleolus visible via EM

A

nucleolar organizer DNA
pars fibrosa: densely packed ribonucleoprotein fibers
pars granulosa: represents mature ribosomes

Histology (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions