Brainscape's Knowledge GenomeTM

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


See full index

Biochemestry > Cellular > Flashcards

Cellular Flashcards

1
Q

Defining characteristics of Ehlers Danlos syndrome (type 1 and 2)

A
  1. Joint hypermobility
  2. Hyperextensible, fragile skin
  3. Most common cause of EDS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Defining characteristics of osteogenesis imperfecta

A
  1. Spontaneous fractures
  2. Bone and tooth malformation
  3. Blue sclerae
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Impairment in osteogenesis imperfecta

A

Mutation in type 1 collagen

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

Impairment in scurvy

A

Lack of vitamin C impairs collagen hydroxylation

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

Name the steps in collagen synthesis

A
  1. Synthesis
  2. Hydroxylation of proline and lysine
  3. Glycosylation of pro-a-chain hydroxyproline residues and formation of procollagen via hydrogen and disulfide bonds (triple helix!)
  4. Exocytosis of procollagen
  5. Proteolytic processing (cleavage of disulfide-rich terminal regions leads to insoluble tropocollagen)
  6. Cross linking (lysine-hydroxylysine by copper containing lysyl oxidase)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Pathogenesis of Menkes disease

A

Defective ATP7A protein (Menkes protein), which is a copper transporter, results in impaired copper absorption and transport - Therefore, enzymes that use copper will function inapropiately

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

Affected enzymes in Menkes disease

A
  1. Lysyl oxidase (crosslinking of collagen fibers) - leads to “kinky”, brittle hair
  2. Cytochrome C oxidase (neurologic abnormalities)
  3. Tyrosinase (hypopigmentation)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Hereditary mode of transmission of Menkes disease

A

X-linked recessive

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

Name the 2 main divisions of the M phase of the cell cycle

A
  1. Mitosis

2. Cytokinesis

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

Name the 5 subdivision of mitosis

A
  1. Prophase
  2. Prometaphase
  3. Metaphase
  4. Anaphase
  5. Telophase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Function of p53 protein

A

Induces p21, which in turn inhibits CDKs, leading to hypophosphorylation of Rb (activating it) and inhibition of G1-S progression

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

Function of the smooth endoplasmic reticulum

A

Steroid synthesis and detoxification of drugs and poisons

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

Cells that are rich in SER

A
  • Liver hepatocytes

* Steroid hormone-producing cells of the adrenal cortex and gonads

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

Cdk that phosphorylates Rb and promotes progress to S phase

A

Cdk4

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

Protein modification done on the Golgi apparatus to proteins that are transported to lysosomes

A

Addition of mannose-6-phosphate

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

Deficient/defective enzyme in I-cell disease

A

N-acetylglucosaminyl-1-phosphotransferase

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

Pathogenesis of I-cell disease

A

Failure of the Golgi to phosphorylate mannose residues leads to a decrease in mannose-6-phosphate, therefore proteins are secreted extracellularly rather than delivered to lysosomes

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

Signs and symptoms of I-cell disease

A
  • Corse facial features
  • Clouded corneas
  • Restricted joint movement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Characteristic laboratory finding in I-cell disease

A

High plasma levels of lysosomal proteins

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

Abundant, cytosolic protein that traffics proteins from the ribosome to the RER

A

Signal recognition particle (SRP)

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

Absent or dysfunctional signal recognition particle (SRP) leads to…

A

Accumulation of proteins in the cytosol

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

Traffic direction of COP1 proteins

A
  • Golgi to Golgi (retrograde)

* cis-Golgi to ER

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

Traffic direction of COP2 proteins

A

*ER to cis-Golgi (anterograde)

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

Traffic direction of Clathrin

A
  • trans-Golgi to lysosomes

* Plasma membrane to endosomes (receptor-mediated endocytosis)

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

Protein modification done on the Golgi apparatus to proteins that are destined for secretion

A

Adding of sialic acid

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

Function of the peroxisome

A

Catabolism of:

  • Very-long-chain fatty acids (beta oxidation)
  • Branched-chain fatty acids
  • Aminoacids
  • Ethanol

And synthesis of PLASMALOGENS, important phospholipids in myelin

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

Signs and symptoms of Zellweger syndrome (peroxisomal disease)

A
  • Hypotonia
  • Seizures
  • Hepatomegaly
  • Early death
28
Q

Signs and symptoms of Refsum disease (peroxisomal disease)

A
  • Scaly skin
  • Ataxia
  • Cataracts/night blindness
  • Shortening of the 4th toe
  • Epiphyseal dysplasia
29
Q

Actin and microvilli are examples of what type of cytoskeletsl filaments

A

Microfilaments

30
Q

Cilia, flagella, the mitotic spindle, and the centrioles are examples of what type of cytoskeletal filament

A

Microtubules

31
Q

Identified cell type by staining GFAP intermediate filaments

A

Neuroglia (eg, astrocytes, Schwann cells, oligodendrocytes)

*Identifies astrocytomas and glioblastomas

32
Q

Identified cell type staining Vimentin intermediate filaments

A

Mesenchymal tissue (eg, fibroblasts, endothelial cells, macrophages)

33
Q

Identified cell type staining Desmin intermediate filaments

A

Muscle

34
Q

Direction of dynein movement in microtubules

A

Retrograde to microtubules (towards the negative end, Negative Near Nucleus)

*Di NO (negativo)

35
Q

Direction of movement of kinesin in microtubules

A

Anterograde to microtubules (towards the positive end, Positive Points to Periphery)

36
Q

Drugs that act on microtubules

A

“Microtubules Get Constructed Very Poorly”

  • Mebendazole
  • Griseofulvin
  • Colchicine
  • Vincristine/Vinblastine
  • Paclitaxel
37
Q

Microtubular structure of cilia

A

9 doublet + 2 singlet arrangement of microtubules

*Basal body consists of 9 microtubule triplets

38
Q

Pathogenesis of Kartagener syndrome

A

Immotile cilia due to a dynein arm defect

39
Q

Signs and symptoms of Kartagener syndrome

A
  • Decrease in fertility
  • Increased risk of ectopic pregnancy
  • Bronquiectasis
  • Recurrent sinusitis
  • Chronic ear infections
  • Conductive hearing loss
  • Situs inversus
40
Q

Number of Na and K molecules transported through the Na-K ATPase

A

For each ATP consumed, 3 Na go out (phosphorylated pump) and 2 K go in (dephosphorylated pump)

41
Q

Site of the Na-K ATPase that is inhibiten by ouabain

A

The K site (dephosphorylated state of the pump)

42
Q

Most common type of collagen

A

Type 1

43
Q

Structures with predominantly type 1 collagen

A
  • Bone
  • Skin
  • Tendon
  • Dentin
  • Fascia
  • Cornea
  • Late wound repair
44
Q

Structures with predominantly type 2 collagen

A
  • Cartilage (including hyaline)
  • Vitreous body
  • Nucleus pulposus
45
Q

Structures with predominantly type 3 collagen (reticulin)

A
  • Skin
  • Blood vessels
  • Uterus
  • Fetal tissue
  • GRANULATION TISSUE and KELOID FORMATION
46
Q

Structures with predominantly type 4 collagen

A
  • Basement membrane
  • Basal lamina
  • Lens
47
Q

Type of collagen found in the epiphyseal growth plate

A

Type 10

48
Q

Most abundant aminoacid in collagen

A

Glycine (1/3)

*Structure is Gly-X-Y, where X and Y are proline or lysine

49
Q

Cofactor required for hydroxylation of proline and lysine residues during collagen synthesis

A

Vitamin C

50
Q

Residue that gets glycosylated during the third step of collagen synthesis

A

Hydroxylysine residues

51
Q

Types of bonds that form procollagen (triple helix of 3 collagen alpha chains)

A

Hydrogen and disulfide bonds

52
Q

Collagen synthesis steps that take place in the RER

A
  1. Synthesis (translation of preprocollagen)
  2. Hydroxylation of proline and lysine
  3. Glycosylation of hydroxylysine residues
53
Q

Function of procollagen peptidase

A

Cleavage of procollagen C- and N- terminals (disulfide-rich) to form insoluble tropocollagen

54
Q

Cofactor required by lysyl oxidase to form covalent lysine-hydroxylysine cross-linkage

A

Copper

55
Q

Collagen synthesis steps that take place extracellularly

A
  1. Cleavage of procollagen

2. Cross-linkage

56
Q

Deficient/defective enzyme in Menkes disease

A

Lysyl oxidase

57
Q

Mutations in which genes can lead to osteogenesis imperfecta

A

COL1A1 (chromosome 17) and COL1A2 (chromosome 7)

58
Q

Decreased production of what type of collagen leads to osteogenesis imperfecta

A

Type 1 collagen

59
Q

Signs and symptoms of osteogenesis imperfecta

A

Patients can’t BITE

  • Bones = multiple fractures
  • I (eye) = blue sclerae
  • Teeth = dental imperfections
  • Ear = hearing loss
60
Q

Signs and symptoms of Ehlers-Danlos syndrome

A
  • Hyperextensible skin
  • Tendency to bleed
  • Hypermobile joints

Associated with joint dislocation, berry and aortic aneurysms, organ rupture

61
Q

Type of collagen mutated in classical Ehlers-Danlos syndrome

A

Type 5 collagen

62
Q

Main structural difference between collagen and elastin

A

Elastin is rich in NONHYDROXYLATED proline, lysine, and glycine residues

63
Q

Protein modification that gives elastin its elastic properties

A

Cross-linking

64
Q

Elastase, the enzyme that degrades elastin, is inhibited by what other enzyme

A

alpha1-antitrypsin

65
Q

Pathogenesis of Marfan syndrome

A

Autosomal dominant connective tissue disorder due to a mutation in the FBN1 gene on chromosome 15 that results in defective fibrillin

*Fibrillin forms a sheath around elastin

66
Q

Signs and symptoms of Marfan syndrome

A
  • Tall with long extremities
  • Pectus carinatum or excavatum
  • Hypermobile joints
  • Aracnodactyly
  • Cystic medial necrosis of the aorta
  • Aortic incompetence and dissecting aortic aneurysms
  • Floppy mitral valve
  • Subluxation of lenses (upward and temporally)
67
Q

Pathogenesis of achondroplasia

A

Missense mutation in the FGFR3 gene (chromosome 4) that leads to irreversible activation of fibroblast growth factor receptor 3, thereby inhibitin chondrocyte proliferation

Biochemestry (7 decks)

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