Brainscape's Knowledge GenomeTM

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


See full index

From Molecules to Cells > Lecture 15: ECM and plant cell wall > Flashcards

Lecture 15: ECM and plant cell wall Flashcards

1
Q

What is the role of the extracellular matrix in animal tissues?

A

The architectural basis
Controls mechanical properties

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

How does the ECM control mechanical properties of animal tissues?

A

Through its protein composition

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

What type of collagen is in connective tissue?

A

90% is collagen 1
The amount of collagen 1 correlates to tissue stiffness

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

What is the composition of bone?

A

Collagen 1 which are dark and light rings
Osteoblasts that deposit ECM in bone are black dots
Gaps are calcium phosphate

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

What is collagen made by in bone?

A

Osteoblasts

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

What is collagen made by in skin and tendons?

A

Fibroblasts

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

What are the four stages of collagen composition?

A
  1. Procollagen polypeptide chain
  2. Triple stranded helical procollagen molecule
  3. Collagen fibril
  4. Collagen fibres
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is procollagen?

A

Collagen is secreted as procollagen
It can’t form fibrils until its cleaved

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

What is the organisation of procollagen?

A

Cells deposit it in an oriented way
They rearrange fibres after secretion using integrins in focal contacts

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

What are the results of genetic conditions affecting the ECM?

A

Abnormally stretchy skin
Brittle bone disease
Skeletal abnormalities

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

What is the role of integrins?

A

Attach the cell’s cytoskeleton to ECM

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

What determines cytoskeleton linkage?

A

The type of cell

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

What type of cytoskeleton linkage is in migrating cells?

A

Focal adhesions

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

What type of cytoskeleton linkage is in epithelial monolayers?

A

Hemi desmosomes

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

How to fibroblasts attach to the ECM?

A

Using integrins in focal contacts

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

How do cells bind to collagen?

A

Using a linker protein

17
Q

What is the linker protein in focal adhesions?

A

Fibronectin

18
Q

What is the linker protein in the basal lamina?

A

Laminin

19
Q

In what ways do integrins change during animal cell mitosis?

A

They are phosphorylated
Weaken their grip on ECM

20
Q

What is the role of the spaces in between collagen?

A

Filled by gels of polysaccharide and protein
Resist compression

21
Q

What are GAGs?

A

Large negative polysaccharides
Hydrophilic

22
Q

What are proteoglycans?

A

Extracellular proteins with covalently linked GAGs

23
Q

What is the process of proteoglycan synthesis?

A
  1. Protein component made in ER
  2. Glycosylation starts
  3. Glycosylation completed in golgi
  4. Delivered to plasma membrane by constitutive secretion
24
Q

What is cartilage?

A

Tough and resists compression
GAGs generate swelling pressure
Pressure resisted by collagen fibres

25
Q

What is hyalyronan?

A

Made of carbohydrate and no protein

26
Q

Where does hyaluronan synthesis happen?

A

Plasma membrane
Extruded into extracellular space

27
Q

What are the properties of the plant ECM?

A

Tough external walls for strength
Cell wall resists turgor pressure
Resists compression and tension
Long fibres oriented along stress lines

28
Q

What are the properties of the primary cell wall?

A

Laid down first
Relatively thin
Allows the cell to grow

29
Q

What are the properties of the secondary cell wall?

A

Composition controlled by cell to determine its properties
Hard in wood and flexible in leaves

30
Q

What are the purpose of cellulose fibres in the plant cell wall?

A

Tensile strength

31
Q

What is the structure of cellulose fibres?

A

Polysaccharide of D glucose
Long fibres with 16 strands
Held together with H bonds

32
Q

What is the arrangement of cellulose fibres?

A

Interwoven with other polysaccharides

33
Q

What is the role of pectin?

A

Sticks neighbouring cells together
Fills spaces and resists compression

34
Q

What is determined by the organisation of cellulose fibres?

A

The axis of cell growth
Tissue structure

35
Q

What is the process of synthesis of cellulose fibres?

A
  1. Cellulose synthase made at ER
  2. Transported by golgi to PM to synthesis cellulose
36
Q

What drives the movement of cellulose?

A

Cellulose synthesis

37
Q

What is the process of cellulose deposition in the plant cell wall?

A
  1. Cellulose fibrils synthesised and extruded through PM by cellulose synthase
  2. Microtubules in cell determine orientation of deposition outside of cell

From Molecules to Cells (23 decks)

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