Membrane Proteins

Question 1

2 primary types of membrane proteins

Answer 1

1) integral membrane proteins

2) peripheral proteins

Question 2

3 types of integral membrane proteins

Answer 2

1) transmembrane proteins
2) non-transmembrnae proteins
3) integrins

Question 3

2 subunits of an integrint

Answer 3

1) the portion that binds to the ECM

2) the portion that binds to microfilaments

Question 4

T/F: peripheral proteins are embedded in the phospholipid membrane

Answer 4

false. they rest on top of the membrane

Question 5

3 main components of the ECm

Answer 5

1) collagen
2) proteoglycan
3) fibronectin

Question 6

the ECM components binds to receptor proteins in the plasma membrane called ___

Answer 6

integrins

Question 7

describe the structure of a proteoglycan complex

Answer 7

• main core protein

2) carbohydrate branches

Question 8

3 general functions of a cytoskeleton

Answer 8

1) movement of cell or within the cell
2) structural support
3) maintenance of shape

Question 9

3 main types of filaments

Answer 9

1) microtubules
2) intermediate filaments
3) microfilaments

Question 10

Function of microtubules? What kind of cellular accessory is made by microtubules?

Answer 10

1) shapes and supports cell
2) guide MOVEMENt of organelle
3) separate chromosomes during cell division

controls the beating of CILIA

Question 11

describe the structure of a microfilament

Answer 11

a twisted double chain of actin subunits

Question 12

function of microfilament? What kind of cellular accessory is made by microfilaments?

Answer 12

• playes a structural role by bearing tension and resisting pullinf forces
• forms a 3D network inside the plasma membrane to help support the cell’s shape

makes up the CORE OF MICROVILLI

can contract a cell when paired with myosin

Question 13

microfilaments that function in cellular contractions contain the protein ___ in addition to actin.

Answer 13

myosin

Question 14

how is amoeboid movement accomplished?

Answer 14

localized contraction brought about by actin and myosin microfilaments. Amoeba’s use pseudopodia

Question 15

how to plants utilize microfilaments

Answer 15

cytoplasmic streaming

Question 16

what is cytoplasmic streaming

Answer 16

circular flow of cytoplasm wihtin cells in order to distrbribute materials in a timely manner.

Question 17

What drives cytoplasmic streaming in plants?

Answer 17

actin-myosin interactions

Question 18

____ are involved in cytokinesis, and ____ are involved in anaphase

Answer 18

MICROFILAMENTS are involved in cytokinesis, and MICROTUBULES are involved in anaphase (separate the chromosomes)

Question 19

Intermediate filaments are more ____ fixtures than the other two classes of cytoskeletons

Answer 19

PERMANENT. they support cell’s shape and fix organelles in place.

Question 20

role of fibronectin

Answer 20

part of ecm. binds with integrin (membrane) protein in the cell to anchor the cell into place