CMB Lecture 3

Question 1

Bilayer is __ thick

Answer 1

8nm

Question 2

More proteins in _ layer

Answer 2

cytolpasmic

Question 3

Proteins that span hydrophobic regions are called

Answer 3

Amphipathic protein, both hydrophobic/hydrophillic

Question 4

Types of membrane transport:

Answer 4

Passive, Active, Exocytosis, Endocytosis,

Question 5

Unsaturated hydrocarbons will ____

Answer 5

bend, making the membrane fluid. This pushes away neighboring lipids, cannot solidify, helps retain fluidity in low temps.

Question 6

Cell-cell recognition:

Answer 6

Done by glycoproteins with carbohydrates

Question 7

Attachment to the cytoskeleton and ECM

Answer 7

Done by glycoprotein

Question 8

Types of junctions in animal tissues:

Answer 8

Tight junctions, Desmosome, Gap junction

Question 9

Cell junction in plant tissues

Answer 9

Plasmodesmata

Question 10

Tight junction functions:

Answer 10

Prevent fluid from moving across layer of cells, water tight

Question 11

Desmosome functions:

Answer 11

Anchoring 2 cells together tightly, Holds muscle cells together

Question 12

Gap junction:

Answer 12

Made up of connexin proteins, forms cylinder enabling communication between cells, only allows small ions, sugars ,AA through channel

Question 13

Plasmodesmata

Answer 13

Allow small proteins and n.a. between cells

Question 14

Passive transport of small molecules types:

Answer 14

Diffusion, facilitated diffusion

Question 15

Active transport:

Answer 15

Na/K+ pump

Question 16

Passive membrane transport moves energy requirements?

Answer 16

Spontaneous, no energy expenditure by cell required, moves from high conc. to low conc.

Question 17

Which molecules can diffuse with no protein?

Answer 17

Small non polar molecules (O2) and small uncharged polar molecules (CO2)

Question 18

Faciliated diffusion: which molecules can move passively through membrane when assisted by transport membranes?

Answer 18

Hydrophillic molecules.

Question 19

Which protein open and closes for diffusion?

Answer 19

Carrier protein

Question 20

What is active membrane transport?

Answer 20

Move against the conc gradient, usually reuqires ATP, all carrier protein eg/K pump

Question 21

Features of membrane transport proteins (x4)

Answer 21

Provides selectivity, can increase rate of transport, continuously recycled, however, rate of transport is limited by number of proteins.

Question 22

How does transport of large molecules across cell membrane occur?

Answer 22

Exocytosis, and endocytosis

Question 23

List the types of endocytosis

Answer 23

Phagocytosis, pinocytosis, and receptor mediated endocytosis.