module 3 - cell membrane structure

Question 1

cell membranes act as a ??

Answer 1

selective barriers

Question 2

what is a living cell

Answer 2

self-reproducing system of molecules held inside a container (plasma membrane)

Question 3

what is a plasma membrane

Answer 3

thin fatty acid studded with proteins and coated with carbs

Question 4

what is the function of a plasma membrane

Answer 4

receiving info, import and export small molecules, movement and expansion

Question 5

what are cell membranes composed of?

Answer 5

lipids and proteins

Question 6

what are phospholipids

Answer 6

liquid molecule and major lipid component

Question 7

phospholipids have a ??? and 2 ????

Answer 7

hydrophilic head and 2 hydrophobic tails

Question 8

what is the most common phospholipid

Answer 8

phosphatidylcholine

Question 9

hydrocarbon tail with no double bond is called

Answer 9

saturated

Question 10

hydrocarbon tail with double bond is called

Answer 10

unsaturated

Question 11

how is cell membrane transported by??

Answer 11

process of vesicle budding and fusing

Question 12

how do membranes retain their orientation?

Answer 12

during transfer between cell compartments

Question 13

membrane lipids are all?

Answer 13

amphipathic (molecules with both hydrophilic and hydrophobic parts)

Question 14

triacylglycerol is entirely?

Answer 14

hydrophobic

Question 15

phospholipid bilayers form

Answer 15

sealed compartments

Question 16

hydrophobic heads face?

Answer 16

water on both surfaces

Question 17

hydrophobic tails are all shielded from

Answer 17

water

Question 18

lipid bilayer is a flexible

Answer 18

2D fluid

Question 19

which are more fluid?

Answer 19

lipid bilayers with unsaturated hydrocarbon tails and ones with shorter fatty acids

Question 20

new membrane is synthesized in the??

Answer 20

ER (modified in Golgi)

Question 21

asymmetry is preserved during?

Answer 21

membrane transfer

Question 22

what are distributed asymmetrically?

Answer 22

phospholipids and glycolipids

Question 23

glycolipids are located in

Answer 23

plasma membrane

Question 24

what are the 5 plasma membrane proteins?

Answer 24

1. transporters
2. ion channels
3. anchors
4. receptors
5. enzymes

Question 25

what is cell membrane made up of

Answer 25

mosaic

Question 26

2 general types of membrane protein?

Answer 26

integral and peripheral

Question 27

integral protein?

Answer 27

extend through lipid bilayer (detergents)

Question 28

hydrophilic R groups interact with

Answer 28

aqueous environments

Question 29

hydrophobic R groups interact with

Answer 29

hydrophobic core of membrane

Question 30

transmembrane protein

Answer 30

integral protein that extends all the way through phospholipid bilayer (helix)

Question 31

how are amino acids localized?

Answer 31

polarity

Question 32

non polar amino acids are

Answer 32

hydrophobic

Question 33

polar amino acids are

Answer 33

hydrophilic

Question 34

where are non polar amino acids located

Answer 34

lipid bilayer

Question 35

where are polar amino acids located

Answer 35

internally and face aqueous solutions

Question 36

plasma membrane can move ??

Answer 36

laterally in lipid bilayer

Question 37

cell context is what

Answer 37

support for cell membrane (proteins)

Question 38

cell surface is coated with?

Answer 38

carbs (sugar coating)

Question 39

what does cell surface allow?

Answer 39

cell adhesion and allow neutrophils migrate at sites of infection

Question 40

cell can restrict movement of its ??

Answer 40

membrane proteins

Question 41

3 types of cell junctions?

Answer 41

1. desmosomal adhesion 2. tight junctions 3. gap junctions

Question 42

desmosomal adhesion

Answer 42

localized spot-like adhesions

Question 43

tight junctions

Answer 43

protein complex between 2 cells creates a seal to prevent leakage

Question 44

gap junctions

Answer 44

intracellular flow of ions and molecules between cytoplasms