Chapter 2 (Pt. 1)

Question 1

what are the three main components in a cell membrane?

Answer 1

phospholipids
cholesterol
proteins

Question 2

what is the structure of a phospholipid? (3)

Answer 2

• glycerol backbone
• two fatty acid tails
• hydrophilic phosphate group

Question 3

what are the two classes of membrane proteins?

Answer 3

integral; peripheral

Question 4

which proteins are embedded in the core of the plasma membrane?

Answer 4

integral

Question 5

which proteins extend all the way through the membrane?

Answer 5

transmembrane

Question 6

role of transmembrane proteins? (2)

Answer 6

• signaling
• transport large, polar molecules across the cell membrane

Question 7

which proteins do not extend through the entire bilayer?

Answer 7

peripheral

Question 8

what are the three types of peripheral proteins?

Answer 8

receptors

adhesion

recognition

Question 9

recognition proteins, aka

Answer 9

glycoproteins

Question 10

ligands that bind to a receptor protein and activate its response are called:

Answer 10

agonists

Question 11

ligands that bind to a receptor and prevent it from activating are called:

Answer 11

antagonists

Question 12

agonists vs. antagonists?

Answer 12

AGONIST: bind to a receptor protein and activate its response

ANTAGONISTS: bind to a receptor and prevent it from activating

Question 13

what are the three main factors that affect membrane fluidity?

Answer 13

-temperature
-cholesterol
-phospholipid tail unsaturation

Question 14

which particles can travel directly across the phospholipid bilayer via simple diffusion?

Answer 14

small, uncharged, nonpolar

Question 15

saturated vs unsaturated fatty acids?

Answer 15

SATURATED: saturated with hydrogens at each carbon, straight.

UNSATURATED: double bonds, crooked.

Question 16

osmosis is a type of _______

Answer 16

simple diffusion

Question 17

give a definition and example of simple diffusion:

Answer 17

flow of substances down their concentration gradient; no energy.

osmosis.

Question 18

how do large, hydrophilic molecules travel across the bilayer?

Answer 18

facilitated transport by transmembrane proteins?

Question 19

what are the three main types (directions) of facilitated transport?

Answer 19

• uniport
• symport
• antiport

Question 20

what two classes of transmembrane proteins are involved with facilitated transport?

Answer 20

channel; carrier

Question 21

channel vs. carrier?

Answer 21

CHANNEL: faces extra and intra cellular environments

CARRIER: change shape to facilitate the movement of molecules.

Question 22

what are aquaporins?

Answer 22

porin that allows water to flow through rapidly

Question 23

porins and ion channels are part of what type of diffusion?

Answer 23

passive

Question 24

active transport tends to rely upon which type of proteins?

Answer 24

carrier

Question 25

what are the two types of active transport?

Answer 25

primary; secondary

Question 26

primary vs. secondary active transport?

Answer 26

PRIMARY: uses ATP directly SECONDARY: uses EC gradient produced by primary active transport

Question 27

can you give an example of primary active transport?

Answer 27

Na/K pump

Question 28

what is cytosis?

Answer 28

bulk transport of large, polar molecules

Question 29

bulk transport of large, polar molecules is called what?

Answer 29

cytosis

Question 30

what are the two types of cytosis?

Answer 30

endo and exocytosis

Question 31

what is a type of endocytosis where a cell engulfs undissolved materials

Answer 31

phagocytosis

Question 32

phagocytosis forms

Answer 32

vacuoles (phagosomes)

Question 33

what is a type of endocytosis where a cell engulfs dissolved materials?

Answer 33

pinocytosis (cellular drinking_

Question 34

what is pinocytosis?

Answer 34

cellular drinking

Question 35

pinocytosis forms

Answer 35

vesicles

Question 36

receptor-mediated endocytosis forms

Answer 36

vesicles

Question 37

organelles are enclosed by a ?

Answer 37

phospholipid bilayer

Question 38

membrane-bound organelles are associated with which cell type?

Answer 38

eukaryotes

Question 39

cytosol vs. cytoplasm?

Answer 39

cytosol: intracellular fluid cytoplasm: everything within the cell

Question 40

what is the nucleus?

Answer 40

membrane-enclosed organelle that contains most of a eukaryotic cell's genetic material

Question 41

do prokaryotes have a nucleus?

Answer 41

no they have a nucleoid

Question 42

the nucleus contains an aqueous

Answer 42

nucleoplasm

Question 43

what is the inner and outer membrane of the nucleus called?

Answer 43

nuclear envelope

Question 44

what is the space between the inner and outer nuclear membranes?

Answer 44

perinuclear space

Question 45

what is the nuclear lamina?

Answer 45

what is a dense and fibrous network of proteins associated with the inner membrane of the nuclear envelope

Question 46

what is a dense and fibrous network of proteins associated with the inner membrane of the nuclear envelope

Answer 46

what is the nuclear lamina

Question 47

_______ are a type of intermediate filament that make up the nuclear lamina

Answer 47

lamins

Question 48

what are lamins?

Answer 48

a type of intermediate filament that make up the nuclear lamina

Question 49

what functions to provide structural support to the nucleus, regulate DNA organization, DNA replication, and cell division

Answer 49

nuclear lamina

Question 50

the nuclear envelope has holes called what?

Answer 50

nuclear pores