Brainscape's Knowledge GenomeTM

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


See full index

Biology 1 > Ch. 7 Review > Flashcards

Ch. 7 Review Flashcards

1
Q

What holds the lipid bilayer together?

A

Hydrophobic interactions

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

Where are the hydrophobic and hydrophilic regions of a transmembrane protein?

A

Hydrophilic- sides facing extracellular matrix and cytosol, interior of protein

Hydrophobic- outside facing lipid bilayer

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

The membrane is _______

A

FLUID

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

Phospholipids move _____ not _______

A

Laterally, they don’t FLIP-FLOP

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

Why don’t phospholipids flip-flop?

A

The phospholipids would have to then invert themselves, this requires more energy then lateral movement and it’s rare

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

Do proteins in the membrane move?

A

Yes, only laterally for the same reasons as phospholipids

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

Fluidity is essential for cells, what are the two reasons?

A
  1. for permeability (slight!)
  2. so the membrane proteins can function (ex. ETC in mitochondria for fluidity)

Ex homeostasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What factors influence fluidity?

A
  1. temperature- High temp more fluid, low temp less fluid
  2. type of fatty acids- saturated vs. unsaturated (more fluid)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

At a high temp there are more _______ fatty acids, at a low temp there are more _______ fatty acids

A

saturated, unsaturated

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

Single celled life can ______ which types of fatty acids are present?

A

alter

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

Membranes are mosaics that ______

A
  1. contain a diverse set of proteins
  2. some are embedded, some are not
    -integral vs peripheral proteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Membranes also contain 4 things

A
  1. glycoproteins (oligosaccharide attached to amino acide side chain)
  2. glycolipids (oligosaccharide and lipid)
  3. oligosaccharides
  4. receptors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Proteins have a specific _______ which determines its _______

A

orientation, function

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

What are the 6 types of membrane proteins mentioned in lecture?

A
  1. transport
  2. enzymatic activity
  3. signal transduction
  4. cell to cell recognition
  5. intercellular signaling (cell junctions)
  6. attached to the cytoskeleton
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What do cells need from the environment?

A
  1. nutrients for energy, vitality and growth
    -sugars, amino acids, fatty acids
    -Na+ K+, vitamins allow us to do biochemistry
  2. Gases (ex. O2)
  3. Need to eliminate waste
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Membrane proteins maintain what and accommodate for what?

A

Must maintain internal environment, membrane proteins accommodate for the diversity of needs and nutrients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the barriers to getting nutrients into the cell? What is the solution?

A

PROBLEM
1. nutrients are polar and charged, proteins need to help

  1. The cell membrane has a hydrophobic core

SOLUTION
Membranes are selectively permeable

18
Q

What does selective permeability depend on?

A
  1. permeability of a pure phospholipid bilayer
  2. the presence of transport proteins
19
Q

What can cross the bilayer? What can’t?

A

CAN
small, nonpolar molecules (ex. O2)
small, polar molecules are partially blocked but can cross (ex. H2O)

CAN’T
large, polar molecules are totally blocked (ex. glucose)
charged substances of ANY size are totally blocked (ex. Na+ or K+)

20
Q

What are the two types of transport?

A

passive and active

21
Q

Is energy involved in passive transport?

A

There is no NET energy, BUT there is POTENTIAL energy

22
Q

Is energy involved in active transport?

A

YES, ATP is used

23
Q

What are the two types of passive membrane transport?

A
  1. simple diffusion (small nonpolar substances)
  2. Facilitated diffusion
    -channel and carrier proteins for polar and charged substances
24
Q

Transport and channel proteins are _______

A

SPECIFIC

25
Q

Define channel proteins

A
  1. integral membrane protein completely spanning the membrane

2.Contains a HYDROPHILIC CORE, that recognizes ONE type of solute

26
Q

How do channel proteins recognize one specific solute?

A

based on specific shape, size, and polarity. The channel protein is used by individual atoms.

27
Q

What is an example of a channel protein?

A

ion channels (Na+, K+, Ca++) aquaporins

28
Q

What is osmosis? Why is it special?

A

Osmosis is the diffusion of water

water VIOLATES high to low

water diffuses from high to low concentration, the solutes remain constant

29
Q

What are examples of osmoregulation?

A

protists- contractile vacuoles
bacteria- cell walls
plants- cell walls
animals- solute balancing

30
Q

Plants prefer which osmoregulation state? Animals prefer which one?

A

plants- hypotonic

animals-isotonic

31
Q

Carrier proteins change _______ to allow _______ solute to pass through

A

shape, ONE

32
Q

Channel proteins are ______ and _______ change shape

A

static, DON’T

33
Q

Carrier proteins can transport

A

monomers like amino acids or glucose

34
Q

Why active transport?

A
  1. so solutes can move AGAINST the concentration gradient to concentrate things within the cell
  2. requires INPUT of ENERGY
  3. requires a CARRIER protein
35
Q

What are the two types of active transport?

A

primary- used to concentrate ions via ion pumps, driven by ATP

secondary- involves movement of TWO substances, COTRANSPORT, driven by the ion gradient

36
Q

What pump is essential for osmoregulation in animal cells?

A

Sodium potassium pump, which MAINTAINS the gradient

3 Na+ out, 2 K+ in

37
Q

What is an example of a secondary active transport?

A

Na+ driven glucose transport protein

Glucose transport doesn’t need ATP BUT it needs Na+, Na+ comes from active transport of sodium potassium pump, glucose transport needs ATP SECONDARILY

38
Q

Vesicles transport ______

A

transport macromolecules, particles, and small cells

39
Q

What are the two types of vesicle transport

A

exocytosis- secretion, out of cell

endocytosis- phagocytosis, into cell

40
Q

Phagocytosis is ________ while receptor-mediated endocytosis is ________

A

nonspecific, specific

Biology 1 (9 decks)

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