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Flashcards in Chapter 6 Deck (26):
1

what structural features do all lipids have in common?

-hydrocarbons
-reduced carbons (high energy storage)
-non polar parts

2

hydrophilic

-polar
-electronegative difference
-interact with water
-soluble
-carbohydrates, some amino acids, nucleic acids

3

hydrophobic

-non polar
-equal electronegativity
-does not interact with water
-insoluble
-lipids, some amino acids

4

amphipathic molecule

-molecule can divide in half
-non polar tail with polar head in a lipid

5

what characteristic is shared by all polypeptides, nucleic acids, and polysaccharides, but not by lipids?

-no polymers formed by monomers in lipids
-lipids formed through dehydration reactions (not condensation)

6

how does membrane change in presence of C=C double bond in fatty acids of phospholipids?

-double bonds in unsaturated hydrocarbon tails create kinks, taking up more space
-reduces strength of van der waals interactions
-weakens barrier to solutes
-allows molecules to leak through
-more fluid

7

how does membrane change with no double bonds

-saturated tails without double bonds take up less space
-pack more densely
-stronger van der waal force (attraction)
-less permeable membranes
-less fluid

8

diffusion

movement of solute molecules from low to high concentration gradient

9

osmosis

movement of water along semi-permeable membrane from low to high concentration

10

selective permeability

-some molecules can go through easily, when others can't or are just slower

11

permeable examples

-non polar
-steroids
-small molecules (O2, CO2, H2O)

12

non permeable examples

-polar / charged
-macromolecules
-integral proteins

13

carrier proteins

-membrane proteins that change shape during transport process
-powered by diffusion
-passive
-binds molecule then changes shape

14

channel proteins

-structured for specific molecules to pass through
-very selective
-passive
-depends on gradient/ concentration

15

passive transport

-powered by diffusion (random movement)
-along electrochemical gradient

16

what could you add to -C-C-C- to make it hydrophobic or hydrophilic?

-add Hs to make it hydrophobic
-add phosphate (polar Os) or OH to make it hydrophilic

17

what makes steroids, phospholipids, and fats lipids?

-made of hydrocarbon chains
-insoluble in water
-amphipathic

18

which lipids undergo condensation reactions?

-phospholipids are made through condensation reactions
-when tail is added to the head, an H2O is lost

19

integral membrane proteins

-amphipathic
-contain both polar and nonholar amino acids
-can make itself hydrophobic or hydrophilic
-phospholipid bilayer is dynamic and fluid

20

hypertonic relationship cell can have with environment

-solute concentration is greater outside the cell than inside
-cell shrinks

21

hypotonic relationship cell can ave with environment

-solute concentration is lower outside the cell than inside
-cell expands

22

isotonic relationship cell can have with environment

-solute concentration is the same on either side of cell membrane

23

why does detergent kill bacteria

-detergent is an amphipathic molecule that forms micelles in water
-micelles isolate and break down bacteria by coating hydrophobic tails and dissolve them in water

24

gated channels

open and close in response to signal to facilitate diffusion

25

why does active transport require an energy source

-movement against gradient requires energy
-counteracts decrease in entropy that happens when molecules/ions are concentrated
-energy comes form phosphate group from ATP

26

difference between K+ and Na+ externally and in the cytoplasm

-Na+ ions bind to inside of site and are released outside
-K+ binds to site from outside and moves to inside