macromolecules

Question 1

Polysaccharide Properties for starch

Answer 1

plant cell, energy storage, 1-4 glycosidic linkage makes chains, side chain to main chain by 1-6 glycosidic, monomer is glucose, and can be digested by humans

Question 2

polysaccharide properties for glycogen

Answer 2

animal cell, energy storage, 1-4 glycosidic linkage makes chains, side chain to main chain by 1-6 glycosidic, monomer is glucose, can be digested by humans

Question 3

polysaccharide properties for cellulose

Answer 3

plant cell, structural storage, 1-4 glycosidic linkage makes chains, monomer is glucose, NOT digestible by humans

Question 4

triglycerides =

Answer 4

1 glycerol + 3 fatty acids

Question 5

saturated vs unsaturated fats

Answer 5

refers to whether there are double bonds in the hydrocarbon chain or not
- saturated = no double bonds
- unsaturated = double bonds

Question 6

lipids with saturated fatty acids…

Answer 6

pack together well

Question 7

lipids with unsaturated fatty acids …

Answer 7

do not pack together well

Question 8

unsaturated can be either … and this means …

Answer 8

they can either be cis or trans
- cis will form a bend (their carbons will) c^c
- trans has no bend, shaped like a saturated fat

Question 9

phospholipids in biological membranes form a …

Answer 9

lipid bilayer

Question 10

what is the difference between polar head groups and fatty acid tails

Answer 10

• polar head groups are hydrophilic
• fatty acid tails are hydrophobic

Question 11

double-membraned organelles (like mitochondria) have…

Answer 11

two lipid bilayers
- mitochondrial outer membrane
- mitochondrial intermembrane space
- mitochondrial inner membrane

Question 12

steroids are …

Answer 12

amphipathic

Question 13

proteins are…

Answer 13

polymers of amino acids linked end-to-end in a specific sequence

Question 14

amino acid structure is:

Answer 14

• a carboxyl group
• a beta carbon
• an amino group
• r group (different for each amino acid)

Question 15

peptide bonds which are between… are formed by…

Answer 15

between two amino acids (from the beta carbon?) and condensation reactions

Question 16

properties of r groups establish… and remember there … categories of AAs and … unique AAs

Answer 16

they establish the properties of the proteins
- there are three categories of AAs and 3 unique AAs

Question 17

side chains in group a are…

Answer 17

hydrophobic, and associate with each other via Van der Waals forces and hydrophobic interactions

Question 18

what are the three categories of AAs

Answer 18

group a: nonpolar AAs (hydrophobic)
group b: polar, uncharged amino acids (hydrophilic)
group c: polar, charged amino acids (hydrophilic)

Question 19

examples of each of the categories of AAs

Answer 19

group a: glycine, alanine, proline
group b: serine, asparagine, glutamine
group c: glutamate (acidic) and arginine (basic)

Question 20

proteins are an important component of…

Answer 20

membranes

Question 21

what are the three types of membrane proteins?

Answer 21

1. integral
2. peripheral
3. lipid-anchored

Question 22

integral membrane proteins penetrate…

Answer 22

into the hydrophobic region of the bilayer
- they are an asymmetric shape
- are amphipathic
- beta-helix

Question 23

peripheral membrane proteins:

Answer 23

• are electrostatic bonds and hydrogen bonds
• are dynamic
• asymmetrical distribution

Question 24

lipid anchored:

Answer 24

• GPI is always facing away from cytoplasm (Glycosyl Phosphatidyl Inositol)
• other types of lipid anchored proteins attach directly to a lipid

Question 25

integral parts of the fluid mosaic model

Answer 25

- glycoproteins - peripheral protein - hydrophobic beta helix - integral proteins - oligosaccharide - cholesterol - glycolipid - phospholipid

Question 26

what and who founded the movement of membrane proteins

Answer 26

- the 1970 classic experiment by larry frye and michael edidin - it is the fusion of human and mouse cells

Question 27

first 3 steps of Frye and Edidin experiments...

Answer 27

1. mouse and human cells with mouse-specific (m) and human specific (h) membrane proteins 2. hybrid cell produced by virus-induced fusion 3. membrane proteins labeled with specific fluorescent antibodies

Question 28

last two steps of the frye and edidin experiment

Answer 28

4. labeled proteins begin to mix in a few minutes 5. labeled proteins completely mixed after 40 minutes

Question 29

what is the technique for studying membrane protein mobility with the acronym FRAP?

Answer 29

fluorescence recovery after photobleaching - proteins are covalently linked to a fluorescent dye or use genetic techniques to create a GFP-tagged version of the protein - frap experiment can label any cell surface molecule ex. proteins or lipids

Question 30

steps of FRAP on a protein

Answer 30

1. unlabeled cell surface 2. cell surface labeled with fluorescent dye 3. laser beam bleaches an area of the cell surface 4. fluorescent-labeled molecules diffuse into bleached area 5. bleached area disappears as lipids move laterally

Question 31

proteins do not always...

Answer 31

moved freely in the membrane

Question 32

restriction of the movement of a protein

Answer 32

a- random diffusion b - immobilized as a result of interaction with underlying membrane skeleton c - being moved in particular direction bc interaction with a motor protein at cytoplasmic surface d - restricted by other integral proteins e - restricted by fences of proteins f - restrained by extracellular materials

Question 33

lipid rafts have 4 main features:

Answer 33

1. tightly packed 2. sphingolipids (no glycerol, long fatty acid tails) 3. cholesterol 4. receptor proteins binding external chemical signals can move to rafts