globular proteins

Question 1

myoglobin

Answer 1

found in muscles, 1 polypeptide chain, binds to O2

Question 2

hemoglobin

Answer 2

4 polypeptide chains, 1 heme molecule binds to 4 O2 molecules

Question 3

oxyhemoglobin

Answer 3

hemoglobin plus O2, relaxed state more stable than tense state

Question 4

deoxyhemoglobin

Answer 4

has a vacant O2 binding site, tense state more stable than relaxed state

Question 5

methemoglobin

Answer 5

iron in the oxidized state (Fe3+) plus hemoglobin. can’t bind oxygen

Question 6

T (tense) state

Answer 6

more stable when oxygen is absent, stabilized by greater number of ion pairs

Question 7

R (relaxed) state

Answer 7

oxygen has higher affinity for hemoglobin, stabilized by the binding of oxygen

Question 8

what is a homotropic positive effector?

Answer 8

oxygen

Question 9

oxygen saturation

Answer 9

percentage of hemoglobin molecules that are oxygenated

Question 10

fibrous proteins

Answer 10

secondary structure, tensile strength. exhibit special mechanical properties

Question 11

collagen

Answer 11

structural connective tissue, 30% of total body protein. 1000 amino acid residues per chain, triple helix structure

Question 12

elastin

Answer 12

places you want to stretch, insoluble elastic protein. large inelastic collagen fibrils are interwoven to limit stretching + prevent tissues from tearing

Question 13

osteogenesis imperfecta

Answer 13

brittle bone disease, genetic bone disorder. mutation in type 1 collagen genes, prevent triple helix formation