Feb. 25th - Temperature Tolerance

Question 1

Stress tolerance

Answer 1

return to homeostasis

Question 2

membrane fluidity

Answer 2

extent of molecular disorder and molecular motion within a lipid bilayer

Question 3

gel phase

Answer 3

(solid)
phospholipid tails are tightly packed together

Question 4

liquid crystalline phase

Answer 4

(fluid (optimal))
phospholipid tails can move around

Question 5

protein isoforms

Answer 5

slightly different structures (AA sequences)

may have dif. relationships with temp

(this can be good for important proteins)

Question 6

Strategies of temperature stress tolerance

Answer 6

1: alter composition of macros to preserve function
2: accumulate molecules to protect membranes and proteins

Question 7

Preserving function under temp stress by altering macros composition

Answer 7

maintain protein flexibility and membrane fluidity (lcs)
ex. isoforms … cells can change which isoforms are active/ synthesized at dif temps.

(ex. cold-adapted myosin in fish)

Question 8

Accumulating molecules to protect membranes and proteins under temp stress

Answer 8

ex. cryoprotectants at low temps!

glycerol, trehalose, proline

Question 9

cryoprotectants

Answer 9

molecules that protect cells’ proteins and membranes under extreme cold/ dehydrating conditions