membranes and sortings

Question 1

which organelles have. double membrane?

Answer 1

mitochondria, nucleus,

Question 2

do steroid hormones to diffuss across the membrane?

Answer 2

yes

Question 3

what do biological membranes consist of?

Answer 3

a bilayer of lipid molecules

Question 4

what are biological membranes?

Answer 4

impermeable barrier to water soluble molecules

Question 5

what do lipid molecules in the membranes do?

Answer 5

spontanedously aggregate to form micelles

Question 6

what do lipids in the membrane have?

Answer 6

hydrophilic head
hydrophobic tail

Question 7

what is amphipathic?

Answer 7

molecule with water-loving and water-hating parts.

Question 8

what is hydrophilic?

Answer 8

water loving

Question 9

what is hydrophobic?

Answer 9

water hating

Question 10

what does passive transport do?

Answer 10

protein binds molecules on the high concentration side and moves them to the low concentration side

Question 11

how does passive transport work?

Answer 11

does not require energy from ATP or light.
moves molecules from high to low concentrations.

Question 12

types of coupled transporters?

Answer 12

antiporters
symporters
uniporters

Question 13

what is an antiporter?

Answer 13

transports two molecules in opposite directions - one in one out

Question 14

what is a symporter?

Answer 14

transports two molecules in the same direction?

Question 15

what is a uniporter?

Answer 15

transports one molecule

Question 16

how can the ion channel opening be regulated?

Answer 16

by the binding of a ligand to the extracellular or intracellular face of the ion channel
by the voltage across the membrane

Question 17

what can ion channels do?

Answer 17

apply selective filter to only let specific ions through
can be open or closed