cell membrane

Question 1

another name for cell membrane

Answer 1

plasma membrane

Question 2

cell membrane functions

Answer 2

• acts as a protective barrier that regulates which particles can enter and exit the cell (selectively permeable/ semi-permeable) *not all cells have the same permeability
• the membrane separates all cells from the external enviornment
• the cell membrane also works to keep homeostasis

Question 3

cell membrane structure

Answer 3

two layers of lipid material with protein molecules interspread.
* called a phopholipid bilayer

Question 4

structure of the phospholipid

Answer 4

head and tail
- head : phosphate group (polar, hydrophilic, and water soluble)
- two tails : fatty acids (non-polar, hydrophobic, water incoluble)
the water soluble ends face the outer environment and inner cell components

Question 5

hydrophobic

Answer 5

water hating

Question 6

hydrophilic

Answer 6

water loving

Question 7

the fluid mosaic model

Answer 7

a model that shows and describes the cell membrane

Question 8

parts of the cell membrane

Answer 8

phospholipid bilayer, proteins, cholesterol, glycoproteins, glycolipid

Question 9

phospholipid bilayer

Answer 9

acts as a barrier to the passage of molecules and ions into and out of the cell

Question 10

proteins

Answer 10

• transport (channels or pumps for moving substances)
• receptors (for signaling)
• adhesion (stick to surfaces like other cells)
• enzymatic actions (enzymese are proteins that buils up molecules)

Question 11

cholesterol

Answer 11

• role in membrane fluidity and stability which changes with temperature
• plants do not have this
• cholesterol is a type of lipis/fat

Question 12

glycoproteins

Answer 12

• recognition (ie. blood types)
• receptors for hormones
• made of a carbohydrater chain and protein

Question 13

glycolipid

Answer 13

• provide energy
• cell recognition (ie. to recognize other cells)
• made of a lipid/ fat and a carbohydrate chain

Question 14

peripheral protein

Answer 14

into the cytoplasm