Cell Transport

Question 1

What are the (4) parts of the cell membrane?

Answer 1

• Lipids
• Proteins
• Carbohydrates
• Cholesterol

Question 2

What is the function of lipids in a cell membrane?

Answer 2

Phospholipids (selectively permeable) - lets some stuff pass, others get blocked

Question 3

What is the function of proteins in a cell membrane?

Answer 3

Act like a door to let in big molecules

Question 4

What is the function of carbohydrates in a cell membrane?

Answer 4

Act as identifiers

Question 5

What is the function of cholesterol in a cell membrane?

Answer 5

Keeps the consistency of the membrane in cold or hot

Question 6

What do cell membranes do?

Answer 6

Help maintain homeostasis controlling what substances may enter or leave the cell

Question 7

Passive Transport

Answer 7

• High to low concentration
• With the concentration gradient
• Does not use ATP
• 3 types

Question 8

Diffusion

Answer 8

Movement of molecules from an area of high to low concentration

Question 9

Concentration Gradient

Answer 9

Difference in the concentration of molecules across a distance

Question 10

For how long will molecules continue to diffuse?

Answer 10

Until they reach equilibrium

Question 11

Equilibrium

Answer 11

Equal concentration of molecules throughout

Question 12

What is let into the cell membrane? What are two examples?

Answer 12

• Small, polar molecules
• O2, CO2

Question 13

Polar

Answer 13

Has a negative and positive side

Question 14

What is not let into the cell membrane? What are three examples?

Answer 14

• Large, non-polar molecules and ions
• Glucose (C6H12O6), Lipids, Na+, Cl-

Question 15

Facilitated Diffusion

Answer 15

Method that molecules that are too large to enter the cell but are needed for survival use to enter the cell

Question 16

How do molecules enter through facilitated diffusion? (2)

Answer 16

• Carrier Proteins
• Ion/Protein Channels

Question 17

What is true about carrier proteins?

Answer 17

They can only transport one thing determined by its shape, similar to an ezymes/substrate

Question 18

Ion Channel

Answer 18

How charged particles enter the cell

Question 19

How are ion channels triggered to open? (3)

Answer 19

• Stretching the membrane
• Electrical signals
• Chemical in the cytoplasm

Question 20

Osmosis

Answer 20

Passive transport of water across a membrane

Question 21

Hypotonic

Answer 21

More solutes (salt) inside than outside –> water goes in –> cell grows

Question 22

Hypertonic

Answer 22

More solutes (salt) outside than inside –> water goes out –> cell shrinks

Question 23

Isotonic

Answer 23

Solutes equal inside and outside –> water flows equally –> volume is the same

Question 24

Turgor Pressure

Answer 24

Plants live in hypotonic environments –> bring water into roots –> the water adds pressure to the cell walls

Question 25

Cytolysis/Cytolytic Pressure

Answer 25

Animal cells’ hypotonic environment --> cells swell so much it bursts

Question 26

Plasmolysis/Plasmolic Pressure

Answer 26

Plant cells' hypertonic environment --> water flows out of the cell --> gets crushed by the external pressure = plasmolysis (why plants wilt)

Question 27

Contractile Vacuole

Answer 27

Organelles that pump out extra water in freshwater organisms that are living in hypotonic environments so they don't grow too big and explode due to constant water intake

Question 28

Active Transport

Answer 28

- Low to high concentration - Against concentration gradient - Uses ATP

Question 29

Transport Proteins

Answer 29

Act as pumps to pump materials against concentration gradient

Question 30

What is an example of a pump?

Answer 30

Sodium - potassium pump

Question 31

What is true about pumps?

Answer 31

Need to be shielded from the lipid tails because of the polarity

Question 32

Exocytosis

Answer 32

Process of which substances in the cell are released by a vesicle (a fluid filled sac)

Question 33

Describe the process of exocytosis.

Answer 33

Golgi has modifies protein --> creates a vesicle which moves through cytoplasm --> becomes part of the membrane --> release the particles outside the cell

Question 34

Endocytosis

Answer 34

Process by which substances enter the cell

Question 35

Phagocytosis

Answer 35

Solids enter the cell

Question 36

Pinocytosis

Answer 36

Liquids enter the cell

Question 37

Describe phagocytosis.

Answer 37

Phagocytes (cells) are filled with enzymes and break up bacteria

Question 38

Channel Protein

Answer 38

Transport protein that provides a tube-like opening in the plasma through which particles can diffuse

Question 39

Transport Protein

Answer 39

Used to help substances enter or exit the cell membrane