Plant cells

Question 1

chloroplast structure

Answer 1

-surrounded by a double membrane
- contains stroma
contains thylakoids, stacked into grana where the chlorophyll is located

Question 2

stroma

Answer 2

jelly like material in the chloroplast which consists of circular DNA, ribosomes and start granules and enzymes

Question 3

function of chloroplasts

Answer 3

• site of photosynthesis
• light dependent reactions of photosynthesis takes place in the Thylakoid membrane, so it consists largely of chlorophyll

Question 4

vacuole structure

Answer 4

large membrane bound organelle filled with cell sap, and it is enclosed by tonoplast which is a selectively permeable membrane

Question 5

cell sap

Answer 5

aqueous solution with dissolves ions, food waste products and pigment

Question 6

function of vacuole

Answer 6

• maintains cell turgor (pressure) for structural support
• stores nutrients, waste products and pigments

Question 7

amyloplast structure

Answer 7

startch granules covered with double membrane which forms amynoplast

Question 8

cell wall composition

Answer 8

made of cellulose

Question 9

cell wall structure

Answer 9

rigid, semi permeable out layer which contains plasmodesmata

Question 10

cell wall function

Answer 10

• provides mechanical strength and support, maintains shape
• protects against physical damages and osmotic stress
• allows water and dissolves substances to pass freely

Question 11

types of cell wall

Answer 11

primary cell wall
secondary cell wall

Question 12

primary cell wall

Answer 12

1. microfibrils deposit on the matrix randomly, forming a mesh-like structure
2. random arrangement of microfibrils gives stretching capability to the primary cell wall allowing it to grow

Question 13

primary cell wall formation

Answer 13

forms while the cell is growing and dividing
- flexible, allowing cell expansion

Question 14

function of primary cell wall

Answer 14

permits growth
permeable: allows water, nutrients to pass freely
provides mechanical support

Question 15

matrix in primary cell wall

Answer 15

made out of hemicellulose and pectins

Question 16

secondary cell wall

Answer 16

1. microfibrils arrange parallel to each other forming a layer, and these layers of microfibrils deposit perpendicular to each other
2. extra deposition of lignin and arrangement of microfibril layers increases the stability giving it its strength

Question 17

matrix in secondary cell wall

Answer 17

hemicellulose, pectin and lignin

Question 18

formation of secondary cell wall

Answer 18

forms once cell stops growing
- deposited between the primary cell wall and the plasma membrane

Question 19

function of secondary cell wall

Answer 19

provides strength
waterproofing: important in xylem vessels
protection

Question 20

pit

Answer 20

thin regions in the secondary cell wall of plant cells that allow exchange of substances between adjactent cells

Question 21

structure of pits

Answer 21

1. found in secondary cell wall, where lignin deposition is absent

Question 22

plasmodesmata

Answer 22

microscopic regions that traverse the cell walls of the plant cells, connecting the cytoplasm of adjacent cells for communication and transport

Question 23

location of plasmodesmata

Answer 23

found in primary cell walls

Question 24

function of plasmodesmata

Answer 24

active transport and communication between cytoplasm of cells