Plant tissues, organs, and systems

Question 1

nucleus

Answer 1

animal/plant cells - controls activities of the cell - holds the cell’s dna

Question 2

cytoplasm

Answer 2

animal/plant cells - organelles are suspended in this jelly-like substance where chemical reactions (metabolism) occur

Question 3

cell-membrane

Answer 3

animal/plant cells - semi-permeable membrane which controls what can enter and exit the cell

Question 4

cell wall

Answer 4

plant cells - supports the cell - gives it structure

Question 5

mitochondria

Answer 5

animal/plant cells - powerhouse of the cell - where aerobic respiration occurs

Question 6

ribosomes

Answer 6

animal/plant cells - protein synthesis

Question 7

chloroplasts

Answer 7

plant cells - where photosynthesis occurs - contain chlorophyll

Question 8

adaptations of a leaf

Answer 8

upper epidermis is mostly transparent to allow light to reach palisade cells; air spaces allow for faster diffusion; waxy cuticle prevents water loss and infection; stomata control movement of gases

Question 9

what are the names of different cells/tissues in a leaf

Answer 9

cuticle, upper/lower epidermis, palisade mesophyll, spongy mesophyll, guard cells, stomata

Question 10

what are guard cells

Answer 10

specialised lower epidermis cells which control the opening and closing of stomata

Question 11

examples of cells in plants

Answer 11

root hair cells, guard cells

Question 12

examples of tissues in plants

Answer 12

epidermis, spongy mesophyll, palisade mesophyll, xylem, phloem, meristem

Question 13

organs in plants

Answer 13

roots, leaves, flowers, fruits, seeds, stem

Question 14

organ system in plants

Answer 14

transpiration, translocation

Question 15

what is the function of a flower

Answer 15

reproduction - attracts pollinators (brightly coloured, nectar, scent)

Question 16

function of seeds

Answer 16

reproduction, growth

Question 17

function of leaves

Answer 17

photosynthesis

Question 18

function of stem

Answer 18

keeps plant upright to absorb light, transport in xylem and phloem

Question 19

function of roots

Answer 19

active transport of minerals, osmosis of water

Question 20

composition of xylem

Answer 20

made of dead cells - no end walls; less obstruction to movement of water; flows in hollow tube - one way flow - transports water and minerals - walls stiffened with lignin

Question 21

composition of phloem

Answer 21

2 way flow - transports water and food (glucose and sucrose, fatty acids, oils, amino acids) - cells have end walls with perforations; sieve plates - companion cells; change flow direction; active transport; full of mitochondria

Question 22

meristem tissue

Answer 22

unspecialised cells - growth - found in tips of roots and shoots

Question 23

transpiration

Answer 23

process where water evaporates and diffuses out through stomata - pulls more water up plant from root - transpiration stream (some water used in photosynthesis)

Question 24

what quality of water enables transpiration to occur

Answer 24

water is polar - molecules stick together - water is pulled up in transpiration stream

Question 25

factors affecting rate of transpiration

Answer 25

light intensity, wind speed, humidity, temperature

Question 26

how does light intensity affect rate of transpiration

Answer 26

makes stomata open if brighter - lower LI, stomata close. if stomata open - transpiration is faster as water can diffuse out of leaves

Question 27

how does wind speed affect rate of transpiration

Answer 27

higher wind speed - faster transpiration - will blow air with high water concentration away - becomes dilute - steeper concentration gradient - diffuse faster

Question 28

how does temperature affect rate of transpiration

Answer 28

high temperature - particles have higher kinetic energy - evaporate faster as molecules break apart and become gas - as particles move faster

Question 29

how does humidity affect rate of transpiration

Answer 29

high humidity - slow transpiration - if air is concentrated with water (humid) - shallow concentration gradient

Question 30

process of transpiration

Answer 30

osmoses from soil into root hair cell (dilute to concentration solution) - move down concentration gradient. moves to root cell. moves through xylem - transpiration stream - pulls more water up. moves to spongy mesophyll - lower epidermis - stomata. diffuse and evaporate out - high water conc in cells - low in air - moves down conc gradient

Question 31

plant adaptations to reduce water loss

Answer 31

rolled leaves, sunken stomata, spikes not leaves, hairs on leaves, shallow & widespread roots, fewer stomata, thick waxy cuticle

Question 32

how do rolled leaves and sunken stomata reduce water loss

Answer 32

rolled leaves - reduce exposure of stomata to air, reducing evaporative water loss. sunken stomata - reduces air movement over stomata, creating humid microclimate, reducing evaporation rate.

Question 33

how do spikes not leaves reduce water loss

Answer 33

prevent animals from eating plant - spines break up airflow - reduces evaporation - trapped air can create a buffer zone with slightly more moist air. spines also help collect water from fog.

Question 34

how do hairs on leaves reduce water loss

Answer 34

trap air close to leaf - creates microclimate around leaf - as leaf loses water microclimate becomes humid - hairs prevent this from being blown away - humidity - slower transpiration rate

Question 35

how do shallow, widespread roots reduce water loss

Answer 35

spread wide to collect surface water from wide area of land

Question 36

how do fewer stomata reduce water loss

Answer 36

less stomata - less places for water to evaporate/diffuse out of leaf

Question 37

how does a thick waxy cuticle reduce water loss

Answer 37

stops vapour escaping through epidermis - shiny to reflect heat - lower temperature - slower transpiration

Question 38

translocation

Answer 38

transportation of food substances produced in photosynthesis, to places where they are needed eg storage organs (bulbs and tubers), developing seeds, growing parts of a plant

Question 39

what is the part of a plant which produces food called

Answer 39

a source

Question 40

what is the part of a plant which store/use food called

Answer 40

sink

Question 41

process of translocation

Answer 41

pressure flow - at source sugar moves into phloem cells through active transport - water follows through osmosis - water creates turgor pressure in sieve elements, forcing sugars down towards sinks, at sinks sugars actively removed and water follows, so high water potential and low turgor pressure is created