photosynthesis

Question 1

how can glucose be used as fuel during respiration

Answer 1

chemical energy is stored within the bonds of glucose

the breakdown of glucose during respiration releases energy needed to phosphorylate ADP

so ATP produced during respiration, can be used as energy currency in reactions in cells
hydrolysis of ATP releases an inorganic phosphate aswell as a small amount of energy

the ADP and Pi produced during hydolysis of ATP can be recycled to make more ATP during respiration

Question 2

what is an anabolic reaction

Answer 2

complex molecules from simpler ones, requires energy usually from ATP

Question 3

stroma

Answer 3

cytoplasm-like fluid in chloroplasts

Question 4

what are lamellae

Answer 4

membranous channels that connect grana which ensure the sacs are connected but distanced from each other

Question 5

starch granule function

Answer 5

short-term energy storage after photosynthesis

Question 6

grana structure

Answer 6

-large surface area maximising amount of photosystems and light absorption
-more membrane area for proteins like electron-carriers and ATP synthase

Question 7

thylakoid membrane structure

Answer 7

thylakoid space allows proton gradients to be established, small volume in thylakoid space so gradient can be established quickly

Question 8

what are the products of photosynthesis

Answer 8

GALP- used to produce biological molecules like amino acids- protein synthesis

photosynthesis produces glucose which can be used to make many important biological molecules like

fatty acids form the tails of lipid molecules like triglycerides and phospholipids

Question 9

what is GP used to produce

Answer 9

-amino acids, protein synthesis
-fatty acids, tails of lipid molecules like phospholipids and triglycerides

Question 10

what is GALP used to produce

Answer 10

-nucleic acids, RNA and DNA (pentose sugar, phosphate group & nitrogenous base)
-glycerol, lipids
-hexose sugars, can be used to make other hexose sugars like sucrose

Question 11

sucrose usage in plants

Answer 11

transported in plant through phloem via translocation, moved from source to sinks

can be broken down into fructose and glucose to be used as energy for the plant

can be converted into cellulose for cell wall synthesis

Question 12

what is a sieve tube element

Answer 12

single specialised cell that make up sieve tubes

Question 13

companion cells

Answer 13

-control the metabolism of their associated sieve tube element, lots of mitochondira provide ATP for the active transport into and out of companion cells

-helps loading and unloading of assimilates (organic compounds used by plant), transport proteins in plasma membrane move assimilates into and out of sieve tube elements

-nucleus , RER , other oganelles provide metabolic support to sieve tube elements and help the loading and unloading of assimilates

-companion cells also have plasmodesmata,links sieve tubes to elements, allows assimilates to be transported from companion cells to sieve tubes

Question 14

whatre plasmodesmata

Answer 14

narrow threads of cytoplasm connecting the cytoplasm of neighbouring cells
allows substances to be transported between cells-cell to cell communication

Question 15

whatre assimilates transported by

Answer 15

translocation

Question 16

describe translocation

Answer 16

the transport of compounds UP and DOWN
-bi-directional
-requires energy (active)
-occurs in phloem

Question 17

middle lamella

Answer 17

outermost layer of plant, sticks adjacents plant cells together

provides stability to the plant

Question 18

amyloplasts

Answer 18

membrane-bound organelle containing starch granules

responsible for storing starch in plants then converting it back to glucose when needed

Question 19

tonoplast

Answer 19

selectively permeable membrane surrounding vacuole

controls what can enter and leave vacuole

Question 20

vacuole structure and function

Answer 20

-contain sap (mixture of water, sugar, waste, minerals, enzymes)
-keep turgid which prevents plant form wilting
-can break down and isolate unwanted chemicals in plant cells
(store excess water and waste,

Question 21

what colour is nucleolus under microscope

Answer 21

black

Question 22

turgor

Answer 22

rigidity of cells due to contents ,fluid in a cell pushing membrane against cell wall

Question 23

pits

Answer 23

very thin region of cell wall
pits in ADJACENT cell walls lined up in pairs
facilitates transport of substances between cells

Question 24

whatre xylem vessels made of

Answer 24

dead cells
cell walls contain lignin
enables vessels to withstand pressure from moving column of water
pits arent lignified

Question 25

what do xylem vessels look like

Answer 25

long, hollow like a straw

Question 26

why don't xylem vessels contain cytoplasm or other organelles

Answer 26

-made of dead cells -could slow down the flow of water

Question 27

function of xylem vessels

Answer 27

transport dissolved minerals and water around the plant involved in structural support one direction, up from roots to leaves

Question 28

what is transport in xylem vessels driven by

Answer 28

transpiration-water leaving leaves by evaporation cohesion-tension theory, water molecules stick together and get pulled up through xylem

Question 29

what kind of movement of water do pits allow

Answer 29

lateral (horizontal)

Question 30

what do phloem transport

Answer 30

organic compounds from sources to sinks the organic compounds are dissolved in water to make sap can occur bidirectionally, translocation

Question 31

is phloem made up of dead cells?

Answer 31

No

Question 32

phloem structure

Answer 32

made up of various cell types but mainly sieve tube elements which are the main transportation cells and companion cells also contain parenchyma for storage and strengthening fibres

Question 33

sclerenchyma fibres

Answer 33

-lignified, provide plant stem with support -no pits -long, hollow tubes (have end walls present) -have more cellulose in their cell walls than other plant cells

Question 34

mesophyll

Answer 34

internal tissue in leaf cells between epidermal layers of leaves main function is photosynthesis as mesophyll contains many chloroplasts

Question 35

parenchyma

Answer 35

essentially tissue tissue primarily composed of living cells with thin cell walls phloem parenchyma has functions in organic compound transport found throughout the plant

Question 36

how do parenchyma help with storage in phloem

Answer 36

accumulate and store various substances like starch and oils other nutrients in their vacuoles

Question 37

what do sieve tube elements line up to form

Answer 37

a continuous tube

Question 38

how do the structural features of phloem SIEVE TUBES aid in its function

Answer 38

-sieve plates with sieve pores=allows for continuous movement of organic compounds -cellulose cell wall=strengthens wall to wihtstand the hydrostatic pressures that move the assimilates -no nucleus, vacuole ribosomes in mature cells=maximises space for translocation of assimialates -thin cytoplasm=reduces friction to facilitate the movement of assimilates

Question 39

do sieve tubes and companion cells contain nuclei, vacuoles and ribosomes?

Answer 39

companion cells do (helps sieve elements with loading and unloading of assimilates) sieve tubes dont (maximises space for translocation of assimilates)

Question 40

vascular bundles: which vessel is nearest the centre?

Answer 40

xylem

Question 41

what is pith in the vascular bundle

Answer 41

soft, spongey tissue in centre of some plant stems often acting as a storage area