Term 1 Flashcards
Why do plants photosynthesise
To convert energy from the sun into glucose for the respiration and other cellular processes
What is the photosynthesis equation
Carbon dioxide +water> oxygen +glucose
State the function of the stomata
It controls gas exchange and lets gas like o2 and co2 in and out of the leaf
What is the function of the upper epidermis
The upper epidermis is a transparent layer and let’s light in for the palisade layer
What is a potometer used for
Measure the rate of transpiration (mm/hour)
State the equation to estimate transportation
Distance travelled by air bubble(mm) divided by the given time(hr)
Describe in detail the factions that can affect transpiration rate
Light intensity- brighter=stomata open=transpiration possible
Temp=hotter=particles have more energy to diffuse=evapourate
Air movement=fast wind=water vapour is taken from leaf surface
Humidity=low water on leaf evaporates into surrounding air
What are leaves adapted in marram grass to reduce the transpiration rate?
Marram grass > leaves curl into a cylinder to protect stomata on the inside +outer layer has thick waxy cuticle
State the e key difference between xylem and phloem
Xylem transports water,unidirectional flow, dead cells joined end to end
Phloem transports food/glucose multidirectional flow. Live cells which are separated by membranes
What are vitamins and nutrients needed for
For essential function and growth to make organic molecules to protein and DNA
Define mineral deficiency
A lack of minerals necessary for healthy growth
What does NPK stand for
N-nitrates
P-phosphates
K-potassium
Why are NPK they each important for ensuring the healthy growth of a plant
Nitrates makes amino acids and protein and it’s needed for cell growth
Phosphate is making DNA and cell membranes and it’s needed for respiration and growth
Potassium is making enzymes and needed for photosynthesis and respiration
Wha this glucose made in photosyntheses used for
- Energy source
- Plant energy storage
3.plant building material
4.production of other types of foods
Define active transport and give an example of this
Active transport is the movement of particles/molecules from a low to a high concentration against a concentration gradient
E.g absorbing mineral ions from the soil
Define transportation
The process of water cycling through the plants and evaporating out the stomata in the leaf
Where does the most transportation take place
Leafs
What does the transpiration steam carry
Minerals dissolving water
State the four factors that can affect tramp rate
Light intensity
Humidity
Air flow
Temp
Describe the effect of temp on transpiration rate
As temp increases transpiration rate increases as the water particles have more energy to evaporate and diffuse out of the stomata
Describe the effect of lower humidity on the transpiration rate
Faster transpiration rate as there is a greater difference in the water concentration inside the leaf compared to outside
Describe the effect of lower light intensity on transpiration rate
Decreases transportation rate as stomata closes in darker conditions (plants don’t need CO2 for photosynthesis) therefore very little can escape
Calculate the transportation rate if the bubble on the potometer moved 35mm in 10 min
Speed =distance moved/ time taken
Speed=35/10=3.5 mm/ min
Name the top and bottom side of the leaf
Waxy cuticle
What are the pores in the underside of the leaf called (singular/plural)
Stomacone, stomata
Where does the most photosynthesis occur in the leaf
Palisade layer because it is densely packed with chloroplasts
What controls the loss of water from the leaf and gas exchange
Guard cells which open and close
Why is the upper epidermis transparent
To let light into the leaf so the leaf can photosynthesise
State the function of the waxy cuticle
Prevents water loss out of the leaf by evaporation
What is found in the vascular bundle
Xylem at the top
And phloem and the bottom
Why does the spongy layer have air spaces
To allow gasses such as CO2 and O2 to diffuse in and out of the cells
Describe how the root hairs take in both water and mineral
It takes in water by osmosis which is a higher water concentration to a lower concentration inside roots.
It takes minerals by active transport which lower in soil to higher concentration inside the root
Describe the function be adaptations of the phloem
Transports food substances (sucrose) to rest of plant (both directions) phloem tubes are made of columns of elongated cells. Pores in end walls to allow substances through
Describe the function and adaptations of the xylem
Carey water and mineral salts from the roots to let stem/ leaves made of dead cells joined to end with no end walls between them
Explain transportation
The process of water cycling through the plant and evaporating out the stomata and in the leaf
Name me the leaf form top to bottom
Waxy cuticle
Upper epidermis
Palisade layer
Spongy layer
Air spaces
Xylem and phloem (vascular bundle)
Lower epidermis
Guard cells
Stomata
What is the function of the spongy layer
To allow gases such as CO2 and O2 to diffuse in and out of the leafs easily
Describe the method to estimate transpiration rate
1 set up potometer
2 start a stopwatch and record the distance moved(per hour)
3calculate the speed of air bubble movement
