plants and photosynthesis

define traspiration

loss of water from leaves by evaporation through the stomata

how does the xylem tissue obtain water fro transport

from the soil,absorbed through the roots by osmosis

state the uses of the glucose made during photosynthesis

used in respiration

stored as starch

combined with nitrates to make amino acids

used to make fats and oils and cellulose cell walls

explain the effect of carbon dioxide concentration on the rate of photosynrhesis

as carbon dioxide concenttration increases, the rate of photosynthesis also increases up to a maximum level.

this is because plants need carbon dioxide to photosynthesise.

after this point, the rate levels off because another factor is limiting the rate of photosynthesis

explain the effect of light intensity on the rate of photosynthesis

As light intensity increases, the rate of photosynthesis also increases up to a maximum level.

This is because plants need light to photosynthesise.

After this point, the rate levels off because another factor is limiting the rate of photosynthesis.

describe and explain how temperature affects the rate of transpiration

Higher temperature increases rate of transpiration.

Water molecules move faster as temperature increases.

Evaporation increases from the lower surface of the leaf.

when investigating the effect of light intensity on the rate of photosynethsis in pondweed, name 2 variables that need to be controlled

carbon dioxide concentration, temperature, species of pondweed, light source bulb

define photosynthesis

the process by which plants make glucose

how is thr palisade mesophyll cell in a leaf adapted to its function

contains lots of chloroplasts to perfrom lots of photosynthesis

when investigating the effect of light intensity on the rate of photosynthesis in pondweed,name the dependent variable

rate pf photosynthesis (number of bubbles released per minute)

explain whether photosynthesis is exothermic or endothermic

photosynthesis is endothermic as energy is transferred from the enviroment to the chloroplats by light

give 4 factors that can affect the rate of transpiration

humidity, air movement, light intensity and tamperature

explain the effect of temperature on the rate of photosynthesis

As temperature increases, the rate of photosynthesis also increases until it reaches a maximum level.

At temperatures higher than this point, enzymes denature and the rate of photosynthesis decreases.

Describe and explain how light intensity affects the rate of transpiration.

Higher light intensity increases rate of transpiration.

Rate of photosynthesis increases so more water diffuses out of the leaf.

state the function of the spongy mesophyll layer of a leaf

to allows gases to diffuse easily through it

define translocation

the transport of dissolved sugars and amino acids up and down a plant

give the word equation for photosynthesis

water + carbon dioxide → glucose + oxygen

state the function of the palisade mesophyll layer of a leaf

to perform lots of photosynthesis

why is the upper epidermal layer of a leaf transparent

to allow light to pass through

during an investigation into the effect of light intensity on rate of water uptake by plant, name the independent variable

light intensity

give 4 factors that affect the rate of photosynthesis

light intensity, temperature, carbon dioxide concentration and amount of chlorophyll

describe and explain how air movement affects the rate of transpiration

more air movement increases rate of transpiration

more water molecules are removed from the surface of the leaf

more water diffuses out of the leaf

Describe and explain how humidity affects the rate of transpiration

Higher humidity decreases rate of transpiration.

Humidity increases water concentration outside the leaf.

Less water evaporates from the lower surface of the leaf.

Explain the effect of amount of chlorophyll on the rate of photosynthesis.

The more chlorophyll a leaf has, the more photosynthesis it can perform as it can absorb more energy.

name the 5 main tissues in a plant leaf

epidermal, palisade mesophyll, spongy mesophyll, xylem and phloem