Biology2 Y9 Flashcards
The process in which plants manufacture carbohydrates from raw materials by using energy from light.
Photosynthesis
Green plants make the carbohydrate ———– from the raw materials —————— and water.
At the same time, ———— is made and released as a waste product.
The reaction requires ———- which is obtained by the pigment —————– trapping light from the sun.
Green plants make the carbohydrate glucose from the raw materials carbon dioxide and water.
At the same time, oxygen is made and released as a waste product.
The reaction requires energy which is obtained by the pigment chlorophyll trapping light from the sun.
The raw materials required for photosynthesis…
Carbon Dioxide and Water.
Note: Light energy is not a substance and therefore cannot be a raw material.
The chemical reaction in cells that uses oxygen to break down substances such as glucose to release energy is…
Aerobic respiration
————— and ————— are produced as waste products in respiration.
Carbon dioxide and Water are produced as waste products in respiration.
Where in the plant cells does aerobic respiration occur?
Mitochondria.
A reactant or variable that stops a reaction from going faster
A limiting factor.
Roots anchor a plant and absorb —– and ————-.
Roots anchor a plant and absorb Water and Mineral salts.
Describe how water and mineral salts are absorbed and moved around a plant.
Roots have root hair cells that have a large surface area that can absorb water and minerals by diffusion.
Stems have xylem vessels made of xylem cells.
It’s a hollow tube that can transport water and dissolved mineral salts up the stem.
———— is the process by which water leaves the leaf.
Transpiration.
Explain how roots are adapted to their function.
- Being branched and spread out, allowing it to get water from a large volume of soil
- Roots have root hair cells that have a large surface area so they can quickly absorb water.
Explain how stems are adapted to their function.
Stems have vessels to transport water and are adapted to this by having hollow tubes with no ends.
Where are the xylem vessels are found?
A- Stems
B- Roots
C- Roots and Stems
C- Roots and Stems
True or False: Xylem vessels are long tubes made of chains consisting of dead xylem cells.
True.
The tubes made of living phloem cells that transport dissolved substances (such as sugars) around the plant are called
Phloem Vessels/Tissues
How do roots get glucose for respiration?
Through the phloem vessels.
What is the function of the phloem vessels?
They carry glucose to all parts of a plant in the form of sugars dissolved in water.
How do roots get its:
A- Glucose
B- Oxygen
C- Water and Mineral Salts
A- Glucose. Through phloem vessels in the form of a sugar solution
B- Oxygen. From soil
C- Water and Mineral Salts. From soil
How does the chemical energy stored in the glucose get released?
Aerobic Respiration
How have Mangrove plants adapted to living in waterlogged areas?
By having special roots called pneumatophores that poke up above the surface of the water to get air.
Why do root cells need oxygen?
For respiration
A limiting factor is a variable that…
A- Speeds up the rate of respiration
B- Slows down the rate of respiration
B- Slows down the rate of respiration
How do plants lose water?
By transpiration - when the water leaves the leaf.
Transpiration is the evaporation of water followed by diffusion through the stomata.
Plants lose water through
A- Only evaporation
B- Only diffusion
C- Evaporation and diffusion
C- Evaporation and diffusion
in aquatic plant what is the test for carbon dioxide ?
pH indicator such as hydrogencarbonate indicator
in the experiment of measuring phtosynthesis what do we need to use sodium carbonate?
to provide extra carbon dioxide in the water
Investigating the effect of changing light intensity on the rate of photosynthesis
Please review graph in page 23
why plants need water?
for phtosynthesis
keeping leaves cool and filling up cells to keep them expanded and firm
a tiny hole in a leaf through which gases can diffuse into and out of the leaf.
Stoma
stomata
in the Light intensity investigation
https://quizlet.com/Biology-Creator-QA/light-intensity-investigation-plant-structures-and-their-functions-biology-gcse-91-s8lpd55
https://quizlet.com/Biology-Creator-QA/plant-organisation-plant-structures-and-their-functions-biology-gcse-91-s8lpdig
https://quizlet.com/Biology-Creator-QA/photosynthesis-plant-structures-and-their-functions-biology-gcse-91-s8lpcw8
How leaves are adapted for their function?
- large surface area for trapping light.
- inside a leaf thre are different layers of tissue epidermis cells produce waxy layer ( cuticle) to stop the leaves losing too much water
- Palisade cells are adapted to their function by containing lots of chloroplasts where phtosynthesis occurs
- leaves have stomata shut at night and open when it is light allowing carbon dioxide enter and leave the leaf. gas exchange
- plants lose water and oxygen through stomata
Excess energy stored and ready for use to build cell membranes.
Starch
Glucose
Fats
Oils
Fats
Used in resperation to create energy for the plant.
Oil
Protein
Glucose
Starch
Glucose
Used to make proteins which are used for growth and repair.
Protein
Nitrogen
Glucose
Oil
Nitrogen
is turned into lipids for storing in seeds. Sunflower plant seeds contain oil, oil is attractive to some animals for pollination.
Oils
Fats
Glucose
Protein
Oils
is used for strong cell walls
Oils
Fats
Glucose
cellulose
cellulose
stored in roots, stems and leaves, ready for use when photosynthesis isn’t happening, like in winter.
Starch
used for making enzymes and for growth and repair.
Protein
describe how gas exchange happens in plants
Gas exchange happens in leaves
the leaf has small holes called the stomata which open and closes by guard cells. it opens when there is light and close at night to allow gases in and out . carbon dioxide for example gets into the cells by diffusion which happes close to the surface of the leaf.
describe how water is lost from a plant
water loss in plants happens in the leaves through a process called traspiration . traspiration is evaporation of water followed by diffusion through stomata
explain how the features of the leaves are adaptation for photosynthesis?
leaves have Palisade cells that are adapted to their function by containing lots of chloroplasts where photosynthesis occurs. palisades are close to the surface of the leaf.
gas exchange happnes in the leave through stomata. carbon dioxide which is needed for photosynthesis, are allowed in the stomata and gets into the cells by diffusion.
How do you perform the Benedict’s test?
1) Add Benedicts solution to the food to be tested.
2) Boil
Which test do you use for Starch?
Iodine test
How do you perform the Biuret test.
1) treat aqueous sample with an equal volume of 1% sodium hydroxide followed by a few drops of blue aqueous copper(II) sulphate.
What is the positive result of the Benedict’s test?
blue → brown.
What is the positive result of the Iodine test?
brown → dark blue
What is the positive result of the Biuret test?
solution turns purple
test for sugars?
benedict’s test
test for starch?
iodine solution
test for proteins?
biuret test
test for lipids?
Ethanol and water
benedicts test colour change?
blue to green, yellow or red
iodine solution colour change?
brown/yellow to blue/black
biuret test colour change?
blue to pink/purple
Lipid change
Cloudy for positive, clear without
the process by which a dormant seed begins to sprout and grow into a seedling under the right growing conditions
germination
a type of insoluble carbohydrates found in plants
starch
Recall the need for different resources in a seed as it germinates
Plants are selectively bred by humans for development of many characteristics
selective breeding
Selective breeding is also known as artificial selection
needed to make amino acids
nitrates
is needed to make chlorophyll
magnesium
is needed to help plants absorb from the soil
Potassium
Explain ways farmers use to increase food production
fertilisers - fertilisers increase the amount of key nutrients in the soil for crop plants, meaning that they can grow larger and are more healthy, which increases yields
Pesticides - these kill insects or fungi that damage crops
herbicides : these kill weeds – plants that compete with crops
producing new varieties of plants: these have improved characteristics
cross-breeding
different varieties are bred with each other to produce offspring thathave the characteristics of both breeds
label the following diagram
Plants that live in hot dry environment have thicker cuticles
To prevent uncontrolled water loss
At night when there is no photosynthesis most plants close their stomatas . explain why
to reduce water loss
plants that live in hot dry climates often have rolled-up leaves explain why
to reduce the surface area of evaporation
Stomata are found…
on the top side of leaves.
on the bottom side of leaves.
in the vegetable aisle.
on the bottom side of leaves.
Xylem tubes are responsible for transporting…
Sugar
Water
Food and water
Water
Transpiration is affected by an increase in…
temperature and light.
temperature and air movement.
temperature, light and air movement.
temperature, light and air movement.
If a plant weighs 150g on day 1 and 100g on day 3, the % change in mass would be…
-33.3%
25%
15%
-33.3%
Where in a plant does
photosynthesis occur?
nucleus
chloroplasts
cytoplasm
mitochondria
chloroplasts
What are the reactants for photosynthesis?
glucose + water
carbon dioxide and water
glucose and carbon dioxide
glucose and oxygen
carbon dioxide and water
Name the green pigment
found in plants.
chlorophyll
The correct equation for photosynthesis is…
carbon dioxide + water glucose + oxygen
What type of energy is required to activate photosynthesis?
kinetic
thermal
light
potential
light
A variegated leaf (similar to the one shown below) is tested for starch. What would be the expected results?
All of the leaf would turn black.
None of the leaf would turn black.
Only the green parts of the leaf turn black.
Only the white parts of the leaf turn black.
Only the green parts of the leaf turn black.
The leaf has a broad
surface because…
it has a large surface area to absorb light.
The limiting factors of
photosynthesis are…
light, carbon dioxide and temperature.
The graph below shows the effect of what limiting factor on photosynthesis?
temperature
The ideal conditions for photosynthesis can created in…
warehouses.
factories
fields
greenhouses
greenhouses.
Name two processes that return carbon dioxide to the atmosphere
- respiration
- combustion
Name one human activity that affects carbon dioxide levels in the atmosphere
deforestation
Name two ways that carbon is stored in the carbon cycle.
- fossil fuels
- as carbon dioxide dissolved in water/the ocean
