Biology Flashcards
Name 3 differences between plant and animal cells
Plants have a cell wall, chloroplasts, large vacuole and rectangular shape
What do plant and animal cells both have
Cell membrane, nucleus and cytoplasm
Where do chemical reactions in cells take place?
Cytoplasm
What contains the genetic information in a cell?
nucleus
How are root hair cells adapted?
large surface area for absorption
How are palisade cells adapted?
Lots of chlorophyll and rectangular shape so no gaps between them
What is diffusion?
Movement of particles from high concentration to low down a concentration gradient
How do substances move in and out of cells?
Diffusion through cell membrane
What is osmosis?
Movement of water from dilute solution to concentrated solution
How does water enter cells?
Osmosis
What is the symbol equation for photosynthesis?
6CO2 + 6H2O = C6H12O6 + 6O2
What happens to the glucose made by photosynthesis?
Used in respiration, transport or stored as starch
Why do we use aquatic plants for photosynthesis experiments?
To see the bubbles given off
What is chlorophyll used for?
Trap sunlight for photosynthesis
What allows gases in and out of a leaf?
Stomata
Why are nitrates taken in through roots?
Make amino acids for growth
Why is magnesium taken in through roots?
To make chlorophyll
What does xylem transport?
Water
What does phloem transport?
Sugar
Describe the pathway of water through a plant from soil to the air
In through root hairs, into root, then into xylem which takes it up through the stem to the leaf and out through stomata
What is transpiration?
Evaporation of water from the xylem into the mesophyll layer
What speeds up transpiration?
Hot day, dry day (less humid) and windy day
What is gravitropism?
Plants growing towards or away from gravity
What is phototropism?
Plants growing towards or away from light
What is the name of the plant growth hormone and where is it made?
Auxin - tip of the shoot
How does a plant grow towards light?
Auxin collects on dark side and makes those cells grow faster so plant bends
Why do roots grow down?
Gravity pulls auxin to the bottom of the root which stops those cells at the bottom growing and so it bends down
Where is pollen produced?
Anthers
What is pollination?
Transfer of pollen from an anther to a stigma
What is fertilisation?
When the nucleus of a pollen fuses with the nucleus of an ovule
How can you tell a plant is animal or insect pollinated?
Bright colours, scent, nectar and hooks on pollen grain
How can you tell a plant is wind pollinated?
Anthers hang out of the flower. Pollen grains are small, light and smooth
What is the source of energy in food chains?
Sun
What always starts a food chain?
Producer (plant)
What are the animals called?
Consumers
What is the position of an animal in a food chain or food web called?
Trophic layer
What happens at each stage of a food chain?
Energy is lost (so most are only 4 trophic layers)
How is energy lost at each stage of a food chain?
Not all parts eaten, some is egested, some is excreted, the animals use energy to move
What live on dead or decaying matter?
Decomposers
What happens in eutrophication?
Fertilisers wash into rivers, river plants grow, ones at surface grow so much they block the sun so ones at bottom die. Decomposers eat the dead plants so multiply and use all the oxygen up when they respire, this means fish die
What are the seven life processes?
Movement, respiration, sensitivity, growth, reproduction, excretion, nutrition
