Additional Biology Notes
- Created by: ErinKHennessey
- Created on: 08-06-17 16:45
cells, tissues and organs
an animal cell contains:
cell membrane
cytoplasm
nucleus
mitochondria
ribosomes
a plant cell contains:
chloroplast
vaucole
cell wall
cell membrane
mitochondria
nucleus
ribosomes
cytoplasm
structure and function
cell membrane - controls what goes in and out of the cell
cytoplasm - where chemical reactions takes place
nucleus - controls the activity of the cell and contains genetic material
ribosomes - where protein synthesis takes place
mitochondria - the site of aerobic respiration to break down glucose to create energy
chloroplasts - contain chlorophyll to absorb sunlight for photosynthesis
vaucole - contains cell sap and keeps the cell rigid for support
call wall - made of cellulose to support and strengthen the cell
a bacterial cell contains:
cell membrane
cell wall
flagella
DNA plasmid
circular DNA
slime capsule
Specialised cells
a cell containing a small amount of cytoplasm - more space for fat
a cell containing many mitochondria - provides more energy to reform pigment needed to let you see in colour
a cell with large surface area - greater uptake of mineral ions and water
a cell with a fatty myelin sheath - insulates neurone for faster nerve impluses
a cell with no nucleus - more space for haemoglobin to carry oxygen
Diffusion
diffusion is the spreading out of the particles in a gas or substance in a solution
the movement is from an area of high concentration to an area of low concentration
6 mark question about naming substances that diffuse into animal and plant cells:
animal cells:
during respiration,oxygen is being used and so will diffuse into the cells whilst carbon dioxide is being produced so will diffuse out of cells.
in digestion, glucose, fatty acids and amino acids (the products of digestion) will diffuse from small intestine into the bloodstream
water being absorbed back into the body through the large intestine
plant cells:
in the leaf, carbon dioxide will diffuse into the leaf through stomata whilst oxygen diffuses out. This is the reactant and product of photosynthesis
water being lost in leaves from transpiration
water being taken in from the soil into the roots
smallest to largest:
CELL - a group of cells make a tissue
TISSUE - a group of tissues make an organ
ORGAN - organs doing the same process makes up an organ system
ORGAN SYSTEM - a process such as digestion
photosynthesis
the equation for photosynthesis:
carbon dioxide + water -----sunlight------ oxygen + glucose
how do plants use this glucose?
converted into starch for storage
to make oils
to make proteins
energy for respiration
Test for starch is to put iodine on as iodine will go from orange to black in the presence of starch
Use of glucose in plants
plants use glucose in a number of ways such as:
stored or converted into starch which is used as a back up energy source
to make amino acids and proteins
to make fats and oils
respiration
growth and reproduction
the limiting factors of photosynthesis
the effect of light intensity…
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