ORGANELLES: A small structure found in the cells like (NUCLEUS).
Different organelles form up a cell.
SPECAILISED CELLS IN PLANTS:
XYLEM CELLS: These are small cells that carry up water to the stem.
LEAF PALASIDE CELLS: Contain a lot of chloroplast for photosynthesis.
ROOT HAIR CELLS: They are long and thin to absorb water from the soil.
SPECIALISED CELLS IN ANIMALS:
RED BLOOD CELLS: they have a substance that contains oxygen.
MUSCLE CELLS: Can shorten to move bones.
EGG CELLS: Have a store of food in the cytoplasm.
SPERM CELLS: Have a tail to swim to the egg.
NERVE CELLS: Carry messages around the body.
SINGLE CELLS:
They are unicellular.
AMOEBA:
It lives in ponds and ditches. It moves by changing its shape. It pushes out pseudopodia. It feeds on smaller things like bacteria. They get taken into a food vacuole. They add an enzyme to break down the food. Oxygen is dissolved into the water around AMOEBA. It gets inside by diffusion. The waste substances diffuse out of Amoeba by diffusion as well.
MANY CELLS:
They are multi cellular.
SPIROGRYA:
It lives on the surface of a pond. The cells are all joined together by filaments. It makes its own food by photosynthesis because they contain a chloroplast.
CELL SIZE: As the surface area: volume ratio increases the cell size decreases. This means multicellular cells have a slower rate of diffusion.
HOW TO FIGURE OUT THE SURFACE AREA: VOLUME RATIO IS?
1cm 2cm 3cm
A B C
- SA : VR
1x 1x6=6:1X1X1= 1cm
6:1 therefore 6 divided by 1 = 6
- SA : VR
6x2x2=24:2x2x2=8cm
24:8 therefore 24 divided by 8 = 3
- SA : VR
3x3x6=54:3x3x3=27cm
54:27 therefore 54 divided by 27 = 2
TISSUES:
A group of similar cells make up tissues.
ORGANS IN AN ANIMAL:
A group of similar tissues make up an organ.
Cells Tissues Organs Organ system
ORGAN SYSTEMS:
DIGESTIVE SYSTEM: STOMACH, GULLET, INTESTINES.
NERVOUS SYSTEM: BRAIN, SPINAL CORD, NERVES.
EXCRETORY SYSTEM: BLADDER, UTERERS, KIDNEYS.
CIRCULATORY SYSTEM: HEART, CAPILARIES, ARTERIES, VEINS.
REPRODUCTIVE SYSTEM: OAVRIES, OVIDUCT, UTERERS.
RESPIRATORY SYSTEM: LUNGS, WINDPIPE.
PLANT ORGANS:
Palisade cell Palisade tissue Organ Organism
Palisade cells make up palisade tissues.
And a palisade tissue is found in a leaf.
THE FIVE KINGDOMS:
THE ANIMAL KINGDOM
VERTABRATES (HAVE A BACKBONE):
REPTILES (Dry scaly skin)
AMPHIBIANS (breed in water, soft moist skin)
MAMMALS (hair or fur) the female mammals give their young milk by mammary glands.
Mammals are warm blooded.
BIRDS (feathers and wings)
FISH (scales, fins and gills). They breathe in oxygen with their gills.
INVERTABRATES:
WORMS:
FLAT WORMS (flat with mouth on one end)
ROUND WORMS (long, they have a thread like body)
SEGMENTED WORMS (their body divide into segments).
CNIDARIANS (they have a sac like body, they have tentacles)
MOLLUCSC (have a shell and a muscular foot)
ENCHINODERMS (spiny skins and have a pattern of 5 parts).
ANTHRAPODS:
INSECTS (have a 3 part body, 3 pairs of legs and 2 pairs of wings)
CRUSTACEANS (chalky exoskeleton)
MYRIAPODS (have a segmented body and have many legs)
ARACHNIDS (body in 2 parts, 4 pairs of legs).
THE PLANT KINGDOM
PLANTS:
FERNS (They have strong stems, roots and leaves. They make spores).They have xylem in them.
CONIFERS (needle like leaves. Their seed are made inside the cone). They make female and male cones instead of flowers.
FLOWERING PLANT (They have flowers which make seeds).
MOSSES AND LIVERWORTS (no proper roots or cells, they make spores and lose water)
THE PROTISTS:
They are unicellular (Protists) and they can be (algae) when they are multicellular.
FUNGI:
(Most fungi are saprophytes).
They make spores. They are made up of thin threads called hyphae.
BACTERIA:
They haven’t got a proper nucleus and they are microscopic.
PARASITES: When something lives of another organism
