Animals are multicellular organisms that feed on other organisms have a nervous system usually move around can be divided into: 1) INVERTEBRATES (have no backbone) 2) VERTEBRATES (have a backbone)
1) CNIDARIA or (COELENTERATA) simple sac-like body with a single opening surrounded by tentacles armed with stinging cells mouth/anus tentacle
CNIDARIA or (COELENTERATA) sea coralanemone jelly fish hydra
2) FLATWORMS (PLATYHELMINTHES) body is elongated and flatTapeworm inside Tapeworm head with intestines. hooks & suckers.
3) NEMATODES (ROUNDWORMS) have a long thread-like body, round in cross-section some live in the soil, but many Nematode in soil. are plant or animal parasites Nematodes damageNematodes inside a root. potatoes.
e.g. Ascaris & pin worms (live in human gut) Ascaris: 25-40 cm long.Ascaris block intestines. Pin worms
4) ANNELIDS (segmented worms) long body divided by rings into a series of segments have a digestive tract with a mouth and anus earthworm leech ragworm
7. Spiracles on the thorax and abdomen. Spiracle leads to the spiracle tracheal system.
Functions of the exoskeleton1. It is hard and so protects the insect from damage attack of microbes.
Functions of the exoskeleton2. It is covered by a waxy layer and so makes the insect waterproof. Thus insects can live in dry places.3. It provides a place where muscles can be attached.
Development of insects Metamorphosis: is when an animal changes its form TWO types of metamorphosis in insects: Complete metamorphosis : 4 stages Incomplete metamorphosis : 3 stages
Complete metamorphosis is when : an insect undergoes a complete change FOUR stages in life cycle: larva larva pupa e.g. housefly mosquito egg adult butterfly
The larva & adult feed on different types offood. How is this an advantage to the insect? Adult feeds on nectar. Larva eats grass. Avoid intraspecific competition. Occupy different niches.
Incomplete metamorphosis is when: the insect develops gradually THREE stages in life cycle: e.g. grasshopper beetles adult egg ladybirds nymphsInstars:stages between moults
A nymph looks exactly like an adult but has no wings nymphsadult
Why do you think that nymphs & adults compete with each other? Feed on the same type of food and occupy the same niche. Grasshopper nymphs.Both have biting mouthparts.
Ecdysis or Moulting is the removal of the exoskeleton from time to time happens to let the insect to grow happens in the: larva nymph stage BUT not in the adult
The Vertebrates have: a vertebral column extending to form a tail an internal skeleton, usually made of bone five classes: 1. Fish 2. Amphibians A shift from 3. Reptiles an aquatic to 4. Birds a terrestrial 5. Mammals habitat.
Question: SEP, 2004Give biological explanations for each of thestatements:Birds have hollow bones. (2)To be light and so can fly.
Question: MAY, 2009Give the biological explanation of each of thefollowing statements. Birds are well adapted to move through the air. (5)
Question: MAY, 2009 1. Have wings to fly. 2. Skeleton is lightweight due to hollow bones. 3. Have a beak instead of teeth to be lightweight. 4. Feathers cover the streamlined body to reduce air resistance. 5. Tail helps to steer and brake.
Question: SEP, 2012Hawks are bird species commonlyfound in desert biomes. Explain whysome of the largest feathers areattached to the wing. (2)Large feathers are needed toprovide a large surface area toflap the wings to provide lift.
MAMMALS have hair young ones: usually develop inside the mother
are fed on milk produced by the mammary glands
MAMMALS have: sweat glands whiskers an outer ear a diaphragm
Three subgroups of mammals:-1. Egg-laying mammals platypus spiny ant-eater
2. Pouch mammals (marsupials) Young kangaroo suckling milk.
The vertebrate classes can be:-1. POIKILOTHERMIC (cold-blooded) - cannot regulate their body temperature - fish, reptiles & amphibians2. HOMEOTHERMIC (warm-blooded) - can regulate their body temperature - birds & mammals [NEVER USE cold and warm blooded in your answers].
Fish, reptiles & amphibians are: get heat from their surroundings Convection Radiation Conduction
Birds & mammals are: get heat from inside their body by: respiration muscle contraction
Question: MAY, 2010Which property of birdsallows them to incubate eggs? (2) Have feathers that makes them keep a constant body temperature. They are homeothermic.
Advantages of being endotherms:animal is active all the time and all year round: so can escape predators search for food more efficientlyimmune system works well
Question: SEP, 2006Give ONE structural difference to distinguishbetween:a) an insect and an arachnid (1)Insect: 3 body parts/ 6 legs/ compound eyesArachnid: 2 body parts/ 8 legs / no compound eyesb) a fish and a reptile (1)Fish: moves by fins / has gills to breatheReptile: moves by legs / lungs to breathe
Question: SEP, 2007Give THREE characteristics of EACH of thefollowing groups of organisms:a) annelids; (3) long body divided by rings into a series of segments have a digestive tract with a mouth and anus move by bristles
Question: SEP, 2007Give THREE characteristics of EACH of thefollowing groups of organisms:b) arthropods. (3) segmented animals body is covered by an exoskeleton which is shed by moulting have jointed limbs