P7 SCIENCE LESSON NOTES.pdf

SCIENCE LESSON NOTES FOR P.7 - Hydrostatic skeleton - Exo skeleton - Endo skeleton 1. Hydrostatic skeleton. • This is a type of skeleton where the body of an organism is filled with a liquid under pressure. • Organisms with hydrostatic skeleton include; - Earth worms. - Slugs. - Snail - Intestinal worms - maggots 2. Exo skeleton. • This is a type of skeleton found outside the body of a creature. • Exo skeleton is common with all arthtopod e.g. house flies, grass hoppers, mosquitoes spider , crab e.t.c • Exo skeleton provides support and protection to soft parts of an centipede arthropod etc. 3. Endo skeleton. • This is a type of skeleton found inside the body of an organism. • Organisms with endo skeleton include, man( human beings) cows, goats e.t.c • Endo skeleton is made of bones and cartilages. The structure of the human skeleton BONES • Bones are hardest tissues found in animals with back bones (vertebrates). • Bones contain living cells which are supplied with food and oxygen by blood vessels. • Bones are made from mineral salts and proteins. MUSCULAR AND SKELETAL SYSTEM Definition of the skeleton. • A skeleton is a frame work of bones in the body. • A skeleton is a structure that supports the body Types of skeletons They include; For more lesson notes, please visit www.freshteacheruganda.com • Mineral salts include calcium and phosphorus. Types of bones Bones are classified according to their shapes as: For more lesson notes, please visit www.freshteacheruganda.com - K