Support system in animals (10)

Anything that supports the body. It gives the body shape and support, allows locomotion and protection.

Hydrostatic, exoskeleton, endoskeleton.

Skeleton in which support is provided by fluid under pressure in the body cavity. Water cannot be compressed – causes a firm, flexible shape. Animals have muscles in body wall that pushes against liquid to move. E.g. jellyfish, earthworm.

Advantages: -Requires relatively little muscle mass to move compared to exoskeleton and endoskeleton. -Highly flexible body shape -Allows for passive diffusion of important substances (oxygen, water, into the organism Disadvantages: -Only effective in water or moist environment. -Limits body size -Slower movement than animals with exoskeleton or endoskeleton.

Skeleton found on the outside of the body of an animal. Provides protection for internal organs, support for the body and a structure to which muscle can attach. Still has joints for movement. E.g. insects, snails.

Advantages: -Protects organism against predation and injury to soft tissue. -Prevents organism from drying out. Disadvantages: -Limits body size, not as effective for larger animals. -Needs to be shed as exoskeleton cannot grow as the arthropod grows -Vulnerability to predation when it moults.

Skeleton lying entirely within the body of an animal. Support for the body and locomotion.

Advantages: -Bone grows as animal grows. -Repairs itself when broken and adapts to external stresses. -Provides attachment points for skeletal muscle. -Stores calcium and phosphates. -Provides denser and stronger structure. -Supports variety of body sizes. Disadvantages: -Does not provide protection as an exoskeleton for soft body tissue. -Body is fairly heavy and movement is energy intensive.

Light, but strong non-living material that forms the exoskeleton of arthropods. Shed by epidermis.

Periodic loss of the exoskeleton in arthropods. They moult in order to grow.

Only use legs for locomotion.

Stiff bristles made of chitin.

Fluid-filled body cavities of animals.

Early stage development.

Support, movement, protection, storage of mineral salts, hearing, production of red blood corpuscles.

Long cylindrical bones that contain marrow. They are longer than they are wide.

Parts of the bone that form surfaces of a joint.

In textbook page 142.

Skull, vertebral column, ribcage.

Opening in the base of skull through which the spinal chord closes.

Two bumps on either side of the foramen magnum which articulate (form a joint) with the atlas.

Protects the brain Protects sense organs Assists with chewing, breathing, talking etc.

Cervical 1-7 Thoracic 1-12 Lumbar 1-5 Sacrum Coccyx

Prevents friction, shock absorber, allows some movement between them.