Download Animal Body Systems

Bell Ringer
WHAT IS A
VERTEBRATE?
Animal Body Systems
Objectives
 Summarize the functions of digestive, circulatory,
nervous, skeletal, and excretory systems.
 Compare a gastrovascular cavity with a one-way
digestive system.
 Differentiate open and closed circulatory systems.
 Distinguish asexual and sexual reproduction
Digestion
 Single celled organisms and sponges digest their
food within their cells, all other animals digest food
extracellularly.
 Simple animals like hydras and flatworms have a
gastrovascular cavity with only one opening.
Respiration
 In simple animals, oxygen gas and carbon dioxide
are exchanged directly by diffusion.
 Uptake of oxygen, respiration, can take place across
a moist surface.
 Aquatic animals respire with gills.

Thin projections filled with blood vessels.
Gills
 Each gills has a double row of tiny projections called
gill filaments.
 These are rich in blood vessels, which have a large
surface area.
 Fish take in water through their mouths and move it
over the gill filaments.
 Gas exchange occurs
Circulation
 Oxygen must be transported to cells in the body. The
circulatory system transports blood.
Circulation
 Open Circulatory System – heart pumps fluid
containing oxygen and nutrients through a series of
vessels than into a body cavity.
 Closed Circulatory System- heart pumps blood
through a series of vessels.
Nerve Impulses
 Nerve cells (Neurons) carry messages in form of
electrical signals
 What is an open circulatory system?
 Bilaterally Symmetrical animals have clusters of
neurons called ganglia.
 Complex organisms have various structures
associated with ganglia.

Example: Eyes
Support
 Hydrostatic skeleton- skeleton that consists of water
that is contained under pressure in a closed cavity.
 Muscle forces exerted against the hydrostatic
skeleton aid in movement.
 Exoskeleton- rigid external skeleton that encloses
the whole animal.
 The muscles of animals with an exoskeleton are
attached to the inside of the skeleton. Exoskeletons
also protect the soft internal organs.
 Endoskeleton- composed of hard material, such as
bone, imbedded in an animal.
 Muscles attached to the endoskeleton contract and
relax to help the animals move.
Excretion
 Excretion- removal of waste by cellular metabolism.
 Waste leaves the cell by crossing the cell membrane.
 Some waste products are poisonous and must be
removed from the organism.
 Example: Ammonia
 In some aquatic animals ammonia is eliminated by
diffusion through the skin.

Results in loss of water.
 Eliminating of metabolic wastes is linked to
maintaining the bodies water balance.
 In mammals, kidneys filter fluid from the blood. The
kidneys then concentrate the wastes filtered from the
fluid and excrete them as concentrated urine.
Reproductive Strategies
 Asexual Reproduction-reproduction that does not
involve the fusion of two gametes.
 A sponge reproduces by budding, or fragmenting its
body. Each piece that is fragmented develops into
another sponge.
Bell Ringer
 What organ filters our blood?
Asexual Reproduction
 Parthogenesis-a new individual develops from
unfertilized eggs.
Sexual Reproduction
 Sexual Reproduction-new individuals formed by the
union of male and female gametes.
 Gametes-sex cells
 Hermaphrodite-species of animal that has both
testes and ovaries.
 What would prevent against self fertilization?
 External fertilization-egg is fertilized outside of the
female’s body. Large gametes are released during
external fertilization.
 Internal fertilization-union of sperm and egg within
the females body.