Animalia Kingdom

Question 1

Briefly describe Animal’s period of embryonic development

Answer 1

Progresses from blastula – gastrula – germ layers – tissues (cells become
specialized as tissues form)

Question 2

Briefly describe the three layers of tissues that become established during
early embryonic development

Answer 2

Ectoderm
 Surface epithelia (skin) and nervous system

Mesoderm
 Muscles, connective tissues (incl. blood), skeleton, kidneys, circulatory
and reproductive organs

Endoderm
 Gives rise to the intestine and associated organs

Question 3

Briefly describe the ACEOLOMATE

Answer 3

the ACOELOMATE has no body cavity (solid mesoderm) Best e.g.- flatworms

Question 4

Briefly describe the PSUEDOCOELOMATE

Answer 4

PSEUDOCOELOMATE (not “false” – very real!)

Body cavity, fluid-filled, between the mesoderm and endoderm
(contains gonads, excretory tubules)

Best e.g. nematodes (roundworms)

Called haemocoel in some.

Question 5

Briefly describe the COELOMATE

Answer 5

Occurs entirely within the mesoderm

Best e.g. annelids, echinoderms and chordates

Question 6

What is a Coelum

Answer 6

Coelom significance:

A coelom (body cavity) provides:

Space for organs to grow and move

A hydrostatic skeleton for movement

Circulation of nutrients and waste

Cushioning of internal organs