All animals depend either directly or indirectly on autotrophs for food.
100
What do most animals develop from?
From a zygote (a fertilized egg shell)
100
What is symmetry?
It describes how an animal's body structures are arranged.
100
What other characteristics do bilaterally symmetrical animals share?
They all develop from 3 embryonic layers (ectoderm, endoderm, and mesoderm)
100
What is an exoskeleton?
A hard covering on the outside of the body, they provide a framework for support.
200
What are autotrophs?
Organisms that make their own food.
200
What happens during fertilization?
It occurs when a sperm cell penetrates an egg shell, forming a new cell. (a zygote)
200
What is asymmetry?
When an animal has no shape. The animal will be irregular in shape.
200
Where are the inside organs found?
Inside the body cavities.
200
What is an invertebrate?
Animals that do not have a backbone.
300
How do animals digest food?
In some animals, digestion takes place within individual cells. In others, it takes place in an internal cavity.
300
What is the process of cleavage?
When a zygote divides by mitosis and cell division to form two cells.
300
What is radial symmetry?
An adaptation that enables an animal to detect and capture prey coming toward it from any direction. When an animal can be divided along any plane, through a central axis, into almost equal halves.
300
What are animals called that develop from the same 3 cell layers but do not have body cavities?
Acoelomate
300
What is an endoskeleton?
An internal skeleton.
400
What does heterotrophic mean?
Animals must consume or eat other organisms to get their energy and nutrients.
400
What is a gastrula?
A structure made up of two layers of cells with an opening at one end.
400
What is bilateral symmetry?
When an animal can be divided down its length, along one plane, into similar right and left halves.
400
What is a coelom?
A fluid-filled space that is completely surrounded by mesoderm.
400
What three things can a endoskeleton be made of?
Calcium carbonate, cartilage, and bone.
500
If an animal ingest something, what else must happen?
They have to digest it.
500
What is mesoderm?
The third cell layer found in the developing embryo between the ectoderm and the endoderm.
500
Anterior? Posterior? Dorsal? Ventral?
Head end, tail end, upper surface, lower surface.
500
What is a pseudocoelom?
A fluid-filled body cavity partly lined with mesoderm.