Biology Chapter 24

Invertebrate

animal without a backbone

Exoskeleton

external skeleton

Endoskeleton

internal skeleton

Vertebrate

animal that has an endoskeleton and a backbone

Hermaphrodite

animals that produce egg and sperm in the same animal body

Zygote

fertilized egg cell

Internal Fertilization

when the sperm and egg combine inside the animal's body

External Fertilization

when the sperm and egg combine outside the animal's body

Anterior

head end

Posterior

tail end

Dorsal

surface, backside

Ventral

surface, underside or belly

Filter Feeder

when an organism gets its food by filtering small particles of water

Sessile

organism that attaches to and stays in one place

Big Idea:
Animal organization is determined by body ______ and ____________.

type
structure

Animals are ______________ so they must feed on other organisms.

heterotrophic

Over 95% of animals are _____________ meaning they don't have backbones.
- bodies of many invertebrates are covered with a hard outer covering called an ________________
- If an animal has an endoskeleton and a backbone it is called a _____________

invertebrates
exoskeleton
vertrebrate

Animal cell structures do not have ____ walls.

cell

A group of cells that are specialized to perform a unique function are called _______.

tissue

Animal motion is more complex and ________ than organisms in any other kingdom. This is due to the fact that their _______ and ________ tissues are better developed than those of lesser organisms.

faster
nerve
muscle

Most animals reproduce ___________. This can occur in the form of ________ fertilization or ___________ fertilization.

external
internal

Symmetry describes the similarity or ________ among the structures of an organism

balance

Asymmetry describes an ____________ shaped organism with no balance to its body structures. _______ fall into this category.

irregular
coral

Radial Symmetry is an animal that can be divided along a central axis into roughly equal halves. __________ and jellyfish are in the category.

Starfish

Bilateral Symmetry means these organisms can be divided into mirror image halves only along one plane though their central axis. ______, fish and ___________ fit this description.

Birds
mammals

Cephalization: Animals that are bilaterally symmetrical also have an ________ (head end) and a _________ (tail end). These organisms also tend to have a _______ (back side) as well as a _______ (underside)

anterior
posterior
dorsal
ventral

Segmentation: segmented animals can be put together of a series of connected links. ______________ and _________ are good examples of segmented animals.

earthworms
insects

Sponges and Cnidarians are the most _______ of animal species. Without the benefit of tissues, organs or symmetry, they are able to ____, _____ and ___________.

basic
grow
feed
reproduce

The body structure of a sponge shows little if any ____________. ____ layers of independent cells with a jelly-like substance between them accomplish all the life functions of sponges.

Symmetry
Two

Sponges feed by drawing water in through pores on their surface, _______ food particles out and expelling water and wastes out though the central __________.

filter
osculum

Sponges __________ both sexually and asexually.

reproduce

Sponge ______ move through the water using cilia but they quickly attach themselves to some surface and become _______ adults.

larvae
sessile

Cnidarians include ___________, ________ and ___ ___________. Most of these species are _______.

jellyfish
corals
sea anemones

Like Sponges, cnidarians have one body opening and two layers of cells. They possess ________ symmetry and can _______ or be sessile.

radial
float

Cnidarians tentacles are armed with stinging cells named ____________ that hold a coiled tube containing poison and barbs.

nematocysts

After capture by the nematocysts and tentacles, prey is brought to the mouth of the _________________ cavity for digestion.

gastro-vascular

True or False:
All animals are heterotrophic.

true

True or False:
An endoskeleton must be shed before the animal possessing it can grow larger.

false

True or False:
When an individual organisms can produce both eggs and sperm it is called a hermaphrodite.

true

What is the name given to an organism with an endoskeleton and backbone?

vertebrate

Why must external fertilization in animals always occur in water?

the sperm must swim to the egg

If you are asked to lay an organism on its dorsal side, what kind of symmetry does the organism have?

bilateral symmetry

In jellyfish, the medusa stage follows the _______ stage.

polyp

The main advantage animals gain from segmentation is the ability to _____ in complex ways.

move

Specialized cells called _______ cells bring water into the body of a sponge.

collar

The zygote of a sponge develops into a _______ that is free swimming.

larva

If the trigger part on a cnidocyte is damaged or missing, the _____________ cannot be released.

nematocyst