BIO 110 Chapter 10

All animals share a common set of a features, the most recognizable one is that they are ______

heterotrophs

Phylum

a level of classification in biology that groups organisms based on their body structure and development

Bilateral symmetry

an organism that can be cut in half and has mirror-image halves on either side of a central axis.

Radial symmetry

an arrangement of the body parts of an organism like pieces of a pie around an imaginary central axis

The vast majority of animals are _______

invertebrates

______ represent the descendants of the earliest branch on the animal evolutionary tree, and have the simplest anatomy of any animal

sponges

Why are sponges considered animals?

they have specialized cells that perform specific functions

________ include sea anemones, hydras, corals, and jellies

cnidarians

A mobile form of a cnidarian that floats mouth down

medusa

A stationary form of a cnidarian that are fixed to larger objects

polyp

Flatworms can be found in _____ habitat, most of them have a ________ ____ with a single opening that acts as both mouth and anus

any, gastrovascular cavity

A gastrovascular cavity serves as both the entrance and exit for ____

food

What kind of evolutionary adaptation do annelids display?

segmentation

What does segmentation mean?

it is the division of the body into a series of repeated segments that allow for greater flexibility and more complex movements

Roundworms have a complete digestive tract with two openings, the _____ and the _____

anus, mouth

What is the difference between a nematode and an annelid?

a nematode has a complete digestive tract with two separate holes while an annelid only has one

A phylum of soft-bodied animals, many of which are protected by a hard shell is called _____

mollusks

All mollusks have what type of symmetry?

bilateral

All _____ have two calcium-containing shells connected by a hinge

bivalves

______ are the most numerous group of mollusks, being found in salt/fresh water and land habitats

gastropods

ALL ____ have ______ bodies, a tough ______, and several jointed appendages that perform specific functions such as walking, feeding, or swimming

arthropods, segmented, exoskeleton

Most arachnids are…

terrestrial carnivores that paralyze their prey

Most _______ live in water. Many of them (shrimp, lobster, crabs) are valuable food sources

crustaceans

To grow in size, an arthropod must build a new ______ and then molt, shedding its old one

exoskeleton

An arthropod is divided into three body segments which are…

abdomen, thorax, head

_______ outnumber all other animals combined, by far.

insects