Key Vocabulary Terms

Filter feeding - A way of getting food by straining it out of the water
Herbivore - an animal that cats plants
Carnivore - an animal that eats other animals
Secrete - form an release, or give off
Enzyme - a substance that speeds up chemical changes
Gastrovasular cavity - a digestive space with a single opening
Digestive tract - a tubelike digestive space with an opening at each end
Crop - the part of the digestive tract of some animals where food is stored
Gizzard - the part of the digestive tract of some animals that grinds food
Anus - the opening through which material that is not digested leaves the digestive tract

Key Concepts

There are many animals that use filter feeding to get food; sponges, barnacles, mollusks, whales, and many more.
Animals each have individual ways of feeding. Cicadas have mouthparts that pierce and draw up liquid. Dragonflies have mouthparts that cut and chew.
Animals must digest their food because molecules of fat, protein, and carbohydrates can not be used by cells for energy until they are broken down.
Each animal has an individual digestive space that works a little differently. For example, Cnidarans have a gastrovascular cavity, which is a hollow space with one opening, the mouth.
The digestive tract performs the function of storing ingested food, digesting it, and absorbing the nutrients.

Did you learn these Objectives?

Are you able to describe three main ways animals get food.
Can you explain the importance of digestion?
How do you tell the difference between a gastrovascular cavity and a digestive tract?

Investigation 6 "Studying Feeding in Hydras" (Optional, must complete 10 total investigations)

Key Concepts and Objectives

You will use your skills of observing, classifying, describing, comparing, making inferences, and drawing conclusions to determine what stimuli trigger feeding responses in a simple animal.
You will create a visual record the responses of different stimuli in order to determine the feeding responses to different stimuli.

Useful Internet Links

http://ebiomedia.com/gall/classics/Daphnia/daphnia_feed.html This site shows hydra feeding on a daphnea (water flee. It also has many other great images for those of you without a microscope this is a must.
http://www.sidwell.edu/sidwell.resources/bio/hd/index.html This site as a great set of picture taken through a microscope of a hydra feeding on a daphnia.

Respire - take in oxygen and give off carbon dioxide
Diffusion - the movement of materials from an area of high concentration to an area of low concentration
Circulatory - flowing in a circle
Open circulatory system - a system in which blood makes direct contact with cells
Annelid - a segmented worm or a worm whose body is divided into sections
Closed circulatory system - a system in which blood stays inside vessels at all times
Atrium - a heart chamber that receives blood returning to the heart (plural is atria)
Ventricle - a heart chamber that pumps blood out of the heart

Key Concepts

Gases are exchanged with the blood in different ways in different animals. For example, gases are exchanged through the body wall of a sponge, which is only two cell layers thick.
Insects respire by using a system of tubes which carry gases into every part of the body.
In an open circulatory system, blood leaves the vessels and makes direct contact with cells. In a closed circulatory system, blood stays inside vessels at all times.
In a a vertebrate heart, the atria receive blood that is returning to the heart.
Hearts may operate the same in different animals, for example the right ventricle of a bird send blood to the lungs that is the same as the human heart.

Did you learn these Objectives?

Key Concepts

Most sea invertebrates keep an internal water concentration equal to that of seawater so they do not have to pump water out of their bodies.
The flame cell on a flatworm collects excess water inside and pushes it via cilia into tube for excretion.
Freshwater fish maintain water balance by getting rid of excess water by excreting urine using their kidneys.
Land animals must limit water loss with a covering that stops or slows evaporation of water, for instance: land snails have a shell; insects a waxy layer; and reptiles, birds, and mammals have a watertight skin.
The breakdown of proteins is a problem for animals because ammonia, which is a by-product of protein digestion, is a poisonous waste material and must be eliminated.

Did you learn these Objectives?

Are you able to explain how animals maintain water balance in the sea, in freshwater, and on land?
Can you explain how animals excrete wastes?

Coordinate - work together
Hormone - A chemical signal that glands produce
Impulse - a message that travels along nerve cells
Neurotransmitter - a chemical signal that a nerve cell releases
Nerve net - a bunch of nerve cells that are loosely connected
Central nervous system - the brain and spinal cord
Peripheral nervous system - the nerves that send messages between the central nervous system and other body parts.
Cerebrum - the larges part of the brain that controls thought, memory, learning, feeling, and body movement.

Key Concepts

Hormones are secreted by glands, enter the bloodstream, and are pumped throughout the body by the circulatory system.
A neurotransmitter is a chemical signal that are set in motion by a nerve impulse; they move to nearby cells and bind with proteins, causing the impulse to move on to the next cell.
The nerve net is loosely connected nerve cells that coordinate responses and control activities in cnidarians.
The main parts of a vertebrate's central nervous system are centrally comprised brain and spinal cord, and the nerves in the rest of the body.
The folds in the cerebrum give more surface area, allowing for more nerve cells; the more nerve cells the vertebrate brain has, the more the animal is able to learn and remember.

Did you learn these Objectives?

Chapter Summary and Review

See page 140-141

Chapter 6 Review answers are