1 compare and contrast how do vertebrates differ from other chordates 2 review describe the seven...
TRANSCRIPT
1 Compare and Contrast How do vertebrates differ from other chordates
2 Review Describe the seven essential functions performed by all animals
Explain Why must waste products produced by metabolic processes be eliminated from an animal’s body
3 Classify A classmate is looking at a unicellular organism under a microscope and asks you if it is an animal- what do you answer and why
CH 25 INTRODUCTION TO ANIMALS25.1 What is an Animal
Characteristics of Animals
Heterotrophs Obtain energy by eating other organisms
Multicellular Bodies are composed of many cells
Eukaryotic Contain a nucleus and membrane-bound organelles
Lack cell walls.
Types of Animals
Invertebrates Chordates.
Invertebrates
Include all animals that lack a backbone, or vertebral column
More than 95 percent of animal species are informally called invertebrates
From dust mites to giant squid.
Chordates
Exhibit at some stage of life: Dorsal, hollow nerve cord Notochord Tail that extends beyond the anus Pharyngeal pouches.
Chordates
Hollow nerve cord runs along the dorsal (back) part of the body
Nerves branch from this cord at intervals.
Chordates
Notochord is a long supporting rod that runs through the body just below the nerve cord
Most chordates only have a notochord as embryos.
Chordates
All chordates have a tail that extends beyond the anus at some point in their lives.
Chordates
Pharyngeal pouches are paired structures in the throat region (pharynx)
Slits may develop to connect to outside of body for gas exchange (gills).
Most chordates develop a backbone, or vertebral column, constructed of bones called vertebrae
Vertebrates Chordates with backbones Fishes, amphibians, reptiles, birds, and mammals.
Animal Survival
Maintaining Homeostasis
Feedback inhibition or negative feedback System in which the product or result of a process
limits the process itself If you get too cold, you shiver, using muscle activity to
generate heat Thermostat in house.
Gathering and Responding to Information
Nervous system gathers information using receptor cells that respond to sound, light, chemicals, and other stimuli
Other nerve cells collect and process that information and determine how to respond.
Often respond to processed information by moving Muscle tissue contracts when stimulated by the
nervous system Muscles work together with some kind of a
skeleton.
Some invertebrates have only a loose network of nerve cells, with no real center
Other invertebrates and most chordates have large numbers of nerve cells concentrated into a brain.
Obtaining and Distributing Oxygen and Nutrients
All animals must breathe to obtain oxygen May use gills, lungs, or air passages.
All animals must eat to obtain nutrients Most animals have a digestive system that acquires
food and breaks it down into forms cells can use.
Animals must transport them to cells throughout their bodies by using some kind of circulatory system.
Collecting and Eliminating CO2 and Other Wastes
Animals’ metabolic processes generate carbon dioxide and other waste products, some of which contain nitrogen in the form of ammonia
Many animals eliminate carbon dioxide by using their respiratory systems.
Most complex animals have a specialized organ system for concentrating, processing, and eliminating other wastes, such as ammonia.
Circulatory system must collect wastes from cells throughout the body and then deliver them to the respiratory or excretory system.
Reproducing
Most animals reproduce sexually by producing haploid gametes
Many invertebrates and a few vertebrates can also reproduce asexually.