ZoologyAn Introduction

Zoology

• Study of animals• In this class- Important Kingdoms-

Protista- some animallike organismsconsidered to be evol.

precursors to animalsANIMALIA- are ANIMALS

Kingdom Protista

• Single celled• Eukaryotic• Ingest or produce

food• Some animallike

What is an Animal?• Are members of Kingdom Animalia• Are multicellular• Are Eukaryotic • Are Heterotrophs• Lack cell walls

• Usually have a method of

movement

• Most reproduce sexually

• Require oxygen

What is an Animal?• Multicellular: Having more than one cell • Eukaryotic: Organisms whose cell contain a nucleus

• Heterotroph: Organisms that obtain energy from the foods it consumes; also called a consumer.

Important Latin roots• Cyte = cell • Zoa or zoo = animal• Demo = people• Epi = on or on top• Coel = cavity • Oid = like• Ation = to form

• Taxon = unit• Nomen = name• Clature = system• Pori = pore• Fera = to have or

bear• Cephala = head• Homologous = similar

in origin

2 Types of Animals• Invertebrates: Animals that do not have a backbone or a vertebral column

• Vertebrates: Animals that have a vertebral column, or backbone

What Animals Do to Survive

• Animals carry out the following essential functions:

1. Feed2. Respire3. Circulation4. Excrete5. Respond6. Move7. Reproduce

Essential Functions1. Feeding: Animals feed in a large variety of ways.

– Carnivore: Eats meat ONLY

– Herbivore: Eats plants ONLY

– Omnivore: Eats meat & plants

– Detritivore: Feeds on plant and animal remains and other dead matter called detritus (Includes poop).

Essential Functions: Feeding Continued

• Some animals form symbiotic relationships.

Symbiosis: Is the relationship in which two species live closely together

a. Mutualismb. Commensalismc. Parasitism

Essential Functions: Feeding Continued

a. Mutualism: Symbiotic relationship in which both species benefit from the relationship.

Essential Functions: Feeding Continued

b. Commensalism: Symbiotic relationship in which one member of the association benefits and the other is neither helped nor harmed.

Barnacles on a Whale

Essential Functions: Feeding Continued

c. Parasitism: Symbiotic relationship in which one organism lives in or on another organism and harms it.

Essential Functions2. Respiration: Whether they live in water or

on land, all animals respire, which means they take in oxygen and give off carbon dioxide.

– Some can rely on diffusion of these substances through their skin

– Most have evolved complex tissues and organ systems for respiration

Essential Functions3. Circulation: Many aquatic animals

(ex: aquatic worms) rely solely on diffusion to transport oxygen & waste.

• Larger animals have some kind of circulatory system to move materials around within their bodies.

Essential Functions4. Excretion: A primary waste product of

cellular metabolism is ammonia, a poisonous substance that contains nitrogen.

– A buildup of ammonia & other wastes would kill an animal

– Animals have excretory system that either eliminates ammonia quickly or converts it into a less toxic substance that is removed from the body.

Essential Functions5. Response: Animals respond to events

in their environment using specialized cells called nerve cells.

– Nerve cells hook up together to form a nervous system

– Some nerve cells are receptors that respond to sound, light, and other stimuli

– The arrangement of nerve cells in the body changes dramatically from phylum to phylum

Essential Functions6. Movement: Some live their entire

lives attached to a single spot.– Most are motile, meaning that they move

Essential Functions

7. Reproduction: Most reproduce sexually by producing gametes.

– Maintains genetic diversity in populations

– Helps species evolve when the environment changes

– Many reproduce asexually & allows to increase numbers rapidly (inverts.)

Describe the Body Plans of Animals1. Symmetry: balance in body proportions

3 Types

Asymmetrical-Irregular shape Radial symmetry: can be

divided along any plane to produce 2 halves which look alike

Bilateral: can be divided only one way to produce mirror image halves

Symmetry Asymmetrical: Has no definite shape.

Symmetry

Radial Symmetry: Body is arranged in a circle like the spokes of a wheel.

Symmetry

Bilateral Symmetry: If divided lengthwise in half, both sides will match.

Bilateral Symmetry • Includes worms, insects & vertebrates

• Have external body parts that repeat on either side of the body

What type of symmetry?

Bilateral Symmetry

• Anterior End = Front End

• Posterior End = Back End

• Dorsal Side = Upper Side

• Ventral Side = Lower Side

2. Body arrangements:a. anterior: head region(front on upright man)

b. posterior: tail region (back on upright man)

c. dorsal: back or topd. ventral: abdomen(belly) or bottom

Anatomical Terms (cont)• Medial - close to the middle• Lateral

– Close to the side or movement away from middle

• Distal– Away from the main part

• Proximal– Close to the main part

Anatomical Terms (cont)

• Oral– End with the mouth

• Aboral– Opposite end of the mouth

• Cephalic– Toward head

• Caudal– Toward tail

3. Body Development• As an embryo develops, three germ

layers form:

a. Ectoderm•  becomes nervous system, epidermis of the skin,

pituitary, lens of eye

b. Mesoderm•  becomes muscles, skeleton, notochord, circulatory

system, kidney, reproductive system

c. Endoderm

•  becomes lining of digestive tract, liver, pancreas, epithelial lining of lungs, many endocrine glands

a. Acoelomates- no body cavity lined with mesoderm

• EX: sponges, cnidarians, & flatworms

4. Body Cavities

b. Pseudocoelomates- partial body cavity lined with mesoderm

• “Tube within a tube” body plan

• EX: roundworms

c. Coelomates- true body cavity lined with mesoderm

• EX: all other animals

Advantages of a body cavity (coelom or pseudocoelom):

• Fluid in cavity helps distribute food, wastes, hormones, etc. from one end of animal to the other

• Better distribution allows animal to grow larger • A place to put things, like new organs

5. Cephalization-concentration of sense organs- developed nervous system

THE ANIMAL KINGDOM OVERVIEW

• Invertebrates-no backbone• Vertebrates or Chordates-backbone

Section 29-1

RadialSymmetry

Deuterostome Development

Coelom

Pseudocoelom

Protostome Development

RadialSymmetry

Three Germ Layers;Bilateral Symmetry

TissuesMulticellularity

Chordates Echinoderms Arthropods

Annelids Mollusks

Roundworms

Flatworms

Cnidarians

Sponges

Single-celled ancestor

Invertebrate Cladogram

Protostomes vs. Deuterostomes• Zygote cleaves to become blastula and then

forms gastrula. The blastopore of the gastrula can become either the mouth or the anus of the organism

• Protostome- Blastopore becomes the mouth. Ex-Annelids, Mollusks and arthropods

• Deuterostome- Blastopore becomes anus. Ex-Chordates

The End