Zoology An Introduction Zoology Study of animals In

Zoology An Introduction

Zoology • Study of animals • In this class- Important Kingdoms. Protista- some animallike organisms considered to be evol. precursors to animals ANIMALIA- are ANIMALS • Latin “zoa” or “zo”- means animal

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 obtains energy from the foods it consumes; also called a consumer.

Important Latin roots • • Cyte= cell taxon=unit Zoa or zoo= animal omy= lar/rules Demo= people nomen=name Epi=on or on top clature=system Coel=cavity pori=pore Oid=like fera= to have or bear Ation= to form 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 has a vertebral column, or backbone

What Animals Do to Survive • Animals carry out the following essential functions: 1. Feed 2. Respire 3. Circulation 4. Excrete 5. Respond 6. Move 7. Reproduce

Essential Functions 1. 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. Mutualism b. Commensalism c. 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 Functions 2. 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 Functions 3. Circulation: transport of nutrients and wastes • 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 Functions 4. Excretion: releasing wastes – 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(uric acid) that is removed from the body.

Essential Functions 5. 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 Functions 6. Movement: • Some animals live their entire lives attached to a single spot (sessile) • 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. )

Body Plans of Animals Symmetry: balance in body proportions 3 Types Asymmetrical. Irregular shape Bilateral: can be divided only one way to produce mirror image halves Radial symmetry: can be divided along any plane to produce 2 halves which look alike

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

Body arrangements: a. anterior: head region(front on upright man) b. posterior: tail region (back on upright man) c. dorsal: back or top d. 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

Cephalization-concentration of sense organs- developed nervous system- “formation of head"

Embryonic Development • As 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

Body Cavities a. Acoelomates- no body cavity lined with mesoderm • EX: sponges, cnidarians, & flatworms

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

THE ANIMAL KINGDOM OVERVIEW • Invertebrates-no backbone • Vertebrates or Chordates-backbone

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- “first mouth” Blastopore becomes the mouth. Ex-Annelids, Mollusks and arthropods • Deuterostome- “second mouth” Blastopore becomes anus. Ex-echinoderms, hemichordates, chordates

Embryonic Development STEP 1 STEP 2 40

Embryonic Development • Protostome – Blastopore becomes mouth • Deuterostome – Blastopore becomes anus 41

Checkpoint 1. What are the main characteristics all animals share? 2. Evidence suggests that animals evolved from ______. 3. What are three animal body types? 4. What are three germ layers? 5. What is the difference between a protostome and a deuterostome?

The End