Chapter 8: Deuterostomes Gen Bio 1 LAB

What does the blastophore develop into in the deuterostomes?

Anus

What kind of symmetry do deuterostomes have?

Bilateral

What are types of deuterostomes?

Enchinoders, chordates, hemichordates,

What kind of symmetry do hemichordates have as adults?

Pentaradial

What are the types of echinoderms?

Sea stars, sea cucumber, sand dollar, sea urchin

Madreporite

Aboral side, sieve like

Echinoderm water vascular system

Water enters through a madreporite an aboral side, into central ring canal then into radial canal in each arm

What do lateral canals contain?

Bulb like ampulla and protruding tube feet

What are tube feet used for en enchinoderms?

Gas exchange, feeding, locomotion

What are the types of chordates?

Lancelets, tunicates, vertebrates

4 common features of chordates

Pharyngeal slits, dorsal nerve cord, notochord, post anal tail

Pharyngeal slits

Series of openings in the throat region that connect the inside to the outside

Dorsal nerve cord

Runs along dorsal side of organism, may expand into brain + head region

Notochord

Cartilaginous rod right underneath nerve cord

Post anal tail

Tail beyond anus

What do lancelets not contain?

Fins, jaws, heart, or brain

What do lancelets have throughout their lives?

Notochord, dorsal nerve cord extending to head region, pharyngeal slits, post anal tail

When do tunicates exhibit all chordate features?

Larval stage only

What happens after larval stage in tunicates?

Attach to substratum and lose tail and notochord, transform adults

What other special features do vertebrates have?

• Anterior portion of nerve cord expands and develops into brain protected by skull

• Rest of nerve cord becomes spinal cord

• Dorsal vertebral colum (backbone) acts a flexible support for body + protects spinal cord

What are types of vertebrates?

Lampreys, sharks, bony fish, amphibians, reptiles, birds, and mammals

What kind of lifestyle do lampreys have?

Parasitic- jawless mouth w/many rows of teeth

What is the primary support of a lamprey body?

Prominent notochord

Why are shark’s evolved jaws important?

Enhanced capability to feed

Why do sharks constantly swim?

To stay afloat

What do bony fish have for support?

Bony skeleton

Why do bony fish have swim bladders?

Buoyancy

Why do bony fish have scales?

Protection and movement enhancement

Operculum

Help bring oxygen rich water to gills

Where do amphibians start their life?

In water, eggs are laid in water

What kind of fertilization do amphibians have?

External

Amphibian adaptations to terrestrial life style

Hop with legs, breathe through skin and lungs

Which were the first animals to become fully terrestrial

Reptiles

How is fertilization in reptiles?

Internal

What is the significance of scaly skin in reptiles?

Reduce water loss

What kind of eggs do reptiles lay?

Amniote eggs

Amniote eggs

Tough outer shell, nutritional supply, extraembryonic membrane

Why is it important tat amniotic membrane and fluid surround embryo?

So that embryo development takes place in watery environment even though egg is laid on land

What are the front legs in birds?

Wings

What are developed feathers important for in birds?

Flight, thermoregulaiton, courtship displays

Barbs

Branches of filaments

What are structures common in mammals?

Mammary glands, sweat glands, hair

Endothermy

Care for young

What are the types of mammals?

Monotremes, marsupials, placental mammals

Monotremes

Lay amniote eggs

Marsupials

Allow fetuses to finish their development in their mother’s external pouch

Placental Mammals

Have a placenta to allow the exchange of nutrients and wastes between fetus and mother

What is the closet living relatives in humans?

Chimpanzee

Mastoid process

Conical projection of temporal bone where jaw muscles attach to the skull

Foramen magnum

A large hole on the underside of skull where spinal cord exits cranial cavity

Foramen magnum in upright vertebrates

A FM positioned more forward than animals that don’t

Foramen magnum in humans

More centered so human body stands straight for bipedalism

Chimpanzee FM

More toward back of skull so spinal cord exits cranial cavity at an angle

Which of the following statements about echinoderms is true?

Larvae are bilaterally symmetrical but become radially symmetrical

Which structure is shared by lancelets, tunicates, and vertebrates at certain stage of their life?

Notochord

What characteristics allows reptiles to be fully terrestrial animals?

Amniote eggs with a tough outer shell

What does external reproduction in amphibians involve?

External fertilization

Which vertebrate does not have bones to support its body shape?

Sharks

What covers the bony fish gills?

Operculum

What serves as a conical projection from the temporal bone in human skull, providing attachment for jaw muscles?

Mastoid process

Which of the following is true about birds and crocodiles?

They both lay amniote eggs