AP Bio Ch 34

Monotremes reproduction

egg-laying

Amnion

the amnion protects the embryo in a fluid filled cavity that cushions against mechanical shock

How do adult frogs breathe? (two ways)

-Gas exchange over skin -Bring in air through nostrils

Make a list of at least five traits of mammals, including the two in the concept heading. Put an asterisk (*) next to the traits unique to mammals

-hair -produce milk -subcutaneous fat -kidney -endothermic

Read the second paragraph about reptiles carefully, and then make a list of five characteristics of reptiles.

1) scales that contain the protein keratin 2) lay shelled eggs on land 3) internal fertilization 4) ectothermic 5) leathery skin

What are four avian adaptations for flight?

1) wings and feathers 2) lack urinary bladder 3) porous bones 4) gonads shrink during non-mating season

One of the important characteristics is a notochord. What is a notochord?

a longitudinal, flexible rod located between the digestive tube and the nerve cord. provides skeletal support to chordates

What is an amniotic egg? How has it enabled animals to occupy a wider range of terrestrial habitats than amphibians can?

an egg that has specialized membranes that function in protection, nourishment, and gas exchange. it allowed the embryos to occupy land in a fluid filled sac which eliminated the need for water

Important features of alligators and crocodiles

aquatic habitats, upturned nostrils

Vertebrates are not the only chordates. The lancet displays a number of chordate characteristics, and the ancestral chordate may have resembled a lancet. Describe a lancet.

blade-like shpae; larvae have notochord, dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail. adults can reach 6 cm and retain many key chordate features

What does the class name Amphibia mean?

both ways of life

The "fishes" with a bone skeleton are aquatic Osteichthyes. How do they breathe?

by drawing water over their gills

What does the name Chondrichthyes mean? What material makes up their skeleton?

cartilage fish; cartilage

We are vertebrates. What phylum do we belong to?

chordata

Yolk sac

contains yolk and stockpile of nutrition

Dorsal hollow nerve cord

develops from ectoderm and develops into spinal cord and brain

Marsupials reproduction

develops in marsupium

Eutherians reproduction

develops in uterus

Allantois

disposal sac for certain metabolic wastes produced by the embryo

What other phylum might be considered our close relatives? Why?

echinodermata; both are deuterostome development

Chordates are the first group to show a dorsal nerve cord. Which embryonic layer forms the nerve cord?

ectoderm

Fertilization in amphibians is ______________________. The eggs lack a shell, and mortality is very high.

external

As a human, you are in the class Mammalia and the order Primates. What features are unique to primates only?

flat nails, large brain, flat face, opposable thumbs

Important features of birds

flight, feathers

What does tetrapod mean?

four feet

Important features of lizards

four limbs, external ears, moveable eyelids

For us, as vertebrates, what remains of the notochord?

gelatinous disks sandwiched between vertebrae

Pharyngeal gill slits develop into what structures in the fishes? What is their function

gills; gas exchange

Eutherians example

humans

What is the oldest lineage of vertebrates? ___________________ They are jawless parasitic fish with a skeleton made of ___________________________. Look at the mouth! Lampreys have invaded the Great Lakes and damaged the fishing industry there.

lampreys; cartilage

Notochord

longitudinal, flexible rod between the digestive tube and nerve cord

Fishes, amphibians, and reptiles are ectothermic. What does this mean?

means they use external sources such as the sun to regulate body temperature

What factors tie amphibians to a life near water?

need to keep skin moist and lay eggs in water

Important features of turtles

no holes in skull behind eye socket, box-like shell, terrestrial and marine habitats

Important features of snakes

no legs or arms, loosely articulated jaws and chemical sensors. lack eardrums

Pharyngeal slits

one of the slits that form from pharyngeal clefts and open into the pharynx, later developing into gill slits in many vertebrates

Marsupials example

opossum, kangaroo, koala

In tetrapods, what do the gill slits become?

parts of ear and other structures in head and neck

Monotremes example

platypus and echidna

What groups have an amniote egg?

reptiles and mammals

What animals are in the class Amphibia?

salamanders, frogs, caecilians

What is the body covering of a reptile? How does this enable it to live a more terrestrial life?

scales; scales prevent animals skin from dessication and abrasion

What animals are in the clade Chondrichthyes?

sharks, rays, and their relatives

Gnatho- means "jaw," and -stome means "mouth." This group includes the sharks, fishes, amphibians, and reptiles. From what structure is it believed that jaws evolved?

skeletal rods that supported anterior pharyngeal gill slits

Why do sharks have to swim continuously?

so they don't sink, and ensuring that water flows in through the mouth and out through gills ensuring gas exchange

Post anal tail

tail that extends posterior to the anus

Chorion

the chorion and the membrane of the allantois exchange gases between the embryo and the air

What is internal fertilization? How does this enable reptiles to reproduce on land?

the unions of sperm and egg inside the female body. enables reptiles to reproduce on land because typically species who have external fertilization need to release their sperm into water in order to reach the female

Birds are in the reptile clade. Which extinct group included their closest relatives?

theropods

What is the function of a swim bladder?

to maintain buoyancy equal to the surrounding water

What animals are in the reptile clade?

tuataras, lizards, snakes, turtles, crocodilians, and birds

Frogs have a life cycle with an aquatic larval stage, the tadpole. How do tadpoles breathe?

using gills