vertebrates vertebrate survey anatomy and physiology of vertebrates

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Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

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Page 1: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Vertebrates

Vertebrate SurveyAnatomy and Physiology of

Vertebrates

Page 2: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Vertebrate Evolution Phylum Chordata is the group of

animals with a notochord – a flexible, supporting structure along the back

Contains the invertebrate chordates, and Subphylum Vertebrata, which have evolved vertebral columns

Serves as site for muscle attachment, protects nerve cord

Page 3: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Trends in Vertebrate Evolution Development of true bony jaws Development of paired pectoral and

pelvic limb girdles Development of bones Most vertebrates have two sets of

appendages (arms and legs), a closed circulatory system with a ventral heart, and either gills or lungs for breathing

Page 4: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Class Agnatha

Jawless fish Ex. Lampreys and hagfishes Only living vertebrates without jaws Parasites – survive by attaching

themselves to other fish or aquatic animals, feeding on their blood and body fluids

Scavengers – eat decaying carcasses

Page 5: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Class Chondrichthyes

Cartilaginous fish Ex. Sharks, skates, rays Skeletons made of cartilage Some are fearsome predators, other

eat small fish, mollusks, or plankton

Page 6: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Class Osteichthyes

Bony fish Contain half of all vertebrate species,

all aquatic habitats Ray-finned fish – sub-class containing

almost all fish species – well-developed bone systems, specialized jaws with teeth

Lobe-finned fish – sub-class with lungs and gills, relatives of amphibians

Page 7: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Class Amphibia (amphibians)

Lay eggs in water and spend part of their life cycle there (gills)

As adults, live on land and breathe through lungs

Most have moist skin, as part of their respiration occurs through skin

Page 8: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Class Amphibia

Examples include: Newts and salamanders (lay eggs in

water, hatch into young that resemble adults – larvae have gills that disappear and are replaced by lungs as they grow)

Frogs and toads (eggs hatch in water as tadpoles, which look completely different from adults)

Page 9: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Class Reptilia (reptiles) Fully terrestrial Reproduce by internal fertilization

– egg/sperm fuse within body of the female

Produce leathery eggs to prevent water loss

Dry scaly skin to retain moisture Developed lungs

Page 10: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Class Reptilia

Order Chelonia – turtles and tortoises, protective shell of bony plates (long fossil record)

Order Crocodilia – crocodiles, alligators, caimans (long fossil record)

Order Squamata – lizards and snakes, most abundant group

Page 11: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Class Aves (Birds)

Only vertebrates with feathers Used for flight and conservation of

body heat Lay eggs

Page 12: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Class Mammalia (mammals)

Named for presence of mammary glands, enable females to nourish young with milk

Have hair to retain body heat

Page 13: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Class Mammalia Three groups:

Monotremes – egg-laying mammals like duck-billed platypus – have body hair/fur, lay leathery eggs

Marsupials – live young born very early in their development and continue to develop within marsupium – kangaroos, koalas, opossums

Placental mammals – largest group, names for placenta (organ that connects mother with developing embryo, allows for nutrient, gas, and waste exchange)

Page 14: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Support and Movement All have an endoskeleton surrounded

by muscles and skin Vertebral column (backbone) is the

main part of the skeleton Adapting to life on land led to changes

in limb positions Amphibians had limbs that are

horizontal while reptile limbs are vertical to support increased body mass

Page 15: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Feeding and Digestion All food sources presented

problems as vertebrates evolved Meat is easy to digest, but must

first be caught then cut up for swallowing

Plant matter is easy to find, but must be pulverized and shredded before swallowing, and cellulose is hard to digest

Page 16: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Feeding and Digestion

Adaptations are present in teeth Meat requires teeth that hold, shred Plants require teeth that

grind/pulverize

Page 17: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Feeding and Digestion

Adaptations seen in digestive tracts Meat digests easily, so carnivores have

short digestive tracts that secrete enzymes to break down proteins

Plants need to be broken down slowly, so herbivores spend more time chewing/rechewing, and long digestive tracts full on bacteria help digest cellulose

Page 18: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Respiration (gas exchange)

Method/system depends on environment

Fish rely on gills for respiration Amphibians have gills as tadpoles

and poorly developed lungs as adults No muscles to inflate/deflate lungs Rely on diffusion through thin, moist skin

Page 19: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Respiration (gas exchange)

Reptiles are fully adapted to life on land and have more developed lungs that are divided into chambers to increase surface area

Reptiles also have muscles to inflate/deflate lungs

Page 20: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Respiration (gas exchange)

Mammals require higher rate of gas exchange because of higher metabolic rate

Most developed lungs Bronchi (air tubes) enter lungs

then branch to create more surface area, ending in alveoli

Page 21: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Respiration (gas exchange)

Alveoli are bubblelike structures surrounded in capillaries

Efficient at gas exchange, but inefficient because air must move in and out through the same passageway

Page 22: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Respiration (gas exchange)

Birds have highest requirements for lung efficiency because they fly

Have branched bronchi and alveoli like mammals, but also have air sacs within some bones

Air is pumped in one direction

Page 23: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Internal Transport

Closed circulatory systems Two types: single-loop and double

loop

Page 24: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Internal Transport

Single-loop circulatory systems are found in fish – blood is pumped from the heart to the gills where respiration takes place, then flows from the gills to the rest of the body, returning to the heart

Heart has two chambers – one atrium (receives) and one ventricle (pumps)

Page 25: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Internal Transport

Vertebrates with lungs have a double-loop circulatory system

First loop carries blood between the heart and lungs (pulmonary)

Second loop carries blood between the heart and the rest of the body (systemic)

Page 26: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Internal Transport

Amphibians and reptiles have a three-chambered heart – two atria and one ventricle

Birds and mammals have a four-chambered heart – two atria and two ventricles

Page 27: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Temperature Control

Vertebrates need to control their body temperature because chemical reactions operate differently at various temperatures

Need a way to heat the body, conserve that heat, and eliminate excess heat

Page 28: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Temperature Control

Fish, amphibians, and reptiles are ectothermic because they rely on interactions with their environment to control body temperature

Lay in sun to warm themselves, stay in shade or burrow to cool down

Page 29: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Temperature Control Mammals and birds are endothermic

because they generate heat in body tissues through chemical reactions in the body

Also have layers of fat and fur/feathers to conserve heat

Shivering generates more heat, panting or sweating dissipates heat

Page 30: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Excretion Elimination of nitrogen-containing

wastes linked to maintaining water balance

Aquatic vertebrates get rid of ammonia by diffusion (fish through gills, amphibians through skin)

They also have the beginnings of a kidney (primitive, gets more complex)

Page 31: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Excretion

Mammalian kidney most complex Use the conversion to urea and

uric acid and concentration to conserve water

Urea eliminated in urine, uric acid in solid waste

Page 32: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Response All vertebrates are cephalized Bundle of nerves and neural

connections in head called the brain, and the long, thick collection of nerves running down the back is the spinal cord

Spinal cord protected by vertebral column

Page 33: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Response Pairs of nerves run out between

individual vertebrae to connect muscles, organs, and sensory receptors around the body

More complex behavior means more complex brain

All vertebrates have a cerebrum (thinking) and cerebellum (balance, coordination, movement)

Page 34: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Reproduction

All vertebrates reproduce sexually Fish and amphibians have external

fertilization Female lays thousands of eggs in

water, male deposits sperm Young develop and hatch in water

Page 35: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Reproduction

Reptiles, birds, and mammals have internal fertilization (inside female) Fewer eggs are produced Developing embryo is nourished inside

the egg by a yolk (food) and wrapped in membranes (called the amniotic egg)

Membranes bathe embryo in liquid and receive and store wastes

Page 36: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Reproduction

Amniotic egg also has a shell for protection and allows for gas exchange

Important step in evolution – no water necessary

Page 37: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Reproduction

How eggs are handled is different amongst vertebrates

Oviparous animals lay their eggs, and the embryo completes its development and hatches outside of the female’s body

Page 38: Vertebrates Vertebrate Survey Anatomy and Physiology of Vertebrates

Reproduction

Ovoviviparous animals keep their eggs inside the body until the embryo fully develops and hatches

Viviparous animals have eggs with very little yolk (if at all) because the female nourishes the embryo internally for a long period of time, and the young are born alive (do not hatch)