Download Notes: Animals: The Vertebrates

Animal Notes
The Chordates: Non-Vertebrates and Vertebrates
(Parts of Chapters 30 – 33)
I. Chordates
A. Characteristics of Chordates:
a. hollow nerve cord (dorsal – back)
b. notochord – long supporting rod that runs through the body
below the nerve cord; becomes the backbone in some animals
c. pharyngeal pouches – structure near mouth; some form gills
d. a tail
II. Nonvertebrate Chordates
A. Tunicates
a. Soft –bodied; live in ocean
b. filter feeders
c. “sea squirts”
B. Lancelets
a. small, fishlike
b. live in ocean sand
c. gill slits for breathing
III. Vetrtebrate Chordates
A. Fish (*fish are most diverse chordate group)
a. Groups of fishes
1. Jawless Fish – no true teeth or jaws
2. Sharks – skeleton made of cartilage, not bone (ex: sharks,
rays, skates)
3. Bony Fishes – skeleton made of calcified bone
b. General Characteristics of all Fish
1. live in water (aquatic)
2. have paired fins
3. have scales (most)
4. all modes of feeding
5. Digestion pathway: mouth -> esophagus -> stomach ->
pyloric ceca -> anus
6. Liver and pancreas – secrete enzymes into digestive
system that help break down food
7. Respiration – gills
III. Vertebrate Chordates (fish continued)
8. Circulation – closed; heart pumps blood in a single loop
i. Flow of blood: (heart -> gills -> rest of body ->heart)
ii. The heart contains an:
atrium – collects blood
ventricle – pumps blood to body
9. Excretion – kidneys remove wastes and control amount of
water in the body
10. Movement – paired sets of muscles
i. swim bladder – gas filled organ that controls
position in water (buoyancy)
11. Response – well developed
i. Brain contains:
cerebrum – voluntary activities
cerebellum – coordinates body movements
medulla oblongata – controls internal organs
12. Reproduction – eggs fertilized externally or internally
B. Amphibians (“double life” – live in water and land)
a. Groups of amphibians
1. frogs
2. salamander
b. General Characteristics of Amphibians
1. live in water when young (tadpole)
2. live on land as adult
3. moist skin with mucous glands
4. no scales or claws
5. Respiration :
i. young - gills; breathe through skin
ii. adults - have lungs; some through skin
6. Circulation –
i. closed
ii. double loop
iii. 3 chambers (left and right atrium and a ventricle)
7. Excretion –
i. kidneys
ii. ureters
iii. urinary bladder
iv. cloaca
v. outside
8. Reproduction
i. external fertilization
ii. eggs without shells and dry out if not in water
9. Response – well developed, similar to fish
i. Nictitating membrane – membrane that covers eyes
ii. Tympanic membrane – eardrums (respond to
sound)
10. Niche – live near water; warm, moist places; some
poisonous; declining population)
C. Reptiles
a. Groups of reptiles
1. Lizards
2. Snakes
3. Crocodiles
4. Turtles and Tortoises
b. General Characteristics of Reptiles
1. Dry, rough and scaly skin
2. Lungs
3. Terrestrial (land) eggs with several membranes (Amniotic
egg)
4. Dinosaurs were reptiles
5. Temperature control
i. Ectotherms – depend on outside and behaviors to
control body temperature
6. Carnivores
7. Respiration – 2 spongy lungs with muscles around rib cage
8. Circulation – double loop; 4 chambers (2 atria and 2
ventricles)
9. Excretion – produce urine; conserve water by absorbing
before urination
10. Response – well developed
11. Movement – well developed strong muscles to run or walk
12. Reproduction – internal fertilization; eggs develop outside
female body
13. Niche – many habitats are being destroyed
D. Birds
a. Groups of birds (many species!)
1. Birds of prey – hawks and eagles
2. Parrots
3. Ostriches
4. Perching birds – songbirds (most common >5,000 species)
5. Pelicans
b. General Characteristics of birds
1. Reptile - like
2. Endothermic – control body temperature internally
3. Outer covering of feathers
4. Front limbs are wings
5. Legs with scales
6. Strong lightweight bones with air spaces
D. Birds (continued)
7. Digestion pathway (mouth-> crop-> gizzard ->stomach ->
small intestine -> cloaca)
8. Respiration – air sacs and lungs
9. Circulation – 4-chambered hearts; 2 separate loops
(oxygenated and deoxygenated)
10. Excretion – similar to reptiles
11. Response – well developed; complex sense organs (ex: eyes)
12. Movement – fly, walk, and or run
13. Reproduction
i. internal fertilization with cloaca
ii. amniotic eggs with hard outer shell
14. niche - migration
E. Mammals
a. Groups of mammals
1. Monotremes (platypus) and Marsupials (kangaroo)
2. Placental mammals (some examples: rodents, sea lions,
armadillos, bats, elephant, monkeys, whales, humans)
i. young develop inside placental mammals; nutrients
wastes and gases exchange through mother’s placenta
b. General Characteristics of mammals
1. Mammary glands – produce milk for young
2. have hair
3. breathe air
4. 4-chambered hearts
5. endotherms
6. have fat layer below skin to help control body
temperature
7. jaws and teeth
8. respiration – diaphragm (muscle below lungs)
9. Circulation – 4-chambered heart (2 separate loops)
10. Excretion – kidneys
11. Response – most highly developed brains; large
i. cerebral cortex – thinking and complex behaviors
i. highly developed senses
12. Endocrine glands – secrete hormones that control body
processes
13. Immune system – helps fight disease
14. Reproduction
i. internal fertilization
ii. care for young