science 1 Flashcards
What are the chordate characteristics?
Notochord – flexible rod (pre-backbone / vertebral
column), nerve cord (pre-spinal cord) running down back
and slits in throat area.
Phylum Chordata: all vertebrates, few invertebrates
What are the vertebrate characteristics?
Endoskeleton
endo = inside
protects organs, body shape/support, muscle attachment
backbone (vertebral column, “spine”)
protects spinal cord and provides flexibility
what is are ectotherms?
an animal whose body temperature is
close to the temperature of their environment; its
body does not produce much internal heat ;
“cold-blooded”.
Example: fishes, amphibians, reptiles
what are endotherms?
an animal whose body temperature is
stable and often warmer than their environment; its
body regulates its own temperature by controlling
the internal heat it produces;“warm-blooded”
Example: birds, mammals
What are fish characteristics?
ectotherms (cold-blooded)
fins (movement)
scales
gills (respiration)
water lifestyle
mostly external fertilization
closed circulatory system
2-chamber heart (evolutionarily important)
oldest & largest vertebrate group
what are the fish classification?
Jawless Fish
Cartilagenous Fish
Bony Fish
Cartilage jaw, scales Bony
skeleton
skeleton
what are the jaw fish Characteristics?
No jaws
No scales
cartilage skeleton
Example: hagfish, lampreys
what are the cartilaginous fish Characteristics?
jaws
scales
cartilage skeleton
carnivores
Example: sharks, rays, skates
what are the bony fish Characteristics?
jaws
scales
bone skeleton
gill pocket with flap
swim bladder (internal gas-filled sac)
most fish (95%) are bony fish.
Example: trout, tuna, goldfish
what are the Amphibian Characteristics?
ectothermic: cold-blooded
juvenile life: water (gills),
movement: fins
1 loop circulatory system, 2 chamber heart, herbivores
adult life: land (lungs) but reproduce in water; thin, moist skin
movement: skeleton with muscle, leaping
2 loop circulatory system, 3 chamber heart, camouflage
carnivores
Example:
frog/toad, (loss of tail), external fertilization
salamander/newts (tail), internal fertilization
caecilians (no legs, no scales)
Time of
Transition Time
of Change
Why are amphibians at risk of extinction?
Population decline due to:
1] habitat destruction
2] pesticides / chemical pollutants –
harms delicate skin, tadpole mutations, kills
eggs
what are the characteristics of the reptiles?
ectothermic: cold-blooded
lung, scales (cover skin)
3 chamber heart (except alligators 4 chambers)
First true land lifestyle
adaptations to conserve water: skin (with scales
for protection, prevents evaporation) kidneys
(concentrated urine-liquid waste), amniotic egg
(leathery shell with internal membranes)
internal fertilization
Examples: snakes, lizards, turtles, alligators,
crocodiles, dinosaurs (extinct)
characteristics of lizards and snakes?
overlapping scales
shed scaly skin
environment: warm
Lizards: 4 legs with clawed toes, tail, ears,
eyelids, 2 lungs; most carnivores; walk/run
Snakes: no legs, streamline body, no ears,
no eyelids, 1 lung; carnivores; slither by
muscle contractions.
characteristics of Alligators & Crocodiles?
Largest living reptiles
Nocturnal carnivores
First living “care for young” behavior
Alligators: broad, rounded snout, few teeth
(mouth closed); max size: 15 ft, 1000 lbs
Crocodiles: tapered, pointed snout; pencil-like;
many teeth (mouth closed); max size: 17-20 ft,
2300 lbs
characteristics of turtles?
shell (with ribs & backbone) made of
fused scales
beak
herbivores & carnivores
characteristics of dinosaurs(extinct reptiles)?
earliest vertebrates with legs directly
beneath their bodies
Brachiosaurus walked on 4 legs
Tyrannosaurus rex ran on 2 legs
Ectotherms or First endotherms
First “care for young” behavior
Extinction: 65 myrs ago due to asteroid
impact in NE Mexico.
what are the bird characteristics?
endothermic: warm blooded (maintain constant body
temperature by food and feathers)
feathers
hollow bones
air sacs
First Major Group w/ 4 chamber heart
(prevents mixing of O2 rich and O2 poor blood)
eggs (hard shell)
“care for young” behavior (feed & protect until young able to fly)
internal fertilization
what are the birds adaptations for flight?
hollow bones
wings
large chest muscles
feathers (2 types):
contour feathers- steering & flight
down feathers- trap heat & warmth
air sacs- connected to lungs to obtain more oxygen
how do birds get food?
Bills – tear, strainer
Crop - internal storage tank
Two part stomach:
Part 1: chemical breakdown
Part 2: gizzard- physical breakdown
with
stones (gastroliths)
what are the characteristics of mammals?
Endotherms-warm blooded
4 chambered heart
fur/hair
Breast.mammary glands,milks
Care for young
Lung with dipgram
Advance nervous system (complex brain for problem solving)
Highly developed senses(large eyes,sonar,smell sensitivity
What are the mammals adaptation?
Teeth adaptation
Incisor
Canines
Molar
Cold environment adaptation
To keep warm food
fur/hair
Fat
Movement adaptation
walk,run,hop,swing,glide,swim(flippers)
What are the three groups of mammals?
monotones-lay eggs
marsupials-partly developer young live in a pouch
placental mammals-developed in side of mothers body,subdivided based on eating and movement
