Bellwork 1: 1-8-2014
Briefly write about a real
scientific observation you
made over the break.
I will only call on 3 of you to
share
Vertebrates
Chapter 3
Vertebrates
There are more than 50,000
species of vertebrates in this
world.
A vertebrate is an animal with
a backbone that supports and
protects the spinal cord.
Vertebrates All Have
All vertebrates have:
Backbones, brains, craniums
(skulls), closed circulatory systems
with veins, arteries, and
capillaries, continuously beating
heart to keep blood flowing
Vertebrates 2 Groups
Vertebrates can be divided into two groups:
Ectotherms & Endotherms
Ectotherms are animals that use the
environment to regulate their body
temperatures.
They generally bask in the sun or bury
themselves for heat or cooling
Reptiles, fish, and amphibians are all
ectotherms
Ectotherms
Endotherm
Endotherms are organisms that
internally regulate their body
temperatures.
Their internal temperature remains
generally the same whether they are in
hot or cold environments
Birds and mammals are examples of
endotherms.
Endotherms
Vertebrates
Vertebrates’ tissues are made mostly of
salty water
This tissue freezes/dies at 31.1’ F
Most vertebrates live in areas with
temperature ranges from 32’-122’F
Some have adapted to harsher
environments
Adaptations
Polar bears have thick
layers of fat to insulate
them from the cold
Some fish have
chemicals in their blood
that act like antifreeze
to allow them to live in
cold arctic water
Review
1. What do vertebrates have in common?
Backbones, brains, craniums (skulls),
closed circulatory systems with veins,
arteries, and capillaries, continuously
beating heart to keep blood flowing
2. What are the two general groups of
vertebrates?
Ectotherms, endotherms
Review
3. What distinguishes these two groups?
Their ability, or lack there of, to regulate
their internal temperature
4. In general, what animals are part of each
group?
Ectotherms: reptiles, fish, amphibians
Endotherms: birds, mammals
Ectotherms
Ectotherms’ body temperature and body
functions are regulated by the outside
temperature
Not cold-blooded: ectotherms are not
called cold-blooded anymore because
some actually have a higher internal
temperature than endotherms
Air vs. Water temp
Because air temperatures change
more than water temperatures, land
ectotherms vary more than water
ectotherms
Due to this variance, land
ectotherms seek sun or shade to
help regulate these changes
Ectotherms Regulation
Many ectotherms hide from
predators at night because they
are sluggish from lack of heat
energy
Others prey at night (mostly in
hot climates) and stay out of
extreme temperatures during the
day
Ectotherm Regulation
Ectotherms can also change
color to help regulate their
body temperatures.
Darker colors absorb heat
while lighter colors reflect
heat.
Review
1.What is the distinguishing feature
of ectohterms?
They regulate their internal
temperature using the sun’s energy
2. Why is cold-blooded a confusing
term to describe ectotherms?
Many ectotherms have warmer
internal temperatures that
endotherms.
Review
3. Which organisms have an
easier time regulating their body
temperatures, ectotherms that
live on land or water? Why?
Those that live in water
Because water temperature is
not as volatile as air
temperature.
Review
4. What are some ways that
ectotherms regulate their
body temperatures?
Basking, burying, changing
color
Reptiles
Over 7000 species of reptiles
The study of reptiles and
amphibians is herpetology
Herpo in Greek is “to creep or
crawl”
All reptiles have lungs and
scaly skin
Reptiles
Most reptiles shed their
entire skin at once rather
than one cell at a time like
us!
Reptiles
Scales protect the skin
underneath from drying out
Retiles have bone skeletons and
most have teeth
Their teeth range from blunt
crushing teeth to thin needle-like
fangs
Reptiles
Many reptiles have a
muscular, flexible, sticky
tongue for catching
insects.
Reptiles
Reptiles generally have well
developed organs. (snakes are deaf
and some lizards don’t have eyes)
Crocodiles and alligators have
very advanced organ systems that
have allowed them to thrive for
millions of years.
Reptiles
All reptiles reproduce through
internal fertilization
Some lay leathery eggs and the
young are hatched
Others store their eggs inside their
bodies and the young are born live
Live birth
Reptiles
Young reptiles look like
miniature adults
Most reptile mothers do not
take care of their young
Common Reptile Groups
1. Turtles
2. Lizards
3. Snakes
4. Alligators and Crocodiles
Turtles
Turtles’ bodies are protected
by a shell formed of plates of
bone
Some shells can support a
weight 200 X their own!
Turtles
Turtles
Turtles are toothless, but have a
beaklike structure to eat plants
and animals
Bellwork
Make a hypothesis about why you
think crocodiles have survived for so
long.
Get out a sheet of paper to take
notes during the film.
Crocodiles
http://www.youtube.com/watch?v=dsHHSCafGrk
During the film, write down
at least three functions of the
crocodile that have helped it
to survive for so long. I will
call on you randomly to share
what you have written;-)
Fish
Most have smooth, streamlines, scale covered
bodies
Most have fins
All have gill slits for breathing underwater
Water passes through the gills, oxygen is
absorbed by the blood vessels there, and
carbon dioxide is released back into the water
Fish
Most fish have a well developed
nervous system to sense their
environment
Most can see in color, can smell and
taste
Fish
Sharks can detect small amounts
of blood in huge amounts of
water to help find wounded
animals
Most fish don’t hear well, but
can sense vibrations in the water
Fish
Most fish are either male or female
Some, however are born as one sex and
develop into the opposite sex
Fish
Most fish reproduce through external
fertilization:
The female releases jelly coated eggs into the
water and the male fertilizes them with
sperm
A few species of fish reproduce through
internal fertilization and have live birth
Fish
As a group, fish eat almost everything in the
water
They use very different hunting techniques
Swordfish slash through a group of fish and
return to eat the carcasses
Angler fish dangle wormlike lures to tempt their
prey
The archer fish can spit out of water to catch
insects!
Many others hide and launch sneak attacks
Fish
Fish species can be divided into the
following groups:
Jawless Fish
Sharks
Skates
Rays
Bony Fish
Jawless fish
About 60 species of jawless fish
They have round mouths like suction
cups
Their skeletons are made of cartilage
They don’t have scales
Lampreys and hagfish are two examples
Jawless Fish
Hagfish live on the ocean floor and eat
dead/decaying carcasses
Lampreys have about 125 teeth they use
to drill holes into the scales of fish,
attach themselves to the fish, and suck
their blood and bodily fluids
Sharks Skates and Rays
The fish in these groups all have
skeletons made of cartilage
They all have small pointed
structures called dentilces, which
make the skin coarse, like
sandpaper
Rays and Skates
Rays and Skates have flat bodies
with a wing like pectoral fin and
a long, spike like tail
The largest ray is the manta ray
Sharks
There are about 350 species of
sharks
Most actively hunt large prey
Whale shark is the largest shark,
and fish in the world
Shark Finning
http://www.youtube.com/watch?v=mO7hvOtYnck
What problem is facing sharks today?
How is this affecting our oceans?
Bony fish
Over 23750 known species
From 1 cm (the goby) to 11 feet (sun fish)
Most have 2 eyes without lids,
Two nostrils for smelling, not breathing
Tongues for touching, not tasting
Swim bladders (balloon-like organs they can
fill or empty of gases to allow them to rise or
sink in the water
Salmon
http://www.youtube.com/watch?v=5DqjsWsY8-g
Describe the life cycle of the salmon.