bellwork 1: 1-8-2014 briefly write about a real scientific observation you made over the break. i...
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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
VertebratesChapter 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 GroupsVertebrates can be divided into two groups:
Ectotherms & EndothermsEctotherms are animals that use the environment to regulate their body temperatures.They generally bask in the sun or bury themselves for heat or coolingReptiles, fish, and amphibians are all ectotherms
Ectotherms
EndothermEndotherms 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
VertebratesVertebrates’ 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
Review3. 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, amphibiansEndotherms: birds, mammals
EctothermsEctotherms’ 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 RegulationMany 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.
Review1.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 waterBecause 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
ReptilesOver 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.
ReptilesReptiles 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
TurtlesTurtles 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.
Crocodileshttp://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
FishMost fish are either male or female
Some, however are born as one sex and develop into the opposite sex
FishMost 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
FishAs 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
FishFish species can be divided into the following groups:
Jawless Fish
Sharks
Skates
Rays
Bony Fish
Jawless fishAbout 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 fishOver 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.