Transcript Chapter 31 Reptiles and Birds

Chapter 31
Reptiles and Birds
Mammals
Birds
Amphibians
Fishes
Nonvertebrate
chordates
Invertebrate ancestor
Reptiles
Reptiles
https://www.youtube.com/watch?v=K-I34T3fGdY VIDEO
What is a reptile?
• Vertebrate
• Dry, scaly skin where scales can be
smooth or rough and most times shed
• Lungs
• Terrestrial eggs with several membranes
Body Temperature Control
• Ectotherms – rely on behavior to control
body temperature
• If they want to get warm they go into the
sun and if they want to cool off they get
out of the sun
Feeding
• Herbivores – iguanas
• Carnivores – snakes, crocs, and alligators
Respiration
• Most species have 2 lungs, except snakes
that have one lung
• Lungs are more spongy than amphibians
to better exchange gases – reptiles can
NOT exchange gases through skin
Circulation
• Closed, double loop heart system
• 2 atrium and 1 or 2 ventricles
• Most reptiles don’t have a completed
septum
• Crocs and gators have most developed
hearts (much like a mammal heart)
The Structure of a Turtle’s Heart
Section 31-1
Liver
Kidney
Heart
Cloaca
Bladder
Lung
Digestive
tract
To
body
To
lungs
Right
atrium
From
lungs
Left
atrium
From
body
Ventricle
Incomplete
division
Excretion
• Urine either contains ammonia or uric acid
• If mostly a water animal - ammonia (which
is toxic) is excreted because it can be
diluted
• If mostly a land animal – uric acid is
excreted (a white paste because water is
absorbed in cloaca)
Response
• Active during the day and have complex
eyes and see color very well
• Many snakes have a very good sense of
smell and some can detect heat and
ground vibrations
• Nostrils and sensory organs on roof of
mouth that can detect chemicals
• Simple ears with external eardrums
Movement
• Legs are larger and stronger than an
amphibian
• They can run, walk, swim, climb, dig
Groups of Reptiles
• 1) Lizards and snakes
• 2) Crocodilians – crocs, gators, caimans,
and gavials
• 3) Turtles and Tortoises
• 4) Tuataras
http://video.nationalgeographic.com/video/
kids/animals-pets-kids/reptiles-kids/turtleloggerhead-kids/
Reptile Review
• 1) What are characteristics of reptiles?
• 2) How are reptiles adapted to live on
land?
• 3) What are the four living orders of
reptiles?
Birds
Mammals
Birds
Amphibians
Fishes
Nonvertebrate
chordates
Invertebrate ancestor
Reptiles
• Silent Spring
• Rachel Carson wrote the book Silent Spring in the
1960s. As the title suggests, she describes waking up
on a spring morning, hearing none of the usual
chirping of songbirds and wondering what happened
to them. Carson’s book increased awareness of the
use of pesticides in the environment. Unfortunately,
one of the chemicals that had been used interfered
with the formation of the shells of birds’ eggs.
• With a partner, discuss and answer the
questions that follow.
• 1. What effect would weak eggshells have on
the population of birds? How might this cause a
“silent spring”?
• 2. If you were a legislator, what would you do
about the use of chemicals such as pesticides in
our environment?
What is a bird?
•
•
•
•
Reptilian-like animals
Maintain a constant internal body temp.
Outer covering of feathers
2 legs that are covered with scales and
used for walking or perching
• Front limbs modified into wings
• Feathers – mostly of protein, 2 types
(contour and down feathers)
Form, Function, and Flight
• 1) Body Temperature Control
– Endotherms – can generate their own heat
– High metabolism – which produces heat
– Feathers insulate body
2) Feeding
• Beak is adapted to type of food it eats
• Small birds lose heat faster so they must
eat more than larger birds
• Pathway of food: mouth, esophagus, crop,
stomach, gizzard, intestines, cloaca
Anatomy of a Pigeon
Brain
Esophagus
1 When a bird eats,
food moves down
the esophagus and
is stored in the crop.
Lung
Heart
Kidney
Crop
Air sac
2 Moistened food passes to the
stomach, a two-part chamber.
The first chamber secretes acid
and enzymes. The partially
digested food moves to the
second chamber, the gizzard.
Liver
First
chamber
of stomach
Gizzard Small
intestine
3 The muscular walls
of the gizzard squeeze
the contents, while
small stones grind the
food.
Pancreas
Large intestine
Cloaca
5 Undigested food is
excreted through the
cloaca.
4 As digestion continues,
the food moves through
the intestines.
3) Respiration
• Use of air sacs and breathing tubes in the
lungs insures that air flows into air sacs
and out of lungs in one direction
• Better because lungs are always exposed
to oxygen rich air
4) Circulation
• Closed, double loop system
• Heart has 4 chambers with a complete
septum dividing heart into left and right
halves
• Pathway: In right atrium, right ventricle,
lungs, left atrium, left ventricle, To body
Structure of a Bird’s Heart
Domestic pigeon
Right
atrium
Heart
Right
ventricle
Left
atrium
Left
ventricle
Complete
division
5) Excretion
• Very similar to reptiles – nitrogenous
waste is converted to uric acid, water is
absorbed by body and a white paste is
expelled from bird
6) Response
•
•
•
•
Brain is relatively large for animal’s size
Can see color very well
Can hear quite well
Taste and smell are NOT well developed
7) Movement
• Most birds fly – Which ones cannot??
• Skeleton is changed slightly to help a bird
fly – near collarbone, hollow bones
• Large chest muscles
Birds
have the following
adaptations to flight
Wings
Feathers
Strong chest
muscles
Efficient
respiratory
system
Efficient
circulatory
system
which are
that also
that power
that provide
that ensure
Homologous to
front limbs in other
vertebrates
Provide
warmth
Upward and
downward wing
strokes
One-way flow
of O2-rich air
O2 distribution
to body tissues
8) Reproduction
• Sex organs often shrink in size when not
breeding
• Bird eggs are amniotic with a harder shell
than reptile eggs
Groups of Birds
• 30 different orders
• Largest is the perching birds – songbirds
• Other groups:
–
–
–
–
–
–
–
Pelicans
Parrots
Birds of Prey – owls, eagles, hawks
Cavity nesting birds – woodpeckers
Herons
Ostriches
Penguins
https://www.youtube.com/watch?v=VjE0Kd
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https://www.youtube.com/watch?v=YTR21
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http://video.nationalgeographic.com/video/
worlds-deadliest-ngs/deadliest-eagles-vs
http://video.nationalgeographic.com/video/f
alcon_peregrine_velocity
Bird Review
• 1) Are birds ectotherms or endotherms?
• 2) What characteristics do birds have in
common?
• 3) How are birds adapted for flight?
• Bonus: Are robins in Iowa year round?