Interest Grabber

1
Interest Grabber
Section 33-1

• Covering the Chordates
• Though all chordates share certain
  characteristics, they are extremely diverse. With
  a partner, identify the characteristic body
  covering for each of the six major groups of
  animals listed below. Then, explain how that
  covering is useful for that group of animals.
• 1. Nonvertebrate chordates
• 2. Fishes
• 3. Amphibians
• 4. Reptiles
• 5. Birds
• 6. Mammals

2
Section Outline
Section 33-1

• 331 Chordate Evolution
• A. Chordate Origins
• B. The Chordate Family Tree
• C. Evolutionary Trends in Vertebrates
• 1. Adaptive Radiations
• 2. Convergent Evolution
• D. Chordate Diversity

3
Phylum Chordata

• All chordates are distinguesed by the presence of
  four anatomic structures during embryonic
  development
• Notochord- flexible rod that runs longitudinally
  between the gut and nerve cord.
• A hollow, dorsal nerve cord
• Pharyngeal slits
• Postanal tail (tail that extends beyond the
  anus.)
• In many adult chordates, some of these structures
  have been modified, diminished, or eliminated

• Divided into three subphyla
• Cephalochordata tiny marine animals. Include
  lancelets.
• Urochordata include tunicates, which have a
  larval and adult stage.
• Vertebrata contain a backbone, which is a body
  covering enclosing the nerve cord. Most also
  have an appendicular skeleton and a closed
  circulatory system with a two to four chamber
  heart.

4
Figure 301 The Generalized Structure of a
Chordate
Section 30-1
5
Lancelets
Tunicates
Platypus
http//www.talkdesign.org/faqs/evimmune/ei_animal0
04.jpg
http//www.pelicandivecharters.com/picpages/200401
_jan/images/tunicates.jpg
http//www.geocities.com/robbinknapp/romdap/rplaty
pu.jpg
6
Concept Map
Section 33-1
Chordates
have the followingkey features
which is
A flexiblesupportingstructure
7

• Vertebrates encompass seven classes of animals
• Agnatha (jawless vertebrates)
• Chondrichthyes (cartilaginous fishes)
• Osteichthyes (body fish)
• Amphibia (amphibians)
• Reptilia (reptiles)
• Aves (birds)
• Mammalia (mammals)

• Agnatha
• Only living species are the lampreys and hagfish.
• Have a cartilaginous skeleton and a notochord
  that persists throughout life.
• Lamprey feed by attaching itself to a live fish
  and feed on their blood.
• Hagfish are scavengers.
• Ectothermic

8
Agnatha
http//bioweb.uwlax.edu/zoolab/Table_of_Contents/L
ab-9a/Lampreys/Lab_9a-05a.jpg
http//news.softpedia.com/images/news2/Scientist s
-Will-Use-Pheromones-to-Kill-Lampreys-2.jpg
http//upload.wikimedia.org/wikipedia/en/6/65/Paci
fic_hagfish-300px.jpg
Hagfish
Lamprey
9
Chondrichthyes
www.pbs.org/wnet/ nature/sharks/

• Includes sharks and rays, which have a
  cartilaginous skeleton, paired fins, and biting
  jaws.
• Along each side of a shark is a row of
  microscopic organs sensitive to change in
  surrounding water pressure.
• Reproduce through internal fertilization.
• Have a reproductive tract, excretory system, and
  digestive track.
• Must swim continuously to move water into the
  mouth and out through the gills, necessary for
  respiration and buoyancy.
• Ectothermic

10
Osteichthyes
http//www.cyberdive.org/graphics/cyberdive/bonair
e3/mikki/queenangel.jpg

• This class includes the most species of all
  vertebrates, including all species of fresh water
  and marine fish.
• Have a boney skeleton
• Have an operculum (protective flap) located over
  their gills. This allows them to breath while
  stationary.
• Have a swim bladder, this allows them to adjust
  their buoyancy so they can remain motionless.
• Reproduce through external fertilization (most).
• Ectothermic

Queen Angel
11
Circulation in a Fish
Section 30-2
Gills
Brain and head circulation
Atrium
Sinus Venosus
Oxygen-poor bloodfrom the veins collects in the
sinusvenosus.
Blood enters theatrium and flowsto the
ventricle.
Body muscle circulation
Ventricle
Digestive system circulation
Bulbus Arteriosus
The ventricle pumps blood into the bulbus
arteriosus.
Heart
The bulbus arteriosus moves blood into the
ventral aorta and toward the gills.
12
Figure 3011 The Anatomy of a Fish
Section 30-2
13
Amphibia

• First vertebrates to begin the transition from
  water to land.
• Include salamanders and frogs.
• Most have a larval stage spent in water and an
  adult stage that is adapted for land.
• Most remain close to water
• Must keep skin moist due to inefficient lungs.
• Eggs have no shell and dehydrate quickly in air,
  also they reproduce in moist environments.
  (External fertilization)
• 5. Ectothermic

http//universe-review.ca/I10-82-amphibians.jpg
14
Figure 3026 The Life Cycle of a Frog
Section 30-3
Adult Frog
Adults are typically ready tobreed in about one
to two years.
Young Frog
Frog eggs are laid in water and undergo external
fertilization.
The eggs hatch into tadpoles a few days to
several weeks later.
Fertilized Eggs
Tadpoles
Tadpoles gradually grow limbs, lose their tails
and gills, and become meat-eaters as they develop
into terrestrial adults.
15
Reptilia

• First vertebrates to adapt completely to life on
  land.
• Have scales containing the protein keratin.
• Prevents dehydration and waterproofs the skin.
• Prevents gas exchange, reptiles must rely on
  their lungs for respiration.
• 3. Lay eggs with amniotic fluid on land.
• 4. Ectothermic

http//universe-review.ca/I10-82-reptiles.jpg
16
The Structure of a Turtles Heart
Section 31-1
Liver
Kidney
Heart
Cloaca
Lung
Bladder
Digestivetract
Right atrium
To body
From lungs
To lungs
Left atrium
From body
Ventricle
Incomplete division
17
Figure 318 The Amniotic Egg
Section 31-1
Amnion
Allantois
Embryo
Chorion
Yolk sac
Shell
18
Aves

• Birds are characterized by their many physical
  adaptations that allow them to fly
• honey-combed wings
• Wings
• Minimal organs
• Excellent eyesight
• Endothermic body temperature
• Feathers
• Fat layer
• 4 chambered heart
• Lungs

• 2. Larger brain than reptiles and amphibians.
• 3. Feathers made of keratin.
• 4. Do not chew food, but pass it to their gizzard
  that grinds the food.
• 5. Lay eggs, that are fertilized internally.

19
Figure 3114 The Digestive System of a Pigeon
Section 31-2
Brain
Esophagus
Lung
When a bird eats, food moves down the esophagus
and is stored in the crop.
Heart
1
Kidney
Crop
Air sac
Liver
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.
2
Firstchamberof stomach
Pancreas
Large intestine
Gizzard
Smallintestine
Undigested food is excreted through the cloaca.
Cloaca
5
The muscular walls of the gizzard squeeze the
contents, while small stones grind the food.
3
As digestion continues, the food moves
through the intestines.
4
20
Figure 3116 The Structure of a Birds Heart
Section 31-2
Domestic pigeon
Right atrium
Left atrium
Left ventricle
Right ventricle
Heart
Complete division
21
Mammalia

• Divided into three major groups
• Monotremes which are egg-laying mammals.
  Examples are the platypus and the spiny anteater.
• Marsupials which are mammals with pouches. They
  have a brief gestation period. The do have a
  live birth, but the offspring is very
  undeveloped. It craws and attaches to the nipple
  in the pouch to develop.
• Placental mammals are mammals that the female
  contains a placenta. The placenta is an organ
  that supplies the unborn with nutrients.

• All mammals have
• Hair
• Mammary glands
• Endothermic body temperature
• Diaphragm (muscle between the thorax and abdomen
  to aid in ventilating the lungs.)
• Four chambered heart
• Internal fertilization

22
Compare/Contrast Table
Section 32-2
Orders of Placental Mammals
Order Insectivores Sirenians Cetaceans Chiropter
ans Rodents

Characteristics
Examples
Long, narrow snouts, sharp claws Water-dwelling,
slow-moving Live and breed in ocean, come to
surface to breathe Winged, capable of true
flight Single pair of long, curved incisor teeth
in upper and lower jaws
Shrews, hedgehogs, moles Manatees,
dugongs Whales, dolphins Bats Mice, rats, voles,
squirrels, beavers, porcupines, chinchillas
23
Compare/Contrast Table continued
Section 32-2
Orders of Placental Mammals
Order Perissodactyls Carnivores Artiodactyls Pr
oboscideans
Characteristics
Examples
Hoofed, with an odd number of toes on each
foot Sharp teeth and claws Hoofed, with an even
number of toes on each foot Trunks
Horses, tapirs, rhinoceroses, zebras Tigers,
hyenas, dogs, foxes, bears, raccoons, walruses
Cattle, sheep, goats, pigs, ibex, giraffes,
hippopotami, camels Asian and African elephants,
mastodons and mammoths
24
Compare/Contrast Table continued
Section 32-2
Orders of Placental Mammals
Order Lagomorphs Xenarthrans Primates
Characteristics
Examples
Two pairs of incisors in upper jaw, hind legs
allow leaping No teeth (or very small teeth in
the back of the jaw) Highly developed cerebrum
and complex behaviors
Snowshoe hares, rabbits Sloths, anteaters,
armadillos Lemurs, tarsiers, apes, gibbons,
macaques, humans
25
The Structure of a Bears Heart
Section 32-1
Left atrium
Right atrium
Left ventricle
Right ventricle
Complete division
26
Figure 324 The Jaws and Teeth of Mammals
Section 32-1
CARNIVORE
HERBIVORE
Jawjoint
Jaw joint
Horse
Wolf
27
Comparison of Skulls of Human Ancestors
Section 32-3
Large brow ridge
Large nose
Large canine teeth
Face protrudes forward
Australopithecus afarensis
Homo erectus
Round, high skull
Weak brow ridge
Large brain case
Inflated cheeks
Largenose
Even teeth
Strong chin
Neanderthal
Cro-Magnon
Modern Homo sapiens
28
Figure 3216 Human and Gorilla Skeletons
Section 32-3
Comparing Human and Gorilla Skeletons
Modern Human
Modern Human
Modern Gorilla
Modern Gorilla
Skull atopS-shaped spine Spinal cord exitsat
bottom of skull Arms shorter thanlegs hands do
not touch groundduring walking Pelvis is
bowl-shaped Thigh bones angledinward,
directlybelow body
Skull atopC-shaped spine Spinal cord exitsnear
back of skull Arms longer thanlegs hands touch
ground during walking Pelvis is longand
narrow Thigh bones angledaway from pelvis
29
Figure 332 A Cladogram of Chordates
Section 33-1
30
Figure 334 Diversity of Chordates
Section 33-1
31
Interest Grabber
Section 33-2

• How Hot Is Too Hot?As you know, your body, for
  the most part, maintains a constant temperature.
  Enzymes in your body function most efficiently at
  a temperature that is very close to your body
  temperature.

1. What is the bodys normal temperature? 2.
What happens to your bodys temperature when you
have a viral or bacterial infection? What purpose
might this serve? 3. What do you think would
happen if your body temperature radically
increased or decreased from its normal level?
Explain why.
32
Section Outline
Section 33-2

• 332 Controlling Body Temperature
• A. Body Temperature and Homeostasis
• 1. Ectothermy
• 2. Endothermy
• B. Comparing Ectotherms and Endotherms
• C. Evolution of Temperature Control

33
Body Temperature and Homeostasis

• An endotherm is an animal whose body temperature
  is controlled from within. Birds and mammals are
  endotherms.
• Endotherms tend to have high metabolic rates that
  generate a large amount of heat. Birds use
  feathers (down) as insulation and mammals use fat
  and fur. To get rid of heat, mammals pant and/or
  sweat.

• The control of body temperature is important for
  maintaining homeostasis in vertebrates,
  particularly in habitats where temperature varies
  widely with time of day and with season.
• Ectothermy body temperature is determined by
  the temperature of its environment. Most
  reptiles, fish, and amphibians are ectotherms.

34
Temperature Control in Chordates
Section 33-2
Body Temperature (C)
Environmental Temperature (C)
35
Interest Grabber
Section 33-3

• How Do They Do That?
• As you have read, the problems faced by a
  land-dwelling chordate arevery different from
  those faced by a water-dwelling chordate. Thus,
  the characteristics of these chordates are also
  quite different.
• Choose two chordatesone that lives in the water
  and one that lives on land. Construct a
  compare/contrast table that shows the
  similarities and differences in feeding,
  respiration, movement, and circulation between
  these two chordates.

36
Section Outline
Section 33-3

• 333 Form and Function in Chordates
• A. Feeding
• B. Respiration
• 1. Gills
• 2. Lungs
• C. Circulation
• 1. Single- and Double-Loop Circulation
• 2. Heart Chambers
• D. Excretion
• E. Response
• F. Movement
• G. Reproduction

37
Compare/Contrast Table
Section 33-3
Comparing Functions of Chordates
Respiration Circulation Excretion Response
Gills and diffusion No true chambers Gills
andgill slits Simple mass of nerve cells
Non- vertebrate Chordates Gills and diffusion No
true chambers Gills andgill slits Simple mass
of nerve cells
Gills/air sacs Single loop 2
chambers Kidney andgills Cephalization small
cerebrum
Simple lungs and skin Double loop 3
chambers Kidney andgills Cephalization small
cerebrum
Lungs Double loop 3 chambers Kidney Cephali
zation small cerebrum
Lungs (tubes and air sacs one-way
flow) Double loop 4 chambers Kidney Cephalizatio
n large cerebrum
Lungs (alveoli) Double loop 4
chambers Kidney Cephalization large cerebrum
Birds
Function
Fishes
Amphibians (adult)
Reptiles
Mammals
38
Compare/Contrast Table continued
Section 33-3
Comparing Functions of Chordates
Movement Reproduction TemperatureContr
ol
Muscles,no bones External
fertilization Ectothermic
Muscles on either side of backbone External
fertilization Ectothermic
Limbs point directly toward ground muscles
and ligaments Internal fertilization shelled
egg Ectothermic
Upper limbs are wings 2 feet muscles and
ligaments Internal fertilization shelled
egg Endothermic
2 or 4 legs walk with legs straight under
them muscles and ligaments Internal
fertilization and development Endothermic
Birds
Function
Non- vertebrate Chordates
Fishes
Amphibians (adult)
Reptiles
Mammals
39
Feeding and Digestion

• Teeth break down food physically
• Saliva moisten food and breaks down starches
  into sugars
• Esophagus passes food from the mouth to the
  stomach.
• Stomach Physically digests the food, HCl kills
  bacteria and activates pepsin that begins protein
  digestions.
• Small intestines most digestion and absorption
  occurs.
• Large intestines removes water from the
  undigested food. Vitamin K is produced by
  bacteria.
• Pancreas controls blood sugar levels, produces
  enzymes for digestion and a base to regulate the
  stomach.
• Liver produces bile which breaks down and
  dissolves fat molecules. Gall bladder stores
  the bile.

• Filter feeders have structures to filter
  plankton and other small crustaceans.
• Carnivores have sharp teeth and short digestive
  tracts.
• Herbivores have structures to aid in there
  ingestions and digestion such as flat teeth,
  beaks/bills and long digestive tracts with
  bacteria to aid in breaking down cellulose.

40
Figure 338 The Digestive Systemsof Vertebrates
Section 33-3
Shark
Salamander
Lizard
Pigeon
Cow
Esophagus Stomach Intestine Liver Gallbladder Panc
reas Cloaca Crop Gizzard Cecum Rectum
41
Respiration

• Lungs
• Inhaling brings oxygen rich air from outside the
  body through the trachea and into the lungs. The
  oxygen diffuses into the blood inside the lung
  capillaries. Carbon dioxide diffuses out of the
  capillaries into the air within the lungs.
• Mammals contain alveoli (bubble like structures)
  in the their lungs which increase the surface
  area for gas exchange.

• Gills
• - Water passes over the gill filaments, oxygen
  molecules diffuse into blood in tiny blood
  vessels called capillaries. At the same time,
  carbon dioxide diffuses from blood into the water.

42
Figure 3310 Vertebrate Lungs
Section 33-3
Nostrils, mouth, and throat Trachea Lung Air sac
Salamander
Lizard
Pigeon
Primate
43
Circulation

• - Organisms that use gills for respiration have a
  single-loop circulatory system. Blood travels
  from the heart to the gills, then to the rest of
  the body, and back to the heart in one circuit.
• Organisms that use lungs have a double loop
  circulatory system.
• The first loop carries blood between the heart
  and lungs. Oxygen-poor blood from the heart is
  pumped to the lungs, while oxygen-rich blood from
  the lungs returns to the heart.
• The second loop carries blood between the heart
  and the body. Oxygen-rich blood from the heart
  is pumped from the heart to the body, while
  oxygen-poor blood from the body is pumped back to
  the heart.

44
Heart Chambers

• Crocodilians, Birds and Mammals have a four
  chambered heart.
• -Right atrium receives deoxygenated blood from
  the body
• -Right ventricle pumps the deoxygenated blood to
  the lungs.
• -Left atrium receives oxygenated blood from the
  lungs
• -Left ventricle pumps the oxygenated blood to the
  body

• During the course of evolution, the heart
  developed chambers and partitions that help
  separate oxygenated and deoxygenated blood
  traveling in the circulatory system.
• Fish and larval amphibians have two chambers.
  The atrium receives blood from the body and the
  ventricle pumps the blood to the gills.
• Reptiles have a three chambered heart. Both
  atria empty into the ventricle and some mixing
  occurs.

45
Figure 3311 The Circulatory Systems of
Vertebrates
Section 33-3
Double-Loop Circulatory System
Single-LoopCirculatory System
FISHES
MOST REPTILES
CROCODILIANS, BIRDS,AND MAMMALS
46
Figure 3311 The Circulatory Systems of
Vertebrates
Section 33-3
Double-Loop Circulatory System
Single-LoopCirculatory System
FISHES
MOST REPTILES
CROCODILIANS, BIRDS,AND MAMMALS
47
Excretory System

• Excretory systems release nitrogenous waste from
  the body.
• -Nonvertebrate chordates and fish use gills to
  remove the waste.
• -Most vertebrates rely on kidneys to remove
  wastes from the blood.
• Ammonia is produced and then changed into urea
  before it is excreted by mammals, land amphibians
  and cartilaginous fishes.
• In most reptiles and birds ammonia is changed
  into uric acid.

http//www.faqs.org/health/images/uchr_02_img0199.
jpg
48
Response

• Nonvertebrate chordates have a relatively simple
  nervous system with a mass of nerve cells that
  form a brain. Vertebrates have a more complex
  brain with distinct regions, each with a
  different function.
• The cerebrum the thinking region and
  cerebellum, which controls balance and movement,
  both increase in size and complexity from fishes
  to mammals.

http//www.colorado.edu/epob/epob3730rlynch/image/
figure5-4.jpg
49
Movement and Reproduction

• Almost all chordates reproduce sexually and
  evolution shows a trend from external to internal
  fertilization.
• After fertilization
• -Oviparous eggs develop outside the mothers
  body
• -Ovoviviparous eggs develop inside the mothers
  body and the embryos receive nutrients from the
  yolk in the egg.
• -Viviparous the developing embryos obtain
  nutrients directly from the mothers body.

• The skeletal and muscular systems support a
  vertebrates body and make it possible to control
  movement.
• -With the exception of hagfish, all vertebrates
  have an internal skeleton of bone or cartilage.
• -Ligaments connect the vertebrae
• -Girdles support the fins or limbs.

50
Video Contents
Videos

• Click a hyperlink to choose a video.
• Backbones, Part 1
• Backbones, Part 2

51
Video 1
Video 1
Backbones, Part 1

• Click the image to play the video segment.

52
Video 2
Video 2
Backbones, Part 2
Click the image to play the video segment.
53
Internet
Go Online

• Links from the authors on marine mammals in
  captivity
• Career links on veterinary technicians
• Interactive test
• For links on chordates, go to www.SciLinks.org
  and enter the Web Code as follows cbn-9331.
• For links on homeostasis, go to www.SciLinks.org
  and enter the Web Code as follows cbn-9332.

54
Section 1 Answers
Interest Grabber Answers

• With a partner, identify the characteristic body
  covering for each of the six major groups of
  animals listed below. Then, explain how that
  covering is useful for that group of animals.
• 1. Nonvertebrate chordates tough covering or
  skin provides protection
• 2. Fishes scales (or skin) provides
  protection, reduces friction for locomotion
• 3. Amphibians thin, moist skin allows exchange
  of oxygen and carbon dioxide
• 4. Reptiles dry, scaly skin prevents drying
  out, provides protection
• 5. Birds feathers provide insulation, enable
  birds to fly
• 6. Mammals fur, skin, hair, etc. provides
  insulation and protection

55
Section 2 Answers
Interest Grabber Answers
1. What is the bodys normal temperature? 98.6F
(37C) 2. What happens to your bodys
temperature when you have a viral or bacterial
infection? What purpose might this serve? There
is an increase in the bodys temperature. This
may help to fight whatever agent has invaded the
body because the agents cells function best at
the human bodys normal temperature, not at an
increased temperature. 3. What do you think
would happen if your body temperature radically
increased or decreased from its normal level?
Explain why. Death may occur because the enzymes
that normally catalyze necessary reactions in
your body would have reduced activity or would
not function at all.
56
Section 3 Answers
Interest Grabber Answers

• Choose two chordatesone that lives in the water
  and one that lives on land. Construct a
  compare/contrast table that shows the
  similarities and differences in feeding,
  respiration, movement, and circulation between
  these two chordates.
• Refer to pages 857863 in the textbook for
  possible answers.

57
End of Custom Shows

• This slide is intentionally blank.