Transcript Animals - Killeen ISD

Unit 12: Animal Systems
Why is a sponge even an animal?
The “Big 5” for Animals
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Multicellular
Eukaryotic
Heterotrophic
Motile
No cell walls
Organ systems work together
Why do animals need these?
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Muscular – movement
Skeletal – support; what muscles pull on
Circulatory – transport of substances
Nervous – control
Immune – fight disease
Why do animals need these?
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Respiratory – gas exchange
Endocrine – control (hormones)
Digestive – break down food
Urinary – remove cell wastes
Reproductive – produce offspring
Invertebrate Evolution
I can haz cheezburger?
(Animals like to eat!)
• Intracellular digestion
– Within individual cells;
food must be tiny
– Ex: only sponges do this…it
was quickly improved upon!
• Extracellular digestion
– Within separate cavity
(gut), then absorbed into
cells; ex: all other
animals!
Symmetry =
complexity of motion & nerve control
• Asymmetry
– No symmetry
– ex:sponges: non-motile – why bother?)
• Radial Symmetry
– No front/back, only top/bottom
– Ex: jellyfish (float…no need for a “face”
• Bilateral Symmetry
– Front/back/top/bottom (a “face”)
– Ex: most other animals
• Cephalization – having a head
region
Symmetry =
complexity of motion & nerve control
• Bilateral Symmetry
– Nerves allow for movement and
sensory input
• Cephalization – is the
centralization of nerve tissue to
the head region
• Allows better movement
• Leads to brain eventually
Mouth + Anus = Yes!
(good job, nematodes!)
• Incomplete digestive system
– Only one opening; inefficient!
– Ex: jellyfish & flatworms
• Complete digestive system
– Two openings (mouth & anus)
– Ex: all other animals!
Invertebrate Evolution
Brains!
• Allow for maximum control
of movement and sensory
input/analysis
Segmentation
• Segments and
compartments allow for
specialization
• Having body sections =
don’t have to keep doing
same body function all the
way through the body
Skeletomuscular System
• Muscles allow for movement, but only work if
they have something rigid to pull on
• Accomplished in varied ways throughout the animal
world
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Water-filled tubes (worms,starfish)
Shells (snails, oysters)
Exoskeleton (insects, crustaceans)
Endoskeleton (bones in vertebrates)
Appendages (with joints!)
Includes arms, legs,
antennae, pincers, etc
Allows for better…
• movement
• prey capture
• sensation
Invertebrate Evolution
Body Coverings (Integument)
• Quite diverse - adapted for varied habitats
and temperature control
– What are each of these well-adapted to?
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Scales
Soft, moist skin
Dry, scaly skin
Feathers
Hair/fur
Fertilization – Two Strategies
• External Fertilization
– usually in water (why?)
– usually larger #s of offspring (why?)
– usually low parental care (why?)
• Internal Fertilization
– usually smaller #s of offspring (why?)
– usually more parental care
Adaptations for Land
• Fins and flippers for motility
– Why wont this work on land? How to fix it?
• Limbs (arms/legs)
• Gills for gas exchange
– Why wont this work on land? How to fix it?
• Lungs – air sacs that diffuse gases into blood
• Scales for covering
– Why wont this work on land? How to fix it?
• Skin (continuous covering across body)
Amphibians “invent” all of these
Adaptations for Land
• But, amphibians are still tied to water…why?
– Gelatinous eggs (like fish)…so why a problem? How to fix?
• Amniotic Egg
– Invented by reptiles; Allows for fully living on land
– Embryo protected within membranes & shell
– Mammals take this a step further by keeping embryo inside
the mother (but same idea!)
Temp. Control – Two Strategies
Ectotherms
• Regulate body heat using
surroundings (environment)
• This limits their habitats (no
extremes)
• Better in aquatic habitats
(why?)
• Ex: fish, amphibians, reptiles
Endotherms
• Make own body heat – how?
• Costs much more energy
(food)
• Allows for more varied
habitats
Temperature
• Why is regulating temperature so important?
• Denaturing proteins – broken if too hot
• Metabolism rates (Q10) higher with heat
Circulatory System
• All vertebrates and large invertebrates have
blood vessels - Why?
– Open circulatory system = no vessels
– Closed circulatory system = with vessels
Circulatory System
• Heart used to pump blood through the body
– Fish use 2-chambered hearts
• But allows O2-blood to mix with the de-O2 blood –
NOT EFFICIENT (but good enough for them)
– The best heart has 4 chambers
• Keeps the “good” and “bad” blood totally separate
• Provides maximum amount of oxygen (especially
important for endotherms and large animals!)
Circulatory System
DIFFUSION
Surface Area & Thin Membranes
Body systems rely on materials being able to move from one
area to another.
- why is a thin layer of cells better?
- why is more surface area better?
Circulatory system links all systems!
- capillaries (tiny blood vessels) are thin, so diffusion is easy
- wherever diffusion takes place…capillaries are there!
More SA = More Exchange
Small intestines
(villi & microvilli)
Lung
(alveoli)
DIFFUSION across Membranes
Digestive
- food broken down in tube…mostly absorbed into
bloodstream at small intestine
- nutrients diffuse from thin VILLI to CAPILLARIES
DIFFUSION across Membranes
Respiratory
- O2 passes thru thin ALVEOLI to CAPS
- CO2 passes thru CAPS to ALVEOLI
DIFFUSION across Membranes
Urinary
- wastes move from
CAPS to NEPHRONS
in kidney
What do ALL of these
have in common?
HOMEOSTASIS
All organisms require a stable internal environment.
• If something is too low, it’s usually fixed by …?
• Why can’t the organism just get the value to the right
spot and just leave it there?
- cells use up glucose, O2 continuously
- wastes are constantly created
Stimulus  Control Center  Response
Sense
 Decide
 Respond
Negative Feedback
What is the
stimulus?
What is the
response?
Negative Feedback
• How do the stimulus and the response
relate to each other?
The stimulus and
response go in
OPPOSITE
directions.
Negative Feedback:
Blood Glucose
• Insulin
– Reduces glucose
• Glucagon
– Increases glucose
How will you know
this is negative feedback
when you see it?
Positive Feedback
• How will stimulus and response relate for
this type of feedback?
The stimulus and
response go in
the SAME
direction.
• Do you think this is more or less common
than negative feedback? Why?
Positive Feedback
• Pressure on uterus  oxytocin hormone
released  it tells uterus to contract more 
more pressure  more oxytocin  more…
• When does the reaction end?
Digestive System
• Job = break down and absorb
food molecules
• Most chemical digestion and
absorption happens in small
intestine
• Absorption of molecules
– Villi of Small Int blood capillaries
Digestive System
• Homeostasis =
stimulus = stomach empty, ghrelin released
response = hungry feeling
Respiratory System
• Job = breathe (air in/out) and gas exchange (O2 &
CO2 to/from blood)
• Diaphragm contracts to pull in air (inhale)
• Gas exchange
– Alveoli of lungs  blood capillaries
Respiratory System
• Homeostasis
Stimulus = too much CO2 (more acidic/low pH)
Response = breathe more (exhale CO2)
Endocrine System
• Job = control body functions using hormones
• Hormones = chemical signals that control body
functions
• Useful for “not instant” reactions (takes minuteshours to get a response)
• Involves negative or
positive feedback
Endocrine System
• Notice general
location of glands
– Will focus on
hormones related to
digestive and
reproductive systems
– Which organs will that
be?
Endocrine System: Blood Glucose
Pituitary
Oxytocin
- Pair-bonding
- Uterine contractions
– Lactation
Growth Hormone (GH)
– Growth (bone, etc)
Endocrine System: Blood Glucose
Pancreas
• Insulin
– Reduces blood-glucose
(stores it in liver)
• Glucagon
– Increases blood-glucose
(pulls it from liver)
Timing of reproductive events controlled
by the Endocrine System
• Occurs through whole life, not just at puberty!
– ex: growth hormone (GH) lets you grow!
• Puberty – hormones from pituitary activate
– signal testes/ovaries to start making mature
gametes, and produce sex hormones
– Males (Testes) = testosterone
– Females (Ovaries)
– estrogen & progesterone
Testosterone
- Signals testes to make sperm cells
- Allows for male secondary sex characteristics
Estrogen
Signals ovaries to get
egg ready
- Allows for female
secondary sex
characteristics
Progesterone
- Prepares uterine lining
to accept embryo
- Shed if no
implantation
Fertilization & Implantation
Why does
fertilization
have to happen
so far up in the
tube?
At what point
does pregnancy
occur?
Fertilization
It takes many
sperm to release
enough enzymes to
break through the
eggs covering
But, only ONE
sperm may actually
enter the egg
Cell Cleavage (Mitosis)
Fetal Development
5 weeks
14 weeks
20 weeks
Stages of Birth
Immune System
• Job = protect body from
foreign invaders
• Nonspecific defenses =
try to block everything
• Ex: skin, fever, inflammation,
secretions (oil, sweat, acid,
mucus, etc)
Immune System
• Specific defenses = fights against particular bad
guys
• Ex: T-cells & B-cells and antibodies
– recognize specific pathogens and build killer
army just to fight that
Circulatory System
• Job = transport substances
throughout body (links all
systems)
• Heart pumps blood
• Arteries, veins, &
capillaries carry blood
• Exchanges happen
through capillaries
System Interactions: Energy Production
On the cellular level, why do animals need to eat?
What system gets the food?
To burn that glucose, what gas do they need?
What system gets the oxygen?
How does the oxygen get to cells?
What system carries the blood?
Once burned, cells forms wastes…gas & liquid.
What gas? How is it carried out? Where does it exit?
What liquid? How is it carried? Where does it exit?
The End
Quiz – Animals #1
• 1. Explain TWO reasons why sponges are a
sorry excuse for an animal.
• 2. Sponges are very different from most
animals. Why are they even classified as
animals?
Quiz – Animals #1
• 3. All of the following are advantages provided
by cephalization EXCEPT – A. better surface on which muscles can pull
– B. better sensory control to detect stimuli
– C. allows for formation of brain tissues
– D. directional motility
Quiz – Animals #1
• 4. Jellyfish solve the problem of __, but still
have a problem because they __
– A. having no nerve tissue
…cannot digest large food particles
– B. intracellular digestion
…only have one digestive opening
– C. the incomplete digestive tube
…cannot break down proteins
– D. having no head region
…are asymmetric
Quiz – Animals #1
• 5. The animals shown in the picture below are
limited in their choice of habitats because –
– A. Their brains are tiny
– B. They have an endoskeleton of bone
– C. They do not produce very many gametes
– D. Their eggs dry out in the air
Quiz – Animals #1
• 6. Which reproductive
strategy applies to the
animals shown here?
– A. Spend no energy on reproduction
– B. Spend little energy making babies, but lots of
energy protecting the young
– C. Spend lots of energy making gametes, but no
energy raising the babies that form
– D. Spend lots of energy producing many gametes
and protecting the babies that form
Quiz – Animals #1
• 7. Invertebrates with brains, segmentation,
and jointed appendages would most likely be A. Molluscs
B. Annelids
C. Arthropods
D. Nematodes
• 8. An invertebrate that has segments but lacks
an exoskeleton would most likely be a(an) A. Jellyfish
B. Sponges
C. Snails
D. Earthworms
Quiz – Animals #1
• 9. Complete the analogy Gymnosperms: Seeds :: Reptiles: ___
A. Amniotic eggs
B. Internal fertilization
C. Scaly skin
D. Ectothermy
• 10. Which has the most difficulty regulating its
body temperature on a daily basis?
A. goldfish
B. lizard
C. parrot
D. mouse
Grade It!
• Switch books
• Only mark it if it is wrong
• Write grade at top and circle it
Quiz – Animals #1
• 1. Explain TWO reasons why sponges are a sorry excuse for
an animal.
– Non-motile (mostly) -- no head region/bad motion
– Intracellular digestion -- no gut/ no digestive system
• 2. Sponges are very different from most animals. Why are
they even classified as animals?
– Multicellular – Heterotrophic – No cell wall
OR
– Multicellular – No cell wall
OR
– Heterotrophic – Motile (larvae)
OR
– Multicellular – Motile (larvae)
Quiz – Animals #1
• 3. All of the following are advantages provided
by cephalization EXCEPT – A. better surface on which muscles can pull
– B. better sensory control to detect stimuli
– C. allows for formation of brain tissues
– D. directional motility
Quiz – Animals #1
• 4. Jellyfish solve the problem of __, but still
have a problem because they __
– A. having no nerve tissue
…cannot digest large food particles
– B. intracellular digestion
…only have one digestive opening
– C. the incomplete digestive tube
…cannot break down proteins
– D. having no head region
…are asymmetric
Quiz – Animals #1
• 5. The animals shown in the picture below are
limited in their choice of habitats because –
– A. Their brains are tiny
– B. They have an endoskeleton of bone
– C. They do not produce very many gametes
– D. Their eggs dry out in the air
Quiz – Animals #1
• 6. Which reproductive
strategy applies to the
animals shown here?
– A. Spend no energy on reproduction
– B. Spend little energy making babies, but lots of
energy protecting the young
– C. Spend lots of energy making gametes, but no
energy raising the babies that form
– D. Spend lots of energy producing many gametes
and protecting the babies that form
Quiz – Animals #1
• 7. Invertebrates with brains, segmentation,
and jointed appendages would most likely be A. Molluscs
B. Annelids
C. Arthropods
D. Nematodes
• 8. An invertebrate that has segments but lacks
an exoskeleton would most likely be a(an) A. Jellyfish
B. Sponges
C. Snails
D. Earthworms
Quiz – Animals #1
• 9. Complete the analogy Gymnosperms: Seeds :: Reptiles: ___
A. Amniotic eggs
B. Internal fertilization
C. Scaly skin
D. Ectothermy
• 10. Which has the most difficulty regulating its
body temperature on a daily basis?
A. goldfish
B. lizard
C. parrot
D. mouse
Quiz – Animals #1
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