Transcript Notes - Unit 2

HUMANITY & THE WORLD BIOMES
Unit 2-2a
The Tundra
Characteristics of
The Tundra
Tundra
Locations
Two
Seasons
Temp
Precip
Biodiveristy
Low
Low
Low
Alaska, Canada, Russia and both poles
Winter: -50oF creates permanently frozen
soil called permafrost
Summer: Just above freezing during the
short growing season
What’s It Like In Barrow, Alaska?
Imagine the
Earth rotating…
Would the north
pole get any
sunlight?
When the Earth’s axis is tilted away from the sun
it is winter & there are 30 days of night at the pole.
But in the summer, with the axis tilted toward the sun,
there are 30 days of sunlight!
Tundra Plants
The tundra is covered in ice most of the year so these
plants survive without deep soil & very little moisture.
Dwarf Willow – World’s smallest tree
(~3” tall) hides from strong winds
Moss Campion – Flowers quickly
& has short hairs on its leaves
Lichen – A producer & a fungus
group that grow on solid rock
Cotton Grass – Their fluffy white
seeds are easily carried by wind
Why are evergreen trees not found in the tundra?
Tundra Animals
How do animals survive the extreme conditions of the tundra?
Arctic Fox – The short legs, ears & muzzle help conserve
heat; Seasonal fur color
Caribou – Large hooves support
them in marshes & snow
Polar Bear – Dark skin and clear
fur absorb the sun’s rays
Penguin – Camouflage coloring and
fatty blubber help when swimming
Which adaptations are shared between these species?
Let’s Review…
What have you learned in this unit?
1. Describe the temp, precipitation
and biodiversity of the tundra.
2. Where are tundra located?
3. How many hours of daylight
does the tundra receive during
each season?
4. What adaptations have plants
developed to live in permafrost?
5. Name two animal adaptations
for the tundra.
HUMANITY & THE WORLD BIOMES
Unit 2-2b
The Savanna
Characteristics of
The Savanna
Savanna
Locations
Two
Seasons
Temp
Precip
Biodiveristy
High
Average
Average
South Africa, India & Australia
Dry: Long periods without rain (droughts)
Wet: Monsoons bring up to 20” of rain
How Is The Savanna Maintained?
Grasses dominate the
savanna because…
• Frequent droughts
• Many grazing animals
• Naturally-occurring
fires are common
These factors prevent larger plants from growing!
Savanna Plants
Bermuda Grass – Deep root system that stores water and
can easily re-grow after fires
Elephant Grass – Grows 10 ft
tall with razor-sharp blades
Senegal Gum – Thorny tree with
sap that makes several medicines
Candelabra Tree – Has a sticky,
poisonous sap that causes blisters
Do all of these plants share a common adaptation?
Savanna Animals
Due to droughts, these animals have strong legs
to support migration over great distances.
African Elephant – Long trunk for reaching;
Large, thin ears that dissipate heat
Zebra – Stripes to confuse predators;
Strong hooves for protection
Wild Dog – Large ears and a
multicolored coat
Kangaroo – Pouch for infants;
Powerful legs for jumping
Which adaptations do impalas have to help them survive?
Let’s Review…
What have you learned in this unit?
1. Describe the temp, precipitation
and biodiversity of the savanna.
2. Where are savannas located?
3. Which three factors prevent
grasslands from becoming forests?
4. List two plant adaptations for
the savanna.
5. List two animal adaptations for
the savanna.
HUMANITY & THE WORLD BIOMES
Unit 2-2c
Integumentary Adaptations
The Integumentary System
Comprised of skin, hair & nails
Hair & Nails – Offer protection & insulation; Have
keratin, a protein which makes cells tough & waterproof
Skin - Protects from infection & dehydration; Maintains
body temperature
• Epidermis - Outer layer of
dead skin with keratin
• Dermis - Has nerves, hair
follicles, sweat glands and
blood vessels
• Subcutaneous Layer - Deepest layer of fatty tissue
How does the subcutaneous layer help you?
Look At These People
Which parts of the integumentary system are visible?
Skin
Hair
Nails
The Eyes
What can you see that
is not part of the integumentary system?
Shades of Skin Color
Melanin – A pigment in the skin that protects you from UV
radiation
Darker skin, offer more protection
from the sun’s rays.
Lighter skin, allows for increased
production of Vitamin D.
Albino people cannot produce pigment.
Von Luschan’s Chromatic Scale
1
5
10
15
20
25
30
36
Integumentary System Diseases
Skin Cancer – A genetic mutation that’s caused by overexposure to UV radiation. Cancer is uncontrolled cell division.
The ABCD’s of
skin cancer
Two types:
not uniform
Carcinoma – More common and affects non-pigment producing
cells; Can be successfully treated
Melanoma – Less common and affects pigment producing cells;
Spreads quickly and is often fatal
Other Skin Adaptations
The average core body temperature is about 98.6°F,
To prevent hypothermia (<94°F) in extreme cold…
• Skin shivers creating warmth by muscle movement
• Goosebumps make hairs stand up to trap warm air
• Decreased blood flow to extremities (ex: fingers, toes,
ears & nose) to preserve core body temperature
What’s this called?
Other Skin Adaptations
To prevent hyperthermia (>105°F) in extreme heat…
• Skin sweats cooling the body as it evaporates
• Increased blood flow to extremities helps release heat
• Reduced urination & sweating before death
Let’s Review…
What have you learned in this unit?
1. What three parts of the body
make up the integumentary system?
2. What is the name & function
for each layer of our skin?
3. What are the results of higher
and lower levels of melanin?
4. Explain how a person can get
skin cancer & the symptoms of it.
5. How does our skin react to
extreme temperatures in order to
regulate body temperature?
Dust Mite & Dead Skin
HUMANITY & THE WORLD BIOMES
Unit 2-2d
Musculoskeletal Adaptations
The Skeletal System
There are 206 bones in an adult offering
protection, gives us shape & enables movement.
The skeleton is divided into…
• Axial – Makes up the skull and trunk
• Appendicular – Makes up the limbs
A Joint, where two bones meet,
includes…
• Ligaments – Hold two bones together
• Tendons – Attach muscle to the bone
What is the purpose of the cartilage in your knee?
Muscle Movement
How do muscles open & close your arm?
Muscles always work together in pairs.
Each contracts in opposite
directions for movement.
Identify these for
your elbow…
Extensor - A muscle that
opens a joint; Triceps
Flexor – A muscle that
closes a joint; Biceps
These muscles create motion in all parts of your body
including your wrist, jaw, neck, and even eyelids.
Skeletal System Diseases
Osteoporosis – Porous & brittle bones; Can be prevented
through proper nutrition
Arthritis – Wearing away
of cartilage causing painful
bone on bone contact
Where do blood cells form?
Leukemia – Blood cancer caused
by defective blood cells formed
in the bone marrow
Calcium absorption reduces dramatically after age 35 so…
Start Building Strong Bones Today!
Musculoskeletal Adaptations
People native to polar biomes generally have…
• Stockier bodies with shorter limbs
• Higher percentage of body fat
• Flatter faces with smaller features
In which part of the world are Inuit people located?
Musculoskeletal Adaptations
People native to tropical biomes generally have…
• Taller, slender bodies
• Carry very little fat
In which part of the world
are Tutsi people located?
Let’s Review…
What have you learned in this unit?
1. Why do babies have so many
more bones than adults?
2. Name one bone in both the axial
and the appendicular skeleton.
3. What steps can you take to
reduce the risk of bone disease?
4. Estimate how many different
muscles control your neck motion.
5. Describe the most successful
body types for surviving at the
poles & the equator.