HUMANITY & THE WORLD BIOMESHUMANITY & THE WORLD BIOMES

Unit 2-2aUnit 2-2a

The TundraThe Tundra

Characteristics Of The Tundra

Locations – Tundra can be found at both poles and at the top of the tallest mountains.

Abiotic Factors

• Temperatures range from just above freezing in the summer to -50oF in the winter.

• In the summer, the top of the permanently frozen soil called permafrost thaws to create some moisture during the short growing season.

TundraTemperatu

rePrecipitati

onBiodiversit

y

Low Low Low

What’s It Like In Barrow, Alaska?

Imagine theEarth rotating…

Would the north pole get any

sunlight?

When the Earth’s axis is tilted away from the sunit 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

Because the tundra is covered in ice, these plants must survive without deep soil and very little moisture.

Dwarf Willow – World’s smallest tree(~3 in tall) hides from strong winds

Moss Campion – Flower veryquickly and have short hairs ontheir leaves for insulation

Lichen – A composite organismof a producer & a fungus thatcan grow on solid rock

Why aren’t there any evergreen trees 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; It’s fur changes color with the seasons.

Caribou – Have large hooves thatsupport them in marshes & snow;Shorter legs & seasonal fur color.

Polar Bear – Has dark skin and clearfur to absorb the sun’s rays; Thickblubber & webbed feet to swim.

Penguin – Black & white color forcamouflage while swimming underwater.

Do all of these animals share a common adaptation?

Close Your Notebooks… What have you learned in this unit?

1. Describe the temp, precipitationand biodiversity of the tundra.

2. Where are tundra located?

3. How many hours of daylightdoes the tundra receive duringeach season?

4. What adaptations have plantsdeveloped to live in permafrost?

5. Name two animal adaptationsfor the tundra.

HUMANITY & THE WORLD BIOMESHUMANITY & THE WORLD BIOMES

Unit 2-2bUnit 2-2b

The SavannaThe Savanna

Characteristics Of The Savanna

Locations – Savannas are tropical grasslands located near the equator in Africa, India, Australia & South America.

Abiotic Factors

• Temperatures average between 80-90oF all year. There are two seasons – wet & dry.

• While most of the year is dry, the wet season brings monsoons with ~20 inches of heavy rains.

SavannaTemperatu

rePrecipitati

onBiodiversit

y

High Average Average

How Is The Savanna Maintained?

Grasses dominate thesavanna because…

• Grazing animalseat significantly eachday,

• Droughts are commonand,

• Naturally-occurringfires are frequent

And these factors prevent larger plants from growing

Forests generally need at least 55 inches of rain/year

Savanna Plants

Bermuda Grass – Has a deep root system that stores water during droughts and helps it re-grow after fires.

Elephant Grass – Can grow 10 fttall with razor-sharp blades.

Senegal Gum – A thorny tree withsap that makes several medicines

Candelabra Tree – Has a sticky,poisonous sap that causes blisters

Which two survival strategies are used by these plants?

Savanna Animals

Due to droughts, savanna animals have strong and/or long legs to support migration over great

distances.

African Elephant – Long trunk for reaching; Large, thin ears that wave to dissipate heat.

Zebra – Stripes to confuse predators;Thick hooves for defensive kicking

Wild Dog – Large ears; Strong legs;Multicolored camouflage coat

Kangaroo – Pouch for developing young;Powerful legs for jumping

Do all of these animals share a common adaptation?

Close Your Notebooks… What have you learned in this unit?

1. Describe the temp, precipitationand biodiversity of the savanna.

2. Where are savannas located?

3. Which three factors preventgrasslands from becoming forests?

4. List two plant adaptations forthe savanna.

5. List two animal adaptations forthe savanna.

HUMANITY & THE WORLD BIOMESHUMANITY & THE WORLD BIOMES

Unit 2-2cUnit 2-2cIntegumentary Integumentary

AdaptationsAdaptationsTo Extreme BiomesTo Extreme Biomes

The Integumentary SystemComprised of hair, nails & skin

Hair & Nails - Protection & insulation. Made from mostly keratin which makes cells tough & waterproof.

Skin - Protection from infection, injury & dehydration;Maintains body temperature.

• Epidermis - Outer layer of skin; Dead, flat cells of keratin.

• Dermis - Lined with nerve cells, hair follicles, sweat glands andblood vessels.

• Subcutaneous Layer - Deepest layer of fatty tissue that insulates, cushions & stores nutrients.

Look At These People

Which parts of the integumentary system are visible?

Skin

Hair

Nails

The Eyes

What can you see thatis not part of the integumentary system?

Shades of Skin Color

Melanin – A pigment created by the inner layer of the epidermis that protects the skin from UV radiation.

Higher levels of melanin, producingdarker skin, offer more protectionfrom the sun’s rays.

Lower levels of melanin, producinglighter skin, allow for increasedproduction 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 over- exposure to UV radiation.

The ABCD’s of skin cancer

Carcinomas – A more common condition affecting non- pigment producing cells. It can be successfully treated.

Melanomas – A more rare cancer affecting pigment producing cells that spread quickly and accounts for the majority of skin cancer deaths.

not uniform

Other Skin AdaptationsThe average core body temperature is about

98.6°F,

To prevent hypothermia (<94°F) in extreme cold…

• The skin shivers creating warmth by muscle movement

• Goosebumps make hairs stand up to trap warm air

• Blood flow to the extremities (includes fingers, toes, ears & nose) reduces to preserve core body temperature

What’s this called?

Other Skin Adaptations

To prevent hyperthermia (>105°F) in extreme heat…

• The skin sweats, cooling the body as it evaporates

• Blood flow to the extremities increases, releasing heat from the body

• In serious cases, the body reduces urination & sweating

Close Your Notebooks… What have you learned in this unit?

1. What three parts of the bodymake up the integumentary system?

2. What is the name & functionfor each layer of our skin?

3. What are the results of higherand lower levels of melanin?

4. Explain how a person can getskin cancer & the symptoms of it.

5. How does our skin react toextreme temperatures in order toregulate body temperature?

Dust Mite & Dead Skin

HUMANITY & THE WORLD BIOMESHUMANITY & THE WORLD BIOMES

Unit 2-2dUnit 2-2dMusculoskeletal Musculoskeletal

Adaptations To Extreme Adaptations To Extreme BiomesBiomes

The Skeletal System

There are 206 bones in an adult (350 in an infant) that provides 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,functions due to…

• Ligaments – Hold two bones together

• Tendons – Attach muscle to the bone

What is the purpose of the cartilage?

Skeletal System Diseases

Osteoporosis – Porous and brittle bones in people Can be prevented through proper nutrition.

Arthritis – Diseases that wearaway cartilage causing painfulbone on bone contact.

Leukemia – Blood cancer in whichan overabundance of defectiveblood cells are formed in the bone marrow

Calcium absorption reduces dramatically after age 35 so…

Start Building Strong Bones Today!

How Do Muscles Your Arm Move?

Muscles always work together in pairs.Each pull in opposite directions to create

movement.

Which muscles contractto open & close your arm?

Extensor - A muscle that opens a joint.

Flexor – A muscle thatcloses a joint.

Identify these…

These muscles create motion in all parts of your body including your wrist, jaw, neck, and even

eyelids.

Joint Extensor Flexor

Elbow Triceps Biceps

Musculoskeletal Adaptations

People native to polar biomes generally have…• Stockier bodies with shorter limbs• Higher percentage of body fat• Flatter faces without extruding features

How do these strategies help people survivein polar biomes?

Musculoskeletal Adaptations

People native to tropical biomes generally have…

• Taller, slender bodies• Carry very little fat

How do these strategies help people survive in tropical biomes?

Close Your Notebooks… What have you learned in this unit?

1. Why do babies have so manymore bones than adults?

2. Name one bone in both the axialand the appendicular skeleton.

3. What steps can you take toreduce the risk of bone disease?

4. Estimate how many differentmuscles control your neck motion.

5. Describe the most successfulbody types for surviving at thepoles & the equator.