GENETICS AND ADAPTATIONS

INHERITED VS. ACQUIRED TRAITS What is an acquired trait?

A trait that an organism acquires or gains over its lifetime. It cannot be passed on to its offspring. Like the ability a monkey has to peel a banana.

What is an inherited trait? A trait that is passed to offspring because of

genetic inheritance. Could be good or bad for the organism.

INHERITED TRAITS What are some examples of traits that

make an organism MORE suited to its environment?

What are some examples of traits that make an organism LESS suited to its environment?

INHERITED OR ACQUIRED? Blue eyes

Dog’s short fur

Broken arm

Blonde hair

A Cold

Sun tan

Colorblindness

Ability to roll tongue

Love of music

Ability to do math well

LAMARCK When environments changed, organisms

had to change their behavior to survive. If they began to use an organ more than they had in the past, it would increase in its lifetime. If a giraffe stretched its neck for leaves, for example, a "nervous fluid" would flow into its neck and make it longer. Its offspring would inherit the longer neck, and continued stretching would make it longer still over several generations. Meanwhile organs that organisms stopped using would shrink.

Is this true?

TOOTHPICK ACTIVITY In your group of 3, time each person for

10 seconds while they pick up toothpicks one by one.

Make a chart in your notes of how many toothpicks of each color each person picked up.Person Brown Red Yellow

Leonardo

Donatello

Michaelangelo

BUTTERFLIES Count how many butterflies you can

spot on the wall

Count how many butterflies you can spot on the floor

HOMEWORK Write down 5 adaptations animals have

that help them survive in their environment.

Write down 5 traits that you have inherited from your parents.

HOW ARE TRAITS PASSED ON? Two ways to inherit traits. Most

organisms reproduce with one or the other, not both.Asexual reproductionSexual reproduction

Both use genetic information (DNA) to create offspring

ASEXUAL REPRODUCTION The DNA of the parent is the same as

the offspring.

Any genetic mutation (whether good or bad) will be passed onto the offspring.

BACTERIA

SOME PLANTS

ALGAE

MARINE LIFE

HYDRA

PLANERIA

FUNGI

SEXUAL REPRODUCTION A better system for producing genetic

variation and therefore “fitness” for an environment

½ of the DNA from one parent and ½ from the other parent

SEXUAL REPRODUCTION Advantages

More opportunity for mutationsMore DNA combinations

DisadvantagesSometimes takes longerSome bad genes are still possible

MAMMALS

BIRDS

FISH

REPTILES

DNA Double ½ genes on one side ½ genes on other side Sex cells have ½

DNA ACTIVITY Read pg C97-103 as a class.

Make an example of an offspring’s DNA in asexual and sexual reproduction.

Follow the example on the board.