1. Inheritance Why we look the way we do.

2. We look the way we do because we inherit certain
traits from our parents, from the texture of our
hair to the color of our eyes.
All these traits that make up how we look are carried
in our DNA (deoxyribonucleic acid).

3. Where is DNA found?
DNA is found in the nucleus
of the cell.

4. The Role of Genes in Inheritance
Chromatin is in the nucleus of a cell
Chromatin forms into chromosomes during cell replication
Chromosomes are partly composed of DNA
Do NOT
put this on internet!
Source of photos: Mitosis Stages

5. What is DNA? DNA is genetic material
DNA carries information about an organism that is passed from parents to offspring
Some of the DNA in chromosomes consists of genes

6. A gene is found on a chromosome. A chromosome contains many genes.

7. What is a Gene?
A gene is a section of DNA that controls a trait that an organism inherits
Genes are like recipes. Just as a recipe contains instructions for preparing food, genes contain instructions for building and running cells.

8. Sexual Reproduction
Two parents supply genetic material that determines the characteristics of their offspring. (In other words, each parent supplies genes that determine the traits of the offspring.)
In sexual reproduction, the offspring will not be identical to the parents.
(In asexual reproduction, which involves only one parent, you’ll remember, the offspring will be identical to the parent.)
Where do we see asexual reproduction?

9. How are Traits Expressed in the Offspring?
An offspring receives traits from both parents
Dominant traits hide recessive traits. In other words, even if an offspring receives one dominant and one recessive trait, the offspring will express only the dominant trait.
Recessive traits are only expressed when provided by both parents. In other words, the offspring must receive recessive traits from both the male and female parent. If either parent passes on a dominant trait, the recessive trait will be hidden!

10. Bent pinky Pinkies lean away from each other: dominant
Pinkies lean toward each other: recessive

11. Thumbs: Straight thumb (dominant trait) vs
Thumbs: Straight thumb (dominant trait) vs. Curved thumb (recessive trait) When viewed from the side as in the illustration below, curved thumbs can be seen as part of a circle.

13. Tongue Rolling
Tongue Roller
Not a Tongue Roller

14. Hairline
Widow’s peak
Straight hairline

15. Chin
Cleft Chin
No Cleft Chin

16. Long toes
Second toe longest
Big toe longest

17. Are you an alien?

18. Are any of these traits learned?
Traits are inherited, not learned. Behavior is
learned.

19. Inherited or Acquired? Behavior is the way animals act and react
Instinct is a form of behavior animals are born with.
Other animal behaviors are learned or acquired through experience or study.
Birds know how to build a nest. That is an instinct.
Birds learn how to fly. Their parents teach them. That is a learned or acquired behavior.

20. Instinct or Acquired? Birds fly south for the winter.
Salmon swim miles upstream against strong currents to lay their eggs.
A bee stings its enemies.
An animal avoids an electrified fence.
A caterpiller spins a cocoon.
A raccoon stands perfectly still if it senses danger.
S.M.Willingham

21. Instinct or Acquired? An armadillo jumps straight up when surprised.
A child says “please” and “thank you” at appropriate times.
A dog sits before getting a treat.
A black bear hibernates in the winter.
A robin gathers food to feed her young.
A sea lion balances a ball on the tip of its snout
A cat drinks water when it is thirsty.
S.M.Willingham

22. DOMINANT OR RECESSIVE?
FREE ATTACHED

23. Brown eyes are dominant.
Colored eyes are recessive.

24. Genetic Traits Earlobes: Free ear lobes (dominant trait) vs
Genetic Traits Earlobes: Free ear lobes (dominant trait) vs. Attached ear lobes (recessive trait) Free earlobes are those that hang below the point of attachment to the head. Attached ear lobes are attached directly to the side of the head.

25. Hand clasping Left thumb on top: dominant
Right thumb on top: recessive

26. Dimples: Dimples (dominant trait) vs
Dimples: Dimples (dominant trait) vs. No dimples (recessive trait) Dimples are natural dents in the face to the right or left of the mouth. If a person has only one dimple, they should be counted as having dimples.