This document summarizes dominant and recessive traits in heredity. It explains that traits are passed from parents to offspring through chromosomes and alleles. Examples of physical and behavioral traits are given. Dominant traits will be expressed if present, while recessive traits are masked by dominant alleles. The document uses eye color as an example trait, with brown as dominant and blue as recessive. It shows how a Punnett square can be used to determine possible offspring genotypes and phenotypes based on parental alleles. The document provides links to additional online resources on inheritance and traits.

1. Step 3: Identify examples of dominant and recessive traits in humans and other
living things
https://www.youtube.com/watch?v=TGLYcYCm2FM

2. The passing of traits from parents to child is the basis of
heredity
What are examples of Traits?
Physical Traits: Characteristics of one's physical makeup like
hair colour, eye colour, and height
Behavioral Traits: Characteristics of the way one acts

3. How do we get traits from our parents?
46
46
23
23
46
Father
Mother
sperm
egg
Zygote = New Individual
numbers in the circles
are the number of
chromosomes
http://learn.genetics.utah.edu/content/inheritance/intro/ (3 clicks)

4. Why aren't biological siblings exactly the same?
Our 46 chromosomes are a random combination from our mother and father. Our
brother's or sister's 46 chromosomes
are a different random combination from our mother and
father
(4 + clicks)

5. http://learn.genetics.utah.edu/content/inheritance/traits/

6. When traits are passed on to new individuals, what are the
possibilities?
http://learn.genetics.utah.edu/content/inheritance/traits/
for each trait, there are 2 alleles (possibilities)
ex) hitchhiker's thumb and straight thumb. The
alleles are represented by capital and lower case
letters.
"h" "H"
(Thumb trait)

7. Alleles will occur in pairs ex) HH, hh, Hh
Homozygous: having two of the same allele for one trait
ex) HH or hh
Heterozygous: Having two different alleles for a trait
ex) Hh

8. When the alleles of a trait are heterozygous, there will be a:
dominant allele (visible)
recessive allele (masked or hidden)
Law of Dominance: if a dominant allele is
present, that trait will be shown

9. http://learn.genetics.utah.edu/content/inheritance/traits/ (trait inheritance)
How are traits determined?
The mother and father will each have 2 alleles for a trait represented as a:
Genotype: the alleles for a particular trait (letter combination
ex) HH, Hh, hh)
because you only see one trait in a pair of alleles, this is
called the phenotype

10. Problem: A father has brown eyes, a mother has brown eyes, and
their new child has blue eyes?
Step 1: Create a key
trait eye colour : B = Brown (dominant)
b = blue (recessive)

11. What are the allele pairs of each parent?
father: either BB or Bb
mother: either BB or Bb
explain?

12. step 2: create a Punnett Square
Punnett Square: a diagram used to predict the probability
that an offspring will have a specific genotype
Possibility 1:
Father: BB
Mother: BB
results: 100% brown eyes
0% blue eyes
What are the possible genotypes and
phenotypes?

13. possibility 2:
Father: BB
Mother: Bb results: 100% brown eyes
0% blue eyes
What are the possible genotypes and
phenotypes?
possibility 3:
Father: Bb
Mother: Bb results: 75% brown eyes
25% blue eyes
What are the possible genotypes and
phenotypes?

14. Where did this come from?
https://www.youtube.com/watch?v=Mehz7tCxjSE

15. Dragon Genetics Activity
- must choose a partner
- partners must have 1 male
dragon and 1 female dragon