Genetics
What is genetics?
The study of heredity.
What is heredity?
The passage of genetic instructions (traits) from parent to offspring.
Sexual reproduction produces offspring that are genetically _____________ to the parents.
Similar but still different
Some genes can be hidden or covered up by another. These are considered to be-
Recessive
How are traits passed from parent to offspring?
Through genes during reproduction
Where is DNA located?
In the nucleus of your cells
When the environment determines which organisms survive and reproduce it is called?
Natural Selection
Asexual reproduction produces offspring that are genetically ____________ to the parent.
Identical
What is the punnet square used for?
To determine the outcome of genetic crossings.
Myotonic or fainting goats are goats that stiffen up and fall over when frightened, why would these goats still exist today?
Humans have artificially selected them for other traits.
What are the large threadlike structures of DNA that carry genes called?
Chromosomes
One way in which new variations may show up in a species:
Mutations
If you are studying a population of genetically identical individuals, you can conclude that these individuals reproduce how?
Asexually
A black chicken (BB) is crossed with a black chicken (BB). What percentage of offspring will be black?
100%
Why does a Punnet Square use capital and lowercase letters?
Capital = Dominant Trait Lower Case = Recessive Trait
Inherited traits that children get from their parents come from-
Genes
The physical trait observed in an offspring is known as it's -
Phenotype
For some traits, only one copy of a particular gene is needed to show a given trait. These genes are referred to as-
Dominant
Having dimples is dominant (D). Not having dimples is recessive. (d) Both parents are heterozygous for the dominant trait. What percentage of the children will NOT have dimples?
25%
How many parents are involved in asexual reproduction?
One
What do we call the genetic make up of the individual, represented by a set of letters?
Genotype
How many chromomsomes do humans have?
46 or 23 pair
Name two benefits of asexual reproduction compared to sexual reproduction:
It is fast
Do not need to find a mate
Long ears are dominant (E) in rabbits. If one parent is homozygous dominant for the long ear trait and the other homozygours reccessive (e), what is the only possible genotype of the offspring?
Ee
Two dark brown rabbits have four offspring. Three of the offspring are dark and one is white. What does this tell you about the parents' genes for fur color?
Dark brown is dominant and white fur is recessive. Both parents are heterozygous.