Download Genetics vocabulary

Genetics
vocabulary
. Traits are determined by the genes on the
chromosomes. A gene is a segment of DNA
that determines a trait.
What is a chromosome?
• Found in the nucleus
• Contains the
genetic
information- DNA
• 23 chromosomes
come
From the father and
23 from the mother
What is a gene?
•
•
•
•
•
Piece of DNA found
On a chromosome
That determines
The inheritance of
A particular trait
Review----What is a trait?
•
•
•
•
•
•
Inherited from our parents
To offspring (children)
Examples:
Eye color
Hair color
Tongue rolling
What is an allele?
• Two different forms of a trait that a gene may have
• Usually
indicated by
An upper case
Letter and
A lower case
letter
T or t
I know what you are
thinking now!!
• If one chromosome comes from the mother and
one from the father, how can we use only 1 letter
for each trait (allele)?
• Glad you asked!!!
Genes are labeled using 2
letters. They are either:
• Heterozygous or
Hybrid
• An organism with 2
different alleles for a
trait
• Tt or Gg
• Homozygous
• An organism with 2
alleles that are the
same
• TT or tt
Is there a difference
between what the genes
say and what you see?
• Yes, what is that difference?
• Genotype- the set of genes carried by an organism
•
Examples are TT , GG, Tt, gg, Gg, tt
• Phenotype- what the organism looks like
•
Examples are Green, Tall, Short, Wrinkled
I bet that you are dying to know
why some letters are capitalized
and some are not ?
There are 2 types of traits
• Dominant
• A trait that “covers
up” the other form of
the
trait. This is the trait that
you see.
Indicated by using
CAPITAL LETTERS
T or G
• Recessive
• A trait that is covered up
by the dominant trait.
You would only see this
trait if both parents have
the same allele
• Indicated by using lower
case letters.
• tt or gg
So far, we have looked at
traits such as eye and hair
color?
• How can genetics (the study of heredity) be used
to improve lives?
In what ways can be genetics be used that is
negative to society?
What are ethics?
How can we predict the results of
Mendelian genetics?
• We can use a tool called the
• PUNNET T SQUARE.