genetics

What is a genetic disorder?

an abnormal condition that a person inherits through genes on chromosomes

What is a dominant allele?

an allele that always shows in an organism

What does Rr mean?

heterzygous, hybrid, dominant

What is Cystic Fibrosis?

a genetic disorder where the body produces abnormally thick mucus in the lungs and intestines; making it hard to breathe and digest food.

What is a mutation?

A change in a gene on chromosome that cause genetic disorders.

What is Sickle-Cell Disease?

A genetic disorder caused by abnormal hemoglobin which causes people to suffer from lack of oxygen in the blood making them experience pain and weakness.

What is Down's Syndrome?

A genetic disorder due to an extra copy of chromosome 21

What is hemophilia?

A genetic disorder where the blood clots very slowly or not at all.

What did Gregor Mendel do to study different characteristics in his genetics experiments?

He cross-pollinated plants.

genotype

an organism's genetic make-up example:BB,Bb,bb

Scientists call an organism that has two different alleles for a trait

hybrid

An organism's physical appearance is it's?

Phenotype

What does the notation TT mean to geneticists?

Two dominant alleles

gene

factors that contol traits

Walter Sutton discovered that the sex cells of grasshoppers have

half the number of chromosomes found in the body cells

When sex cells combine to produce offspring, each sex cell contributes

half the number of chromosomes in body cells

purebred (homozygous)

having the same alleles for a trait example:BB or bb

What does it mean to be homozygous for a particular trait such as widow's peak?

having the same alleles for widow's peak Example: WW or ww

What does it mean to be heterozygous for tallness in pea plants?

having the two different alleles for tallness Example: Tt

hybrid (heterozygous)

having two different alleles for a trait example:Bb

What does RR mean?

homozygous, purebred, dominant Capital letters are dominant

What does rr mean?

homozygous, purebred, recessive Lower case are recessive

What is the chromosome theory of inheritance?

it states that genes are earned from parents to their offspring on chromosomes

How does probability relate to Punnett Squares?

it tells us the probability of genetic crosses

Where are genes located?

on the chromosomes

trait

phisical characteristics studied in genetics

allele

the different forms of a gene

Factors that control traits are called

Genes

What do we call the factors that control your traits?

Genes

What does the notation Tt mean to geneticists?

One dominant allele and one recessive allele

Why do geneticists use Punnett Squares?

They use it to show all of the possible outcomes of genetic crosses and the percentage of each.

What does a Punnett Suare show?

all the possible outcomes of genetic cross

What is a recessive allele?

an allele that is hidden when a dominant allele is present

phenotype

an organisms physical appearance example:tall,short

what is probability?

the chance of something occuring

what is heredity

the passing of traits from parents to offspring

What is meiosis?

the process by which the number of the chromosomes is reduced by half to for sex cells-sperm & eggs

what is a proportion?

the ratio between two numbers

what is genetics

the scientific study of heredity