Genetics Vocabulary

What is genetics? It is the

study of how traits are passed on from parent to offspring.

Heredity: the passing of traits from parents to offspring(children)Our parents pass on to us the color of

our hair, eyes, height, etc. Sometimes you might have curly hair

even though both parents have straight hair. Why?

What is asexual reproduction?

Asexual Reproduction- when only one parent is needed.

Offspring is genetically identical (the same) as the parent.

Starfish Bacteria Spider Plant

What is sexual reproduction? The combination of two parent

cells to make an offspringWhen genetic material (male and

female)combine to make offspring

The joining of a sperm and egg to sexually reproduce offspring

Self-pollinating plant- has both male and female reproductive structuresPollen from one flower or plant can

fertilize the eggs of the same flower or the eggs of another flower of the same plant

It can pollinate another flower or itself

True-breeding plant: plant will always produce offspring with the same trait the parent plant has. Example: A true-breeding plant with

yellow flowers will always have offspring with yellow flowers.

What is a gene? Genes: segments of DNA on a

chromosome that control inherited traitsIt tells you your hair color, eye color

etc.

What is an allele? Alleles: a letter that is used to

represent a genetic trait Each gene is represented by two

alleles or two letters (one from each parent) Ex. Hair color- one allele from mother and

one from the fatherBrown hair is represented by a B and blond

hair is represented by a b.

Genotype: letter representation of a trait You cant see it! Ex. E – dark colored eyes e – blue eyes H – straight hair h – curly hair

Phenotype: What the trait looks like You can use your five senses to see it. Ex. You can see the color of your hair.

Dominant Trait: It is a gene/trait that always shows up. It always takes over. It is represented by a CAPITAL LETTER.

Examples: Brown eyes – B Freckles – F

Recessive Trait: A RECESSIVE trait is a gene/trait that is hidden when the dominant gene is present. It only shows up when it is by itself. It is represented by a lower case letter.

Examples: Blue eyes – b No freckles – f

What are Homozygous Alleles?

Homozygous means having the samesame allelesalleles for one gene.

Examples:Brown eyes – BBBlue eyes - bbFreckles – FFStraight hair - hh

What are Heterozygous Alleles? Heterozygous means having the differentdifferent

allelesalleles for one gene.

Examples:Brown eyes – BbFreckles - Ff

What is a punnet square? Punnett Square:It

is a genetic diagram that helps scientist to predict the chances of getting a certain trait.

What is probability? Probability: the mathematical

chance that an event will happenProbablility is used in genetics to see

the chance that a certain traits will occur. Ex. The probability that you were going to

be born a female was 50%