genetics and heredity

Question 1

Genetics

Answer 1

is the study of heredity. Genetics involves studying how traits are passed from parents to offspring.

Question 2

Heredity

Answer 2

is the passing of traits from parents to offspring.

Question 3

Traits

Answer 3

are the characteristics of an organism. Examples are eye color, freckles, height or dimples.

Question 4

Chromosome

Answer 4

Chromosomes are thread-like structures in the nucleus of cells that carry genetic information. A chromosome consists of a long strand of DNA containing many genes.

Question 5

DNA

Answer 5

Deoxyribonucleic acid (DNA) is a molecule made up of nucleotides that contains genetic information for cell growth, division and function.

Question 6

Gene

Answer 6

• A gene is a segment on a chromosome that determines a specific trait. Genes are the units of heredity

Question 7

allele

Answer 7

a different form or version of a gene - alleles usually occur in pairs

Question 8

dominant

Answer 8

a gene variant that is expressed more strongly than other versions of the same gene - the dominant allele masks the effect of the recessive allele

Question 9

recessive

Answer 9

a gene that is masked by a dominant gene, and is only expressed when two copies of the gene are present

Question 10

genotype

Answer 10

the genetic make up or code of an organism - Ex: BB, Bb, bb

Question 11

phenotype

Answer 11

the observable traits or physical appearance of an organism - Ex: brown eyes or blue eyes

Question 12

homozygous

Answer 12

If an organism has two of the same kind of gene for a trait, it is called pure or homozygous.
Example: Homozygous brown eyes (BB) ~ Homozygous blue eyes (bb)

Question 13

heterozygous

Answer 13

An organism with two different alleles for a trait is called heterozygous or hybrid.
Example: A heterozygous tall plant (Tt) expresses the dominant allele (T or tall) and thus, is tall