What did Mendel do to study different traits in his genetics experiments?
He cross-pollinated plants.
Factors that control traits are called
Scientists call an organism that has two different alleles for a trait
What does the notationTT mean to genetics?
Two dominant alleles
What does the notation Tt mean to geneticists?
One dominant allele and one recessive allele
What is probability?
A number that describes how likely it is that an event will occur
What does a Punnet square show?
All the possible outcomes of a genetic cross
An organisms physical appearance is its
What is the chromosome theory of inheritance?
Genes are carried from parents to offspring on chromosomes
What happens during meiosis?
Chromosome pairs separate and are distributed into new sex cells
When sex cells combine to produce offspring , each sex cell will contribute
Half the number of chromosomes in body cells
What determines the genetic code?
The order of nitrogen bases along a gene
The order of nitrogen bases along a gene determines the order in which
Amino acids are put together to form a protein
What does messenger RNA do during protein synthesis?
Copies the coded message from the DNA and carries it to the cytoplasm
What do transfer RNA molecules do during protein synthesis?
Carry amino acids and add them to the growing protein
What is a mutation?
Any change in a gene or chromosome
A mutation is harmful to an organism if it
Reduces the organism’s chances for survival and reproduction
Which term refers to physical characteristics that are studied in genetics?
The different forms of a gene are called
Where does protein synthesis take place?
On the ribosomes in the cytoplasm of a cell
An organisms genotype is its
Which nitrogen base in RNA is NOT part of DNA?
An organism that has two identical alleles for a trait is
A heterozygous organism has
Two different alleles for a trait
Chromosomes are made up of
Many genes joined together