Genetics

What is Meiosis?

Cell division in reproductive organs resulting in gametes.

What are Gametes?

Sex cells; in animals, sperm and egg; in flowering plants, pollen and egg.

What is a Clone?

Genetically identical organisms.

What is Variation?

Differences between organisms.

What is DNA?

A polymer made up of two strands forming a double helix.

What is a Chromosome?

A long strand of DNA wrapped around proteins that contains many different genes.

How many pairs of chromosomes do humans have?

Humans have 23 pairs of chromosomes.

What is a Gene?

A small section of DNA on a chromosome that codes for a protein.

What is a Genome?

All the genetic material (DNA) in an organism.

What is a Phenotype?

The physical characteristic/trait that an organism has.

What is a Genotype?

The two alleles an organism has for a particular characteristic.

What is an Allele?

A version of a gene.

What does Dominant mean in genetics?

An allele that is always expressed in the phenotype.

What does Recessive mean in genetics?

An allele that is expressed in the phenotype only if there is no dominant allele.

What does Homozygous mean?

When the alleles in the genotype are the same.

What does Heterozygous mean?

When the alleles in the genotype are different.

What is Polydactyly?

An inherited condition characterized by having extra fingers or toes, controlled by a dominant allele.

What is Cystic Fibrosis?

An inherited condition characterized by the production of thick sticky mucus, controlled by a recessive allele.

What are the types of reproduction?

Sexual (fusion of gametes) and Asexual (no fusion, genetically identical offspring).

How many daughter cells does Mitosis produce?

2 daughter cells.

How many daughter cells does Meiosis produce?

4 daughter cells.

What is the genetic material in the nucleus composed of?

A chemical called DNA.

What does RNA Polymerase do during transcription?

RNA Polymerase helps make a copy of DNA as mRNA.

What is the role of mRNA?

To carry the genetic information from the nucleus to the ribosomes where proteins are synthesized.

What is the triplet code?

A sequence of three bases on mRNA that codes for a specific amino acid.

What is a mutation?

A new form of genes resulting in changes in existing genes.

What is the purpose of embryonic screening?

To test for alleles and detect genetic disorders in embryos.

What is Amniocentesis?

A procedure to take a sample of amniotic fluid from the area surrounding the fetus to test for genetic disorders.

What is the ethical concern about embryo screening?

That parents may face dilemmas regarding terminating pregnancies based on genetic test results.

What is the dominant allele representation for having dimples?

D (D for dimples).

What is the recessive allele representation for not having dimples?

d (d for no dimples).