Heredity Vocab

chromosome

building block of heredity; contains genes and DNA; in nucleus

homologous chromosome

Same size and banding pattern chromosomes

centromere

attaches two chromatids together; binds in middle

diploid

Body cells are ….. because they have a complete set of 46 chromosomes

haploid

Sex cells are ….. because they have half the amount of chromosomes

gametes

sex cells (sperm and egg)

zygote

fertilized egg

mitosis

the process of creating body cells

meiosis

the process of creating sex cells (gametes)

karyotype

A photo of the chromosomes arranged by size

nondisjunction

When a cell receives too little or too many chromosomes

chromatids

one of the two identical DNA strands of the chromosomes

crossing over

Homologous chromosomes exchange genes

independent assortment

describes how different genes are inherited during reproduction

nucleotide

Made up of phosphates, deoxyribose sugar, and nitrogenous base

double-helix

“Twisted ladder” ; shape of DNA

anti-parallel

The ends of the DNA strands are opposite meaning…

semi-conservative

Each new DNA strand during replication contains one original and one new strand

transcription

coding region of DNA is converted to mRNA

translation

amino acids are joined together and folded into a protein

mRNA

messanger RNA; carries genetic information from DNA to ribosomes for protein synthesis.

amino acids

building blocks of proteins that link together during translation

codon

A sequence of three nucleotides in mRNA that corresponds to a specific amino acid or a stop signal during protein synthesis.

homozygous

Having two identical alleles for a trait.

heterozygous

Having two different alleles for a particular gene.

dominant

An allele that expresses its trait even when only one copy is present in the genotype.

recessive

An allele that is masked by a dominant allele in the phenotype of an organism.

allele

A variant form of a gene that can produce different traits in an organism.

gene

A segment of DNA that codes for a specific trait or function.

phenotype

The observable physical or biochemical characteristics of an organism, determined by its genotype.

genotype

The genetic constitution of an organism, determining its traits. It consists of the alleles inherited from the parents.