Biology: Genetics 2

Somatic Cells

diploid body cells (skin cells, muscle cells, etc.)

germ line cells

Diploid cells that undergo meiosis to form haploid gametes

Gametes

sex cells

Chromosome

threadlike structure within the nucleus that contains genetic
information that is passed on from one generation to the next

Homologous Chromosomes

term used to refer to chromosomes in which one
set comes from the male parent and one set comes from the female parent

Sister Chromatids

one of two identical "sister" parts of a duplicated chromosome

Autosome

chromosome that is not a sex chromosome; also called autosomal
chromosome

Sex chromosome

one of two chromosomes that determines an individual's
sex

sexual reproduction

type of reproduction in which cells from two parents unite
to form the first cell of a new organism

asexual reproduction

process of reproduction involving a single parent that
results in offspring that are genetically identical to the parent

Fertilization

process in sexual reproduction in which male and female reproductive cells join to form a new cell

Linked genes

genes that are typically inherited together because they are
located close to each other on the same chromosome

Diploid

term used to refer to a cell that contains two sets of homologous
chromosomes

Haploid

term used to refer to a cell that contains only a single set of genes

Meiosis

process in which the number of chromosomes per cell is cut in half
through the separation of homologous chromosomes in a diploid cell

Mitosis

part of eukaryotic cell division during which the cell nucleus divides

Zygote

a fertilized egg

independent assortment

one of Mendel's principles that states that genes
for different traits can segregate independently during the formation of gametes

crossing over

process in which homologous chromosomes exchange portions of their chromatids during meiosis

Nondisjunction

error in meiosis in which the homologous chromosomes fail
to separate properly

locus

location of where a gene is located on a chromosome

gene

sequence of DNA that codes for a protein and thus determines a trait;
factor that is passed from parent to offspring

Allele

one of a number of different forms of a gen

when does crossing over take place

prophase 1

when does independent assortment take place

metaphase 1

what is Mendel famous for

he learned that traits are passed from parent to child

Homozygous dominant

2 dominant alleles ex HH

Heterozygous

one dominant and one recessive allele ex Hh

Homozygous recessive

2 recessive alleles

sex linked traits

traits located on sex chromosmes

codominance

2 alleles are expressed separately ex spotted animal

incomplete dominance

2 alleles are expressed together, a blend of the 2 alleles

pedigrees

A way to model the inheritance of a specific trait through a family to track a specific disorder or identify an pattern of inheritance.

what is the phenotype of this child? B = brown eyes b = blue eyes

brown eyed boy

what is true about this child

girl who is a hemophilia carrier

why CANT men be hemophilia carriers

because they only have 1 x chromosome