Chapter 13: Meiosis and Sexual Life Cycles Flashcards
Inheritance or heredity
One generation passes characteristic traits on to the next
Genetics
the study of heredity and variation
Genes (definition)
units of heredity encoded in DNA
Locus
Physical location of a gene on a chromosome
DNA is…
a polymer made of four nucleotides
What are nucleotides made of?
A base, a sugar, and a phosphate
What are the nucleotides?
A, T, G, C
Two DNA strands form a…
double helix
Genes (function)
Sequences of nucleotides that direct protein production
Diploid
Human somatic cells: 23 chromosome pairs
2n = 46 in humans
Haploid
Gametes: 23 chromosomes
n = 23 in humans
Karyotype
a display of homologous chromosome pairs
Homologous chromosomes
same genes/traits
Somatic cells
all chromosomes other than sex cells
Fertilization
Two haploid gametes form a diploid zygote