Genetics Flashcards
What is DNA?
How many chromosomes in the body?
46 chromosomes
How many homologous pairs in the body?
26 homologous pairs
Autosomes**
DEF:
22 pairs
Sex chromosomes***
DEF:
Female are XX
Males are XY
Karyotypes
is a photographic inventory of chromosomes
A photo that displays all chromosomes for one person
Haploid cells
Haploid cells contain only one set of Chromosomes (n).
Haploid cells are formed by the process of meiosis.
EX: gametes
23 chromosomes
Diploid Cells
Diploid cells contains two sets of chromosomes (2n).
Diploid cells undergo mitosis.
EX: include blood cells, skin cells and muscle cells.
46 chromosomes
Gametes*****
Sex cells (egg and sperm cells)
???An OO site for sperm???
Haploid cells
23 chromosomes each
**** HAPLOID/GAMETES
DIF?**
**Sexual reproduction leads to variation
Three major processes mean variation is the norm for
sexual reproduction:
- Independent assortment
- Random fertilization
- Crossing over
***Independent assortment
Chromosomes line up
by homologous pairs
during meiosis
I.
Maternal and paternal
chromosomes are
shuffled randomly.
***Random fertilization
Crossing over
Occurs when homologous chromosomes line up during meiosis I.
Crossing over creates new hybrid chromosomes, which increases gene variation.
Chromosomes can
“swap” genetic material,
creating new, unique
combinations.
Gregor Mendel
The first to deduce the basic principles of inheritance. (1822-1884)
