lecture #8 Flashcards
what are the roles of cell division
1) reproduction
2) growth and dev
3) tissue renewal and repair (skin cells, )
what is chromatin
DNA formation when cell is not dividing: long thin threads
what is a chromosome
DNA during cell division : chromatin tightly coiled around proteins (histones)
what do genes determine
characteristics: hair, flower color
where are genes located
on chromosome
what is DNA made of
nucleotides
what is a gene locus
specific place on chromosome where gene is located
what are the characteritics of genes
- occur on specific chromosome
- at a specific site on the chromosome
(like adress)
do all species have same amount of chromosomes
No
how many pairs of chromosomes do humans have
23 pairs (23 single chromosomes from mom, 23 from dad)
what is a karyotype
organised profile of a person‘s chromosomes, individuel‘s complet set of chromosomes
how are chromosomes arranged in karyotype
from largest to smallest (accept for sex chromosomes)
what is the genome
all the genetic materiel in the cell
what is an autosome? How many do we have?
a non-sex chromosome , 22 pairs
how many chromosomes do we have? How many of each type?
22 pairs of autosomes
1 pair of sex chromosomes
what can chromosomal alterations result in ?
genetic disorders
what is xx and xy
xx sex chromosomes = female
xy sex chromosomes = male
in what cells are autosomes (non reproductive chromosomes) found in
somatic cells (non sexual) and gametes (sex cells) , but in diff quantities
what are somatic cells
cells found in the body, non-gametic cells
what are gametes
egg cells and sperm cells
what are dipoid cells, what is the symbol
2N, meaning come in pairs, for humans, 46 chromosomes and 23 pairs
what type of cells are diploid cells
somatic cells
what are haploid cells, what is the symbol
N, do not come in pairs, for humans, 23 chromosomes,
what type of cells are haploid cells
gametes
