exam 4 mod 8 Flashcards
meiosis
nuclear division that produces cells that develop into gametes
when you have a diploid mother cell (2N) , how many daughter cells will be produced in meiosis?
4 haploid daughter cells (1N), different from the mother
meiosis, like mitosis, occurs at the end of the S (replication) phase of the cell cycle, so they have to
1) divide pairs of chromosome types
2) divide sister chromatids
chromosomes vs chromatid
Chromatid: one of two identical of a chromosome that from when the DNA replicated before cell division, connected at the centromere
Chromosome: structure with DNA that carries genetic info; made up of two identical strands, chromatid
meiosis I
division of homologous pairs of chromosomes
prophase I
chromosome condense, homologues PAIR and form synaptonemal complex, during pairing crossing over and exchanging genetic material between the homologous chromosomes
metaphase I
each pair of homologues line up at the equator and orientate in pairs randomly
anaphase I
chromosomes, each with 2 chromatids, move to opposite poles
telophase I
2 new daughter cells will contain 2 chromosomes each
meiosis II
division of sister chromatids
metaphase II
individual chromosomes line up at the metaphase plate
anaphase II
centromeres split, and chromatids separate to opposite poles
telophase II
each daughter cell contains one chromosome of each type
recombination
during meiosis I chromatids from homologous pairs can exchange strands
genetic parents
individuals contributing the 2 haploid copies of the genome that make up the offspring’s diploid genome
gestational parent
the individual that carries the development fetus in their uterus
social parents
individuals that take responsibility to raise offspring
if a geneticist were to closely examine the make-up of a single autosomal chromosome from one of your cells, that chromosome would be found to be…
a mosaic of gene derived from just 2 of your grandparents, either maternal or paternal grandparents
meiosis results in the formation of 2 types of
gametes in equal numbers
fertilization
restores the 2 copies of the gene to the offspring
monohybrid crosses and law of segregation
the offspring genotype is the specific allele that that they carry
phenotype
what we look like
the particulate theory of inheritance (PTI)
-characteristics are distinct and hereditary determinants (genes) are particulate in nature
PTI: each adult has 2 genes for each character…
different forms of the genes, alleles
PTI member of the gene pair segregate equally into
gametes
fusion of the gametes at fertilization
-restores the pair of genes and is random
-different genes assort independently in gametes
gene
basic unit of biological information, specific segment of the DNA that encodes a protein
allele
alternative forms of a gene
phenotype
observable characteristics
genotype
alleles at a locus
homozygote
identical alleles at a locus
heterozygote
different alleles at a locus
