exam 4? stuff Flashcards
in bacteria and archaea summary
1) cellular machines make a copy of the singular chromosome
2) the original cell divides into two
-basically they clone themselves
mitosis is the process responsible for
distributing a copy of each chromosome to each daughter cell
M phase in the cell cycle
when mitosis and cell division occur
interphase
when growth and DNA replication occur
5-step sequence of mitosis
1) DNA replication during interphase
2) mitosis starts and the replicated chromosomes condense and the nuclear envelop breaks apart
3) the replicated chromosomes are moved to the middle of the cell
4) the sister chromatids in the replicated chromosome are pulled apart to opposite ends of the cell
4) cell division splits into two daughter cells with IDENTICAL chromosomes
prophase
1st phase of mitosis when the replicated chromosomes condense and the nuclear envelope breaks down
metaphase
middle of mitosis when replicated chromosome moves to the middle of cell
anaphase and telophase
when sister chromatids separate and each chromosome goes to opposite ends of cell and new cells form after division
germ cells
cells that directly give rise to sperm or egg cells which undergo MEOSIS
somatic cells
-undergoes MITOSIS
-cells that form the body
meiosis is 2 divisions; cells undergo DNA replication….
-prior to meiosis
-so the process starts with DIPLOID cells that have replicated chromosomes
where does the replication ploidy occur
meiosis I
the daughter cells of meiosis I are
haploid (each one has one chromosome from each homologous pair)
after each round of meiosis (so I and II) how many daughter cells in total are produced by a single parent cell, which was diploid and replicated chromosome
4
two important things about meiosis
1) reduces ploidy (cuts chromosome # in half) and restores ploidy in offspring
2) generated genetic variation
meiosis
-eukaryotic process that one of each homologous chromosome pair to daughter cells, resulting in half the chromosome number
gamete
cells that fuse to form a zygote; sperm and eggs cells
zygote
fertilized egg
crossing and recombination
-exchange of DNA strands btw non-sister chromatids during meiosis I
independent assortment
observation of the parental homologs line up at random before separating at the end of meiosis I producing an array of combinations in daughter cells
reproduce asexually
using mitosis to produce genetically identical clones of themselves
reproduce sexually
use meiosis to produce gamete that combine and result in genetically unique offspring
gametes are single ____ cells that combine to form ____ offspring
-haploid
-diploid
testes in males
where meiosis occurs and the haploid products begin to mature into sperm cells
epididymis
highly coiled tube where sperm complete their maturation and are stored
vas deferens
tube that carries sperm away from epididymis
seminal vesicle and prostate gland
secrete accessory fluids that mix with sperm at the end of the vas deferens
urethra
tube that functions as both the outlet for the urine to the bladder and the reproductive system mixture of fluids
ovaries
are the site of meiosis and early egg development
oviducts or fallopian tubes
the tubes that transport mature eggs away from the ovaries and are where fertilization takes place
uterus
a muscular sac where the early development of embryo occurs
cervix
is an opening at the bottom of the uterus where an offspring passes during childbirth
vagina
muscular tube that an offspring passes through during child birth and is used during sexual reproduction
