Mod 5 IQ 2 Flashcards
What is mitosis
cell division resulting in daughter cells, with the same number and kind of chromosomes ad the parent
What is Interphase 1st stage
Interphase is the first step of mitosis
the cell prepares itself for the division
DNA replication occurs to produce two copies of each chromosome
What is prophase 2nd stage
Prohase is the second stage of mitosis
Duplicated chromosomes condense
the mitotic spindle forms at either end of the dividing cell
these spindles are composed of strands of microtubules which lengthen and shorten to pull chromatids
What is the prometaphase 3rd stage
Prometaphase is the stage between metaphase and prophase
The nuclear envelope breaks down
What is metaphase 4th stage
where pairs of condensed chromatids (sister chromosomes ) line up along the equator of the cell
What is anaphase 5th stage
sister chromatids are drawn to opposite poles of the dividing cell by the mitotic spindle
Microtubules bind to chromatids at the kinetochore and begin to shorten, separating pairs from each other
There is now only one copy of each chromosome at either end of the cell
What is telophase 6th stage
Two nuclear envelopes begin to form around the sperate sister chromatids
Cytokinesis also 6th stage
Two daughter envelopes separated by the tightening ring of proteins around the middle of the dividing parent cell - the nuclei are squeezed apart
Cytokeniss simultaneously to anaphase and telophase
Meiosis
cell division resulting in four daughter cells (gametes ) each with half the number of chromosomes of the parent cell
Interphase 1 (meiosis)
as with mitosis DNA replication occurs to produce two copies each chromosome
Prophase 1 (meiosis )
Chromosomes condense and he nuclear envelope breaks down (prometaphase)
Homologous chromosomes pair up, aligning next to each other along their full length (this is when segments of DNA at the same locus swap to create new gene combinations )
Metaphase 1 (meiosis)
homologous pairs (not individual chromosomes) line up along the equator of the separating cell
Anaphase 1 (meiosis)
homologous pairs are separated, pulled to opposite ends of the cell by the meiotic spindle
sister chromatids remain attached
Telophase 1 (meiosis )
Chromosomes arrive at opposite ends of the cell
two diploid daughter cells are formed by cytokinesis
Prophase 2
Chromosomes condense and the nuclear envelope breaks down
Metaphase 2
Chromosomes line up along the equator of the dividing cells
Anaphase 2
sister chromatids are separated by the spindle microtubules and pulled towards opposite sides
Telophase 2
Cytokeniss splits the dividing cell into two new cells
nuclear membrane form around each set of chromosomes
Four haploid daughter cells are formed, each containing half the number of chromosomes of the parent cell
What is Initiation in the process of DNA replication
Initiation (unzipping ) the enzyme helicase unwinds and separates complementary DNA strands by breaking the hydrogen bonds between nitrogenous bases
What is Elongation in the process of DNA replication
Elongation small pieces of RNA called primers that bind to the ends of the strands, signaling the starting point of replication DNA polymerase binds to separated DNA strand s at primer sites, and beginnings to add new base pairs which are complementary to the strand for example if the polymerase recognizes A, it will bind with a T
What is Termination in the process of DNA replication
DNA polymerase reaches the end of the DNA molecule, and two identical daughter strands now have been produced. Dtrands recoil into the double helix shape
How does DNA replication affect the continuity of species
by copying the genetic material of a cell replication ensures that information important for life is transferred down through the generations
DNA replication is a highly-fidelity process, ensuring that daughter DNA strands carry the same gene and encoding all the essential proteins for life
How does Mitosis affect the continuity of species
Mitosis increases the number of cells in an organism, allowing for the development of a multicellular body
Mitosis allows for old cells to be replaced ensuring that tissues continue to function effectively
mitosis allows us as humans to develop when we can pass on our genetic information onto offspring through sexual reproduction
mitosis creases the next generation of organisms
How does Meiosis affect the continuity of species
the combination of gametes from sexual reproduction creates new organisms that have inherited traits from both parents purposefully introduces variation. Processes of crossing over independent assortment and random segregation allow for combinations of different alleles
The genetic variation which is introduced my meiosis and sexual reproduction which is integral for the continuity of species as mutation and variation are essential factors for survival and evolution and evolution
