T/F DNA can function in any form whether it is condensed in chromosomes or not.
False DNA cannot function in condensed form
______ are the vehicles that organize and carry the DNA from generation to generation by either the process of mitosis or meiosis
What is it called when Chromosomes are organized by their size?
T/F the number of Chromosomes in a species tells how complex a species is.
False, chromosome number does not have any significance
Set of protiens that attach to spindle fibers
Name the four ways a kinetochore can be positioned and explain
meta- middle, submeta- a lil above or below middle, acro-found on far end, telocentric- found at very end of pairs
2 haploid cells combined at conception produce a diploid _____
There are two major cell types that do not reproduce, what are they?
Heart and Nerve cells
Name and very generally describe the phases of the cell cycle
Interphase- cell growth through G1, S and G2 and M-Phase- nuclear and cell division through mitosis or meiosis
What happens to a cell with 4 chromosomes (2n=4) as it goes through the cell cycle (interphase and mitosis)? name number or chromosomes, DNA mol and Chromatids at each phase
- InterphaseG1- 4 chromosomes, 4 DNA mol, 4 chromatids
- S/G2- 4Chromosomes, 8 DNA mol, 8 chromatids
- M-phaseProphase- nuclear membrane disappears spindles form, 4 Chromosomes, 8DNA mol, 4 Chromatids
- Metaphase- 4 chrom, 8 DNA mol, 4 Chromatids
- Anaphase- 4+4 chromo, 8DNA, 0 Chromatids
- Telophase- 4+4 chromo, 4+4 DNA, 0 chromatids
- cytokinesis- 4 chromo, 4 DNA mol, 0 chromatids
Name and explain each Prophase I step of meiosis.
- Lepotene- chromosomes condense,
- Zygotene- condense + bivalents form w/synaptonemal complex to hold them together
- Pachytene- condense+ crossing over and recombination
- Diplotene- chiasmata hold bivalents together. Synaptonemal complex dissolves
- Diakinesis- nucelar membrane disolves and spindles attach to bivalents
When do bivalents come apart or reduce?
Anaphase I of meiosis
when do chromosomes come apart or reduce in meiosis?
what enzyme is responsible for seperating chromatids during cell division?
what happens to a cell with 4 chromosomes as it goes through meiosis and the cell cycle? explain number of chromosomes, DNA mol and chromatids
- Prophase I- 4 Chromo, 8 Chroma, 8 DNA mol, 2 bivalents
- MetaphaseI- 4 chromo, 8 chroma, 8 DNA mol, 2 Bivalnets
- Anaphse I- 2+2 Chromo, 4+4 chroma, 8 DNA, 2 Bivalents
- TelophaseI- 2+2 chromo, 4+4 chroma, 8 DNA, 2 bivalents
- Metaphase II- same
- Anaphase II- 2+2 Chromo, 0Chroma, 4+4 DNA, 0Bivalent