ch 6 & 7 mitosis n meiosis Flashcards
WHAT is genome
a cell’s entire DNA
What is the Prokaryotics Genome?
- no nucleus
- DNA is in area called nucleoid
- has plasmids little boops of DNA outside nucelois
What is the Eukaryotics Genome?
-DNA inside nucleus
- chromosomes,
- several dbl stranded and linear DNa
What makes up the Human Genome?
- somatic cells
- diploids
- gametes (haploids)
what are the somatic cells?
body cells, nOT INCLUDING SEX CELLS
- 46 chromos, 23 pairs
what is a Diploid?
Chromosome pair, referred to as 2n
What are Homogolous Chromosome Pairs
- matched and same chromosomal pairs
- called genes, and makes up who we are
What are the GENERAL MAjor phases of a Cell’s Cycle?
- Interphase
- Mitotic Phase
(remember IM)
What is the G1 phase in Interphase? explain
- G1 : gap one, cell gathers energy, nutrients to prepare itself for DNA replication
- nothing happens on outside, only inside
What is the S phase in Interphase>
Synthesis
- DNa replication
- sister chromatids are created which are two EXACT copies of chromosome dna
what are the Sister Chromatids (Mitosis) held tg by
Held together in the Centromere. the mama
What is the G2 phase
Gap two
- organelles are getting duplicated and now its ready for Mitotic phase
What happens generally to the cell in the Mitotic Phase?
the cell divides itself
- formation of daughter cells that are identical to one another
- diploid to diploid
What is PPMAT ?
Mitosis phases
- prophrase
- prometaphase
-metaphase
-anaphase
-telophase
What happens in Prophase
- nuclear envelope breaks down
- chromosomes condense and now visible
- spindle fibres emerge from centrosomes and go to oppo side of cell
what happens in Prometaphase
- chromos are very condensed atp
- kinetochores appear at centrosomes
What happens in Metaphase?
- sister chromatids line up at the middle of cells
- sisters attached to spindle fibres
Whjat happens in Anaphase>
Sister Chromatids get pulled apart to oppo sides of cell
What happens in Telophase
sister chromatids are now CHROMOSOMES
- and are at opposides of cells
- nucelar envelop begins to form around new chromos
What occurs during Cytokinesis?
When cell divides from cleavage thing and splits into TWO DAUGHTER CELLS
Which phase does a cell spend most time in?
Interphase
What is the Benefits of both Sexual and Asexual Reproduction?
Sexual: genetic variability
Asexual: no need for mate and faster
What are the different Life Cycles? explain them
Fertilization - plants do this and makes its own offspring
Diploid Dominant - multicelluar, has no haploid stages
Haploid Dominant = not multicelluar
Alterations of Generations - has haploid and diploid stgae
WHAT generally happens to cell during Meiosis
the cell goes from Diploid to Haploid Daughter cells
What are the rounds of Meiosis?
1 round of chromo duplication
2 rounds of cell dividision
Meio Interphase 1
- ismilar to mitosis
- has G1, S, G2
Meio Prophase 2 and important thing that occurs?
- nuclear envelope breaks down
- homo chromos are paired by cnetromere
- Crossing Over - between the non sister chromos
Meio Prometaphase 1
- spindle fibres attach to centromeres - called Tetrad Pair
- end of process the pairs connect to microtuble
Meio Metaphase 1
- Homo chromosomes line up down middle
-Independant Assortment happens at random between the pairs
Meio Anaphase 1
sisgter chromastids r bounded by centromere and get slowly pulled apart
Meio Teloplahse 1
chromosomes pairs at oppo sides of cell
-nuc envelop forms
Cytokinetis in Meisos
splits into two daughter cells and are haploid with 2 sister chromotids
- still considered haploid
Main things that occur in Meiosis 2
-remaining sister chromatids must divide again
- divide in four haploid daughter cells
how many celluar divisions occur in Mito and Meio
mito - 1
meio- 2
what stage has G1, S, G2
interphase
where does Crossing Over and Independent ASssrotment occur
Meiosis
Prophase and Metaphase
