bio chapter 6
Terms
undefined, object
copy deck
- chorionoc villi sampling
- where the doctor counts the chromosomes
- telophase
- chromosomes uncoil, new nuclear envolope forms, spindle fibers break down. MITOSIS IS COMPLETE!!!!!:)
- crossing over
- in the beginning of meiosis the pair of chromosomes are next to each other then exchange reciprical segments of dna.
- gene
- segment of DNA that transmits info from parent to offspring
- centromere
- The protein disk at The point where the two chromatids are atatched.
- microtubules extend which way?
- toward opposite poles of the cell.
- the two copis of each chromose are called________
- homologous chrommosomes
- duplication
- where the chromosome attaches to the homologues which carries 2 copies of that gene
- deletion
- when chromosomes break there is an absnce in the division and certain genes are lost
- metaphase
- chromosomes go to the center of the cell they are then held in place by the microtubles attached to the kineticore.
- prophase
- chromosomes begin to condense and become visible. Nuclear envelope begins to break down and the spindle fibers become visible.
- Trisomy
- when a diploid cell has an extra chromosome
- karyotope
- collection of chromosomes in an individuals cells.
- what is down syndrome technically?
- it is a trisomy of diploid number 21
- anaphase
- two chromatids seperate when the centromer splits. each cromatid is now a chromosome move toward opposite poles
- meiosis
- when the number of chromosomes is halved in cell division
- cytokenisis
- splits the two cells with a protein belt
- hapliod cell is differant from the diploid cell how?
- only one hmologue is found in each cell instead of two.
- diploid
- when a cell has 2 homologues of each chromosome
- in plants meiois often leads to_______
- spores, which lead to the production of gametes
- meiosis 1
- homologues seperate into 2 cells.
- how many homologues do you get from each parent?
- 1
- chromosome
- rod shaped structure that forms when a single DNA molecule and its offiliated particle are coild before cell division
- meiosis 2
- th2 2 cromatids in of each chromosome seperate into 2 haploid cells.
- how many chromosomes does the human cell have?
- 23 which make 46 chromatids
- explain kineticore
- when the chromosomes are condensing more microtubuals come from the centromere this area is called the kineticore and it is a platform that assemble the microtubuals.
- metaphase 1 meiosis
- homologues are moved bby spindle fibers to "the equator" of the cell.
- what determines a boy? a girl?
- presence of y, no presnece of y
- Meiosis 11
- chromosomes dont replicate but divede at the centromeres,(difference from mitosis**)
- Prophase 1 Meiosis
- homologues pair up and cross-over
- skipping replication
- because there is only one replication but 2 divisions in meiosis the number of chromosomes is halved.
- anaphase1 meiosis
- homologues seperate the chromosomes are pulles apart to the opposite poles. DIFF: the chromosomes don't seperate at the centromeres therefore nondisjuction can occur
- what causes trisomy?
- nondisjunction- 1 new cell recieves 2 chromosomes and the other recieves none:(
- chromatids
- form prior to cell division when the DNA molecule duplicates itself to insure that the 1st and 2nd are identical.
- telophase1
- chromosomes gather at the pole, cytoplasm splits them but now there are half as many chromosomes in the cell as in the original. giving this the name Reduction division
- translocation
- the fragment grabs a nonhomologuous chromosome
- sex chromosome
- the chromosome that determine one sex x or y
-
G1
S
G2
M
C -
cell growth
dna copied
growth and preperation
mitosis
cytokenesis - gametes refer to what?
- the use of egg cells for reproduction
- anaphase2
-
centromeres divide chromosomes move two opposite poles.
Meiosis 2 is followed by cytokenisis where the new enveloes form - binary fission
- a sexual reproduction that causes identicaloffspring
- crossing over can form what?
- genetic recombinations or making new combinations of the genes when they trade. then they dont have identical DNA anymore.
- summarize cell cycle.
- G1-> S->G2-> M-> C
- what happens during binary fission
- a bacterium makes a copy of its DNA and formd a new membrane and cell wll. then the cell splits into two
- The life of a eukaryotic cell is traditionally diagramed as what?
- cell cycle: a repeating sequence of growth an division through which many kinds of eukaryotic cells pass.
- cytokinesis
- when the cytoplasm divides
- haploid cells come together to form what?
- a diploid zygote or a fertilized egg
- what is DNA?
- a long molecule that controls functions and heredity. It coils tightly and duplicates to form chromosomes before cell division.
- the gsgmc is all the what?
- Interphase
- amneosentesis__
- amnioticwhere a doctor removes fluid from a pregnant woman to make a karyotype
- spindle fiber
- the cable that helps m,ove the chromosomes apart and is made of microtubuals in the g2 phase these are reassmbled
- true false, # of chromosomes in the cell is the same for all species
- FALSE!!!!
- mutations
- changes in the genetic material.
- inversion
- old fragment reatatches to the new one in an inverse orientation