All Cells Arise From Other Cells Flashcards
Within multicellular organisms do all cells retain the ability to divide
No
How many pairs of chromosomes do humans have
23 
At what stage of the cell cycle does DNA replication occur
Interphase 
Mitosis is a part of the cell cycle in which a eukaryotic cell divides to produce… containing
Two daughter cells
Identical copies of DNA
What is the point where the sister chromatids joined called
Centromere
What are the two stages of the cell cycle
Interfase and mitosis
What are the subcategories of interphase
G1. S. G2.
What happens in G1
Cell grows a new organelles and proteins made
What happens in S
Cell replicates its DNA, ready to divide by mitosis
What happens in G2
Cell keeps growing and proteins needed for cell division are made
Labelled chromrosome
Centromere (dot in the middle)
Chromatid ( 1 side)
Sister chromatids (the strands on either side)
What happens in Prophase
The chromosomes condense and become visible
Nuclear envelope breaks down and the chromosomes are free
What happens during metaphase
The chromosomes lineup along the equator
spindle fibres attach the centromere
What happens during anaphase
The centromeres splits separating into A pair of sister chromatids
The spindle fibres contract pulling chromosomes to opposite poles ( chromosomes are in a v shape)
What happens during telophase
Chromatids become chromosomes
Nuclear envelope forms around each group of chromosomes

What is cytokinesis
The division of the cytoplasm at the end of telophase 
What can happen during uncontrolled mitosis
Uncontrolled cell division can lead to a tumour and therefore cancer
Where are most cancer treatments directed
Controlling the rate of cell division
What is the proteome of a cell
The number of different proteins a cell is able to produce
Describe binary fission of bacteria
Replication of DNA
Replication of plasmids
Division of cytoplasm to produce two daughter cells
Why would the percentage of cell under going mitosis decrease as the organism gets older
Cells lose the ability to divide
Picture of chromosomes that are still connected and visible
Give two pieces of evidence that this cell was undergoing mitosis
The chromosomes are visible because they have condensed ( this is only 1 point not two)
Each chromosomes is made up of two chromatids because DNA has replicated
When preparing the cells for observation the scientist placed them in a solution that had a slightly higher (less negative) water potential than the cytoplasm. This did not cause the cells to burst but moved the chromosomes further apart in order to reduce the overlapping of the chromosomes when observed with an optical microscope.
Suggest how this procedure moved the chromosomes apart. X2
Water moves into the cells by osmosis
Cells get bigger
Suggest a way that chromosomes differ along their length. That when dyed different areas are darker or lighter
Different genes
Different base sequence
Difference in histones
What in picture shows that the cell was in anaphase
Chromatids are in two groups one each either polve
V-shaped SHOWED THAT THEY HAVE BEEN PULLED AT THEIR CENTROMERES
When does non-disjunction occur
Meiosis
