Cell Division Flashcards
What do chromosomes do?
They carry genetic information in a molecule called DNA
When a cell divides, what does mitosis ensure about the cell genetic information?
That the genetic information is the same
Where is DNA?
In cells nucleus within chromosomes
What is a gene?
The code for the production of a protein within each section of a chromosome
How many chromosomes are in the human body and how are they arranged?
There are 46 chromosomes arranged into 23 pairs
What are the genes like in each of the 23 pairs of the human body cell?
They have the same types of genes
The 23rd pair of chromosomes in the human body cell are what chromosomes
Sex chromosomes
What are the chromosomes like within females?
They are identical in shape
What are female chromosomes often referred to as?
XX
What are the chromosomes like in a man?
They are different in shape there is an X and Y chromosome
What are the chromosomes referred to in a man?
XY
Describe the structure of a DNA
It is a polymer made up of molymers called ACGT
What does ACGT stand for
Adenine, cytosine. Guanine and thymine
What are the stages of the cell cycle?
Cell growth DNA synthesis further growth mitosis the cytoplasm separates and a temporary cell resting period
When do cells divide?
When an organism grows or an organism is damaged and needs to produce new cells
What happens in DNA synthesis?
The single strand of DNA that makes up chromosome produces an exact copy of itself
What happens to the nuclear membrane during mitosis?
It breaks down
What happens to the chromosomes at the end of mitosis?
They are pulled to each end of the cell
What cell structures divide in mitosis?
Nucleus, cytoplasm and cell membrane
What is formed at the end of mitosis?
Two identical daughter cells
How do you calculate the length of time in phase?
Observed numbers of cells of that stage over total number of cells observed times by total length of time of cell cycle
What are the six stages of the cell cycle?
Interphase prophase metaphase anaphase telophase cytokinesis
What happens during interphase?
The DNA copies itself and the cell enlarges and is checked for errors
What happens in prophase?
The cell prepares itself by condensing DNA into chromosomes and it breaks down the nucleus
What is metaphase?
Chromosomes line up across the middle of the cell