Chromosomes And Mitosis Flashcards
Most cells in your body have a nucleus what does the nucleus contain?
Genetic material in the form of chromosomes
What are chromosomes
Coiled up lengths of DNA molecules
Each chromosomes carries a large number of genes what do the different genes control?
The development of different characteristics eg:hair colour,eye colour
How many copies of each chromosome do body cells normally have
2 one from the organism mother and one from its father
How many pairs of chromosomes are in a human cell
23
What does the cell cycle make new cells for?
Growth,Development and Repair
What do body cells in multicellular organisms do to produce new cells (as a part of a series of stages called the cell cycle)
Divide
What is the stage of the cell cycle when the cell divides called
Mitosis
What do multicellular organisms use to grow or replace cells that have been damaged
Mitosis
What happens at the end of the cell cycle
Two new cells are produced that are identical to the original cell with the same number of chromosomes
In a cell that’s not dividing what is the DNA spread out into
Long strings
What does the cell have to do before it divides
The cell has to grow and increase the amount of sub-cellular such as mitochondria and ribosomes
After the cell divides it duplicates it’s DNA so there’s one copy for each new cell the DNA is copied and forms what shaped chromosome?
X-Shaped. Each arm of the chromosome is an exact duplicate of the other.
When is the cell ready for mitosis
Once it’s contents and DNA has been copied
What’s the first step of mitosis
The chromosomes line up at the centre of the cell and cell fibres pull them apart. The two arms of each chromosome go to opposite ends of the cell.
