Carla - Introduction to the Cell Cycle Flashcards
What does the length of a cells life depend on?
The type of cell they are e.g. epithelia live for a short amount of time
How long do rbcs live for?
120 days
What is cell division?
The process by which new cells are made
What is mitosis?
Cell replication leading to division
Identical clones
Give three reasons why cells divide
Growth
Replace old cells
Replenish low numbers
What occurs when growth happens by accident?
Tumours are formed
What happens as cells age?
(3)
They get worn out
They become not as good at carrying out their function
Accidental mutations can occur
When might cells have to be replaced?
(2)
If cells have burst
If cells are damaged
What is required for cell division?
Cell signalling -> it is a very carefully regulated event
What must first be done before replication?
(4)
All the components required to make a new cell must be made
Genetic material must be copied
Identical copy of each chromosome must be made
All cell components
Explain how cell replication and division happens
(9)
Strands of DNA become more tightly packed into a condensed form
The parent and copy remain attached to each other in the one place
The membrane around the nucleus then breaks down
The chromosomes line up across the centre of the cell
The parent and copy then separate
The individual chromosomes move to opposite sides of the cell
The cell membrane begins to pinch inwards
Genetic information is enclosed in new nuclear membranes in parent and daughter
The chromosomes uncoil and turn into long threads of DNA again
How many phases are there to cell replication?
Two main phases
- interphase
- mitotic phase (M phase)
What happens in interphase?
The cell grows and makes a copy of its DNA
What happens in the mitotic phase?
The cell separates its duplicated DNA into two sets and divides its cytoplasm forming two new cells
How many stages are there to mitosis?
Five
