2.1 Producing New Cells Flashcards
What is the 1st stage of mitosis?
The DNA in the cell replicates.
What is the 2nd stage of mitosis?
The DNA coils up into chromosomes. Each chromosome consists of two sister chromatids.
What is the 3rd stage of mitosis?
Spindle fibres line the chromosome up on the equator of the cell.
What is the 4th stage of mitosis?
Chromosomes split into two and spindle fibres pull the chromatids apart.
What is the 5th stage of mitosis?
A new nuclear membrane forms around the chromosome at each pole of the cell.
What is the 6th stage of mitosis?
Cytoplasm divides to make two cells.
What is meant by the term chromatid?
A chromatid is one of two identical halves of a replicated chromosome.
What is the centre of the cell called?
The equator
What are spindle fibres?
Spindle fibres are rope-like structures which attach themselves to the centromere of the sister chromatids. The spindle fibres line up the pairs of chromatids at the equator of the cell.
Why do we need mitosis?
For growth and repair of damaged tissues and replacement of damaged cells. It also maintains the diploid chromosome complement.
What are stem cells?
They are unspecialised cells which can divide in order to self-renew. They have the potential to become different types of cell. They are also used for growth and repair.
What are the two different types of stem cells?
Embryonic stem cells and Adult stem cells.
What is specialisation?
The specialisation of cells leads to the formation of a variety of cells, tissues, and organs.
What is the sequence of hierarchy?
Cells —> tissues —> organs —> systems.
What does the term diploid mean
A cell with two matching sets of chromosomes
