Unit 2 - KA1 Producing new cells Flashcards
What is a Chromosome?
Structures within the cell nucleus made up of DNA.
A section of a chromosome is called a gene.
What are diploid cells?
Contain two matching sets of chromosomes
What is mitosis?
The division of a cell to create two identical daughter cells
What is the first stage of mitosis?
Chromosomes condense, they shorten, thicken and become visible.
What is the second stage of mitosis?
Spindle fibres attach to the centromere
What is the third stage of mitosis?
Chromatids line up along the equator of the cell
What is the fourth stage of mitosis?
Spindle fibres contract and are pulled to opposite ends of the cell called ‘cell poles’
What is the fifth stage of mitosis?
The nuclear membrane reforms and two new nuclei are formed, both of which are genetically identical to the original parent cell
What is the sixth stage of mitosis?
The cytoplasm of the cell divides to produce two new daughter cells, they are genetically identical
Why is mitosis important?
It is involved in growth and repair of damaged tissues. It is involved in replacement of dead or damaged cells
What is a stem cell?
Unspecialised cell capable of dividing in order to self renew. They have the potential to become different cell types.
What is an embryonic stem cell?
They are obtained from an embryo at a very early stage of development. Stem cells taken from embryos have the potential to differentiate into all specialised cell types.
What is a tissue stem cell?
They can be found in body tissues throughout life. Stem cells taken from body tissues can only differentiate into the type of cells from where they have been extracted.
Advantage of stem cells
The use of stem cells can advance medical research helping scientists to discover for health conditions
Disadvantage of stem cells
May be destroying a potential human life by using embryonic stem cells in research
