B2 Cell division Flashcards
Why does the body need to produce new cells?
Growth, development and repair
What is the process in which new cells are produced?
Cell cycle
What does a parent cell divide to produce?
Two daughter cells
How many chromosomes do human body cells contain?
46
What are cells with pairs of chromosomes called?
Diploid
What are chromosomes with only one copy of each chromosome called?
Haploid
What are the three stages of the cell cycle?
Interphase, mitosis and cytokinesis
What is the longest stage of the cell cycle?
Interphase
What happens during interphase?
The cell grows and prepares for cell division and DNA is replicated and condense to become visible under a microscope
What happens during mitosis?
Cell fibres attach to chromosomes to opposite poles and the chromosomes are pulled apart - the nucleus reforms around each set
What happens during cytokinesis?
The cytoplasm and the cell membrane divide to form two identical daughter cells
What is growth?
When an organism gets bigger and is measured as the increase in its size, mass and length?
What is cell elongation?
In plants - cells get longer
What happens when cell mass increases?
Subcellular structures duplicate
Where does cell division take place?
All tissues in the body
What are stem cells?
Cells that have the ability to differentiate into different types of cell
When does cell mass increase?
During protein synthesis
When do cells become specialised?
Very early in development, around day 5-7 in a human embryo
What is meant by ‘differentiated cell?’
Stem cells that have become specialised, e.g. red blood cell
Where does cell division take place in plant cells?
Meristems/ meristematic tissue
Where are meristems found?
Tip of their roots and shoots
What happens once meristems have divided?
They elongate
