2 - Cells and Control - Mitosis & Stem Cells Flashcards
What is Mitosis?
Cell division resulting in two identical cells
What are the stages of Mitosis?
Pro
Meta
Ana
Tell
Cytokinesis
What is Prophase?
Chromosomes condense & membrane around nucleus breaks down
What happens in Metaphase?
Chromosomes line up at centre of cell
What happens in Anaphase?
Spindle fibres pull chromosomes apart - then move to opposite ends of the cell
What happens in Telophase?
Membranes form around the chromosomes, becoming the nuclei of the two new cells
(nucleus divided)
What happens in Cytokinesis?
Before telophase ends, cytoplasm and cell membrane divide - forms two separate cells
Why is Mitosis important?
For the development & growth of our body & embryos
What does Mitosis produce?
Two cells genetically the same as the parent cell
How is Cancer caused?
Uncontrolled cell division - can result in a mass of abnormal cells/a tumour
If tumour invades & destroys surrounding tissue it’s cancer
Describe growth in organisms in animals
- All growth happens through cell division
- Cells divide at fast rate when young - once you’re an adult cell division is for repair
- Most cell differentiation lost at an early stage
Describe growth in organisms in plants
- Growth in height mainly due to cell elongation
- Cell division usually happens in tips of roots/shoots
- Grow continuously - continue to differentiate to develop new parts (eg leaves, roots)
Why is cell differentiation important?
Allows cells to become specialised - allows multicellular organisms to work more efficiently
What are percentile charts?
Used to monitor growth so patterns in development can be seen & problems are highlighted (eg obesity, dwarfism)
What is the function of an embryonic stem cell?
To divide and produce any kind of cell at all
