Cell Division and Growth Flashcards
(Exam-style question)
A tumour can occur in any organ in the body. Not all tumours are cancerous.
Explain how a tumour forms.
- A mutation in one of the genes that controls cell division causes cells to divide uncontrollably
- This creates an abnormal mass of cells
Describe the point at which a tumour is classed as a cancer.
When the tumour invades and destroys surrounding tissue
List the 3 processes involved in growth.
- Cell division
- Cell differentiation
- Cell elongation
What are the processes involved in the growth of animals?
Cell division and differentiation
What is cell differentiation?
The process by which a cell changes to become specialised for its function
What are the processes involved in the growth of plants?
Cell division, elongation and differentiation
What is cell elongation?
Cell elongation makes a plant’s cells expand so the cells get bigger, making the plant grow
Where does growth that usually occurs by cell division happen in a plant?
The tips of the roots/shoots
(Exam-style question)
Describe two differences between the growth of animals and the growth of plants.
Any two from:
- Animals don’t grow by cell elongation, but growth in the height of a plant occurs by cell elongation
- Animals tend to grow while they’re young, and then they reach full growth and stop growing, while plants often grow continuously
- In most animals, cell differentiation is lost at an early stage but plants continue to differentiate to develop new parts throughout their lives
Describe how percentile charts are used to monitor growth.
- Used to establish an overall pattern in development, helping to highlight any problems
- Helps doctors know when to conduct investigations if there are any inconsistent patterns
- (e.g. the 50th percentile here shows the mass that 50% of babies will have reached at a certain age)
Give three measurements that could be plotted on a percentile chart to monitor growth.
- Length
- Mass
- Head circumference
