2.4, 2.5 and 2.6 - Growth, Differentiation and Cancer Flashcards
How does growth occur in animals?
Growth in animals occurs via cell division and differentiation.
What process is involved in cell division in animals?
Cell division occurs by mitosis.
What happens after mitosis in animal cells?
After mitosis, cells can differentiate into specialised forms adapted to their function.
What is an example of specialised cells in animals?
Cells of the muscular system can bring about movement, and cells of the circulatory system are specialised to transport substances.
When do most animal cells lose their ability to differentiate?
Almost all cells differentiate at an early stage and then lose this ability.
How do specialised cells in animals reproduce?
Most specialised cells can make more of the same cell by undergoing mitosis.
What happens to red blood cells in terms of division?
Red blood cells lose their nucleus and cannot divide; they are replaced by adult stem cells.
What is the primary reason for cell division in mature animals?
In mature animals, cell division mostly happens to repair or replace damaged cells.
How does growth occur in plants?
Growth in plants occurs by cell division and differentiation, and also by a process called elongation.
What is elongation in plant growth?
Elongation is when plant cells grow longer in a specific direction by absorbing water into their vacuoles.
What controls the elongation process in plants?
Elongation is controlled by substances called auxins.
Do plant cells retain the ability to differentiate throughout life?
Many types of plant cells retain the ability to differentiate throughout life.
When do plant cells differentiate?
Plant cells differentiate when they reach their final position in the plant.
What is cancer in terms of cell division?
Cancer occurs as a result of small changes in cells that lead to uncontrolled cell division.
What is a tumour?
The group of cells that results from uncontrolled cell division is called a tumour.
