B2: Cell division/Specialisation Flashcards
What is mitosis?
Part of the cell cycle where one set of new chromosomes is pulled to each end of the cell forming 2 identical nuclei, during cell division.
What is the cell cycle?
the series of stages where body cells divide.
Why is mitotic cell division important in the cell cycle? (3)
- growth
- repair/replacement of worn cells
- development
of multicellular organisms
What is the difference in differentiation process between animal and plant cells? (2)
Animal cells differentiate at early stage
Plant cells retain the ability to differentiate throughout life
What happens when cells differentiate? (2)
- it gets different sub-cellular structures that enable it to carry out a particular function.
- cell specialise
what is the importance of differentiation in the development of a baby?(2)
- cells need to specialise to become part of body
- babies need different types of cells
- without differentiation cells won’t specialise so organs can’t develop
Explain the stages of the cell cycle and mitosis.
3) before dividing again, cells need to grow and increase ribosome/mitochondria numbers
4) DNA replicates to form 2 copies of each chromosome
5) one set of chromosomes is pulled to each end of the cell and cell divides
6) The cytoplasm/cell membranes also divide to form 2 identical daughter cells - cytokinesis
Where in the plant is mitosis constantly happening?
The meristems
What is a stem cell?
An undifferentiated cell that can form other types of cells/tissues.
What conditions could stem cells help to treat?
Paralysis Diabetes Transplant surgeries Infertility Dementia
What is meant by therapeutic cloning?
Where an embryo is produced with the same genes as the patient so the stem cells produced are not rejected/ may be used for treatment
Risks of using stem cells to treat conditions.
- can cause cancer
- stem cells could be infected with viruses and transfer infection
- low no. stem cell donors
Objections of using embryonic stem cells for treatment.
- embryo can’t give permission
- violation of human rights
- interrupts process of human reproduction
- destroys potential life
How does an embryonic stem cell differ from an adult stem cell? (3)
- Adult stem cells form many but not ALL types of cell
- Embryonic stem cells are found in embryos/early development
- Adult stem cells are present throughout an animal/human regardless of age
What is differentiation?
The process where cells become specialised for a particular function.