B1.2: Cell Division Flashcards
Define the term chromosome
(B1.2.1.1)
A chromosome is a structure formed by the coiling
of DNA helices in the nucleus of a cell
True or False.
Each chromosome carries a large number of genes
(B1.2.1.2)
True.
Each chromosome carries many genes which code for many different types of protein
How many chromosomes do human body cells contain?
(B1.2.1.3)
Human Body cells contain 23 pairs of chromosomes which totals to 46 chromosomes
Why are chromosomes found in pairs in human body cells?
(B1.2.1.4)
One chromosome in each pair is inherited from each parent
How is the chromosome number in the gametes different to that of body cells?
(B1.2.1.5)
Gametes (sperm and egg cells) contain the haploid number of chromosomes
i.e - half the number of chromosomes as human body cells
True or False.
Chromosomes are only visible during cell division
(B1.2.1.6)
True.
Chromosomes condense and become visible during cell division
Define the term mitosis
(B1.2.2.1)
Mitosis is nuclear division that results in the production of genetically identical cells
It is used for growth, repair, and asexual reproduction
True or False.
Mitosis results in genetically diverse cells.
(B1.2.2.2)
False.
Mitosis results in genetically identical cells
What happens to chromosomes before mitosis?
(B1.2.2.3)
Before mitosis, each chromosome replicates, producing two identical copies of each chromosome: one for each of the two daughter cells
Why is mitosis important in the body?
(B1.2.2.4)
Produce new cells for growth, repair of damaged tissues and the replacement of cells
What is the outcome of mitotic division?
(B1.2.2.5)
Two genetically identical daughter cells
What cells are not produced by mitosis in animals and plants?
(B1.2.2.6)
The gametes (sperm, egg cells, pollen and ovules)
They are produced by meiosis
True or False.
Mitosis is another name for the cell cycle
(B1.2.3.1)
False.
Mitosis is part of the cell cycle
Name the three stages of the cell cycle
(B1.2.3.2)
- Cell Growth — DNA replication and organelle replication
- Mitosis — Division of the nucleus
- Cytokinesis — Splitting of the cytoplasm
True or False.
Ribosome numbers increase in cells before mitosis occurs
(B1.2.3.3)
True.
The sub-cellular structures must replicate. This include ribosomes and other organelles such as mitochondria
Define the term Stem Cells
(B1.2.4.1)
A stem cell is an undifferentiated cell capable of making many more cells of the same type
- by allowing them to differentiate
True or False.
Embryonic stem cells can differentiate to produce most cell types
(B1.2.4.2)
True.
This enables them to form the tissues and organs needed during development
How can stem cells be used to treat diseases such as diabetes?
(B1.2.4.3)
By replacing damaged/unhealthy cells with healthy stem cells
*these can continually divide to form more healthy cells
What is the potential benefit of being able to use a patients own stem cells in medical treatment?
(B1.2.4.4)
Stem Cells from the same patient would not be rejected by the patients immune system
True or False.
There is a risk of infection when transferring lab-cultured stem cells into a patient
(B1.2.4.5)
True.
Stem cells cultured in a lab can become infected. Infection can then be passed to patients during therapy
True or False.
There is ethical issues associated with the use of embryonic stem cells in medicine
(B1.2.4.6)
True.
Such as:
• Destruction of embryos
• Embryos cannot give consent
• Embryos are treated as a commodity
True or False.
Adult stem cells have a limited capacity to differentiate
(B1.2.4.7)
True.
They can only make a certain few cell types
Name the tissue type found in plants where stem cells are located
(B1.2.4.8)
Stem Cells in plants are found in meristem tissue
*in the growing roots and shoots
Where in the human body do stem cells differentiate to form red blood cells?
(B1.2.4.9)
Bone Marrow
How can meristem cells be used, alongside cloning, to aid plant conservation and crop development?
(B1.2.4.10)
To quickly produce large numbers of endangered plant species
