Cell Division Flashcards
What are the primary purposes of cell division?
Growth, replacement of cells, repair of damaged tissue
New cells carry the same genetic information to perform the same jobs.
What is contained within a cell’s nucleus?
Chromosomes
Chromosomes house genes, which have the instructions for making new cells and tissues.
What is a gene?
A section of DNA that controls a characteristic of the body
Genes are grouped together in chromosomes.
How many chromosomes do humans have in their body cells?
46 chromosomes in 23 pairs
One chromosome in each pair is inherited from the father and one from the mother.
How many chromosomes do sex cells (gametes) contain?
23 chromosomes
Sex cells have only one chromosome from each pair.
What is the cell cycle?
A series of stages that body cells go through to divide
It includes mitosis to produce identical cells.
What does mitosis produce?
Two identical cells with the same chromosomes and genetic information
It is essential for growth, development, and replacement of damaged cells.
What happens during asexual reproduction?
Offspring cells are produced by mitosis from parent cells
Offspring contain exactly the same genes as their parent.
What are the three main stages of the cell cycle?
- Cell growth and DNA replication 2. Mitosis 3. Cytoplasm and cell membrane division
Each stage is crucial for producing identical daughter cells.
What occurs in stage one of the cell cycle?
Cells grow, replicate DNA, and increase subcellular structures
This prepares the cell for division.
What happens during mitosis?
One set of chromosomes is pulled to each end of the cell and the nucleus divides
This is stage two of the cell cycle.
What occurs in stage three of the cell cycle?
The cytoplasm and cell membranes divide to form two identical daughter cells
This completes the cell division process.
What is differentiation in the context of cells?
The process by which unspecialised cells become specialised to perform specific functions.
What type of cells are unspecialised and can become any type of cell?
Stem cells.
How do specialised animal cells typically divide?
By mitosis, forming the same type of cell.
What happens to specialised cells that cannot divide?
They are replaced by adult stem cells.
Which type of cells cannot be replaced in adults?
Nerve cells.
In mature animals, what is the primary reason for cell division?
Repair and replacement of damaged cells.
What are meristems in plants?
Active regions in stems and roots where undifferentiated cells are formed.
How do plant cells differ from animal cells in terms of differentiation?
Plant cells can continue to differentiate throughout their lives.
What is cloning in the context of plants?
Producing identical offspring from a tiny piece of lead tissue.
What happens to plant cells during cloning?
They become unspecialised and undergo mitosis before differentiating into needed tissues.
Why is cloning animals more difficult than cloning plants?
Animal cells differentiate permanently early in embryo development.
Fill in the blank: In plants, differentiation is not _______.
permanent.
True or False: Animal cells can change back after differentiation.
False.
What process allows plant cells to grow and elongate before differentiating?
Mitosis.
What is the outcome of mitosis in specialised cells?
Formation of more of the same type of cell.
In what part of a plant do cells differentiate into specific cell types?
Their final position in the plant.
What is the primary role of adult stem cells?
To replace dead or damaged cells.
Fill in the blank: Cloning in animals mainly involves cloning _______.
embryos.
What are stem cells?
Undifferentiated cells that can develop into specialized cells
What forms when an egg and sperm cell combine?
A zygote
What do embryonic stem cells differentiate into?
All of the specialized cells of the body
Where are adult stem cells commonly found?
Bone marrow
What do stem cells do when tissues are injured or affected by disease?
They divide to replace the different types of damaged cell
True or False: Many differentiated cells can divide to replace themselves.
True
What is one condition that could benefit from stem cell therapy?
Paralysis
What do scientists hope embryonic stem cells can be encouraged to grow into?
Almost any different type of cell needed in the body
What type of studies have been conducted to check the safety of transplanting embryonic stem cells?
Small studies
What hormone do scientists aim to produce using stem cells to help treat diabetes?
Insulin
Fill in the blank: Stem cells from plant _______ are used to make clones of the mature parent plant.
meristems
What is one benefit of cloning plants from stem cells?
Producing large numbers of rare plants reliably and safely
In what field is the cloning of plants from stem cells used to produce disease-resistant crop plants?
Agriculture
What can the process of cloning plants help save?
Rare plants from extinction
What is one application of stem cells in horticulture?
Producing large numbers of plants like orchids
True or False: Stem cells have no potential use in treating conditions like dementia.
False
What are the potential benefits of using stem cells in human medicine?
They are gradually being used to treat real patients.
What are some practical risks associated with stem cell technology?
Social and ethical issues.
Where do embryonic stem cells come from?
Aborted embryos and spare embryos from fertility treatment.
What is a key advantage of embryonic stem cells?
They divide and grow rapidly.
What is a disadvantage related to the use of embryonic stem cells?
Embryos cannot give permission for their use.
What ethical concern is raised by the use of embryonic stem cells?
Violation of the embryo’s human rights.
What is a potential health risk of using adult stem cells?
Risk of being infected with viruses.
What may be required if adult stem cells trigger an immune response?
Immunosuppressant drugs.
What do some critics believe about the funding of stem cell research?
Money is wasted and should be spent on other areas of medicine.
What are some sources of embryonic stem cells that may help overcome ethical concerns?
Umbilical cord blood and amniotic fluid.
What is a potential benefit of using adult stem cells?
Avoids controversial use of embryonic tissue.
What has therapeutic cloning the potential to create?
Perfectly matched embryonic stem cells.
What is one application of stem cells discovered in tubes connecting the liver and pancreas?
Turning into insulin-producing cells.
Which condition has been treated using stem cells in diabetic mice?
Type 2 diabetes.
What are some potential therapies being researched using stem cells?
Spinal cord injuries, diabetes, heart damage, eyesight restoration, damaged bone and cartilage.
True or False: Progress in stem cell research has been fast and easy.
False.
Fill in the blank: Embryonic stem cells may cause _______ if used to treat people.
cancer
