Cell division (green) Flashcards
(22 cards)
What is a gene?
A section of DNA that codes for a specific protein to be made
How many chromosomes are found in human body cells?
46 (or 23 pairs)
What are the sex chromosomes in biological females?
XX
What are the sex chromosomes in biological males?
XY
When do cells divide by mitosis?
- When an organism grows
- When tissues are repaired
- During asexual reproduction
What is the first stage of the cell cycle?
Cell growth
What happens during the DNA synthesis stage of the cell cycle?
Chromosomes become double stranded
How many daughter cells are produced in mitosis?
Two
In mitosis, daughter cells are genetically _________ to the parent cell.
Identical
What is a stem cell?
An undifferentiated cell
Where can adult stem cells be found in the body?
- Bone marrow
- Brain
- Skin
- Heart
- Blood
- Liver
- Muscle
Adult stem cells in bone marrow can differentiate into…
Blood cells
What is the name for the regions found in plants where cell division occurs?
Meristems
Where are meristems mainly found in plants?
Roots and shoots
Describe the steps to cloning in plants.
- Meristem cells removed from plant.
- Cells grown in Agar growth medium (contains nutrients and plant hormones).
- Plantlets are removed and planted.
What is a desirable characteristic that plants may be cloned for?
Disease resistance
Describe three ways that stem cells could be used in human medicine.
- in Type 1 diabetes
- in cases of multiple sclerosis, which can lead to paralysis
- in cases of spinal cord or brain injury, that have led to paralysis
What are the two kinds of stem cells that could be used in medical treatments?
Embryonic stem cells, adult stem cells
What is a benefit of using embryonic stem cells in medical treatments?
They can differentiate into a wider range of cell types, so can be used to treat a wider variety of diseases
What is a disadvantage of using embryonic stem cells in medical treatments?
They are difficult to obtain
Their use raises ethical dilemmas (e.g. potential life is killed)
What is an advantage of using adult stem cell transplants?
They use the patient’s own cells, so they will not be rejected by the patient’s immune system
What is therapeutic cloning used for?
To produce stem cells with the same genetic make-up as the patient
