Chapter 2 - Summary Questions Flashcards
Where are chromosomes found?
In the nucleus.
Name the chemical that forms a gene?
DNA (Deoxyribonucleic acid).
Which type of cell division produces two identical cells?
Mitosis.
How many chromosomes are found in the nucleus of a human sperm cell?
23.
Name the tissue that continues to divide in plants.
Meristem.
Give one place where stem cells are found in adult humans.
Bone marrow (this is the main source currently, though the stem cells have been found in other places, such as the liver, blood, brain and muscles).
Name two medical conditions that could be treated with stem cells.
Two from: paralysis, type 1 diabetes, blindness, heart damage, bone damage.
Describe what happens when a cell differentiates.
An unspecialised cell changes into a specialised cell (such as a muscle cell or a nerve cell)
State two uses of cloning in plants.
Two from: to save rare plants from extinction; for research using genetically identical plants; in horticulture, to produce large numbers of plants cheaply; in agriculture, to produce disease-resistant crops.
What is therapeutic cloning?
An embryo is produced that has the same genes as the patient, so the stem cells produced are not rejected (and may be used for medical treatment).
Give two reasons why some people object to the use of stem cells.
Two from: violation of embryo’s rights; religious objections; money could be better spent on other medical research; process of differentiating stem cells is difficult and expensive; rapidly dividing stem cells could cause cancer; adult stem cells could transmit values or trigger an immune response.
Suggest why scientists are finding it difficult to produce nerve cells from stem cells.
It is difficult to work out the complex mechanisms that trigger the stem cell to differentiate.
