N4 Unit 1 Part A Flashcards
Which part of the cell controls cell division?
Nucleus
Why is cell division important to animals?
For growth and repair
What are chromosomes?
X shaped structures found in the nucleus
What effect does cell division have on the number of chromosomes in a cell?
It stays the same
What name is given to the middle area of the cell?
Equator
What name is given to either end of the cell?
Poles
Name the structures which pull chromatids apart.
Spindle fibres
What structure holds the chromatids together in a chromosome?
Centromere
What disease is caused by uncontrolled cell division?
Cancer
If cancer cells grow together they may form a mass, what is this mass of cells known as?
Tumour
Where is DNA found within the cell?
Nucleus
Name the two parts of a DNA molecule.
Backbone and bases
Which part of the DNA molecule contains the genetic information?
Bases
What is a gene?
Instructions to make a protein.
How does DNA fit into the nucleus of a cell?
It is tightly coiled into chromosomes.
What are the four base letters of DNA?
A, T, G and C
Where do we inherit our DNA from?
From our parents.
If a gene is faulty what effect does this have on the protein it produces?
A faulty protein would be produced.
What causes genetic diseases?
A faulty gene.
Give one example of a genetic disease.
Cystic fibrosis.
What are stem cells?
Cells which cab turn into any type of body cell.
What two processes within the body require stem cells?
Growth and repair
What is meant by the term “therapeutic uses of stem cells”?
Using stem cells in medicine to treat diseases.
Name and describe one current use of stem cells in medicine.
Bone marrow transplant to treat leukaemia.
What is a plasmid?
A small ring of DNA
What is genetic engineering?
The transfer of genetic information from one cell to another.
Name one substance which can be made by genetic engineering.
Insulin
What term describes an organism which has had its genetics artificially altered?
Genetically modified organism (GMO)
Which stage of genetic engineering occurs after the gene has been extracted and a plasmid cut open?
The gene is inserted into the plasmid.
What is the function of enzymes?
They speed up chemical reactions and are unchanged in the process.
What is the active site?
The part of the enzyme where the substrate binds.
What is a substrate?
The substance an enzyme acts upon.
What does specific mean in relation to enzymes?
It means each enzyme will only catalyse one chemical reaction
Which enzyme breaks down starch into maltose?
Amylase
What is a synthesis reaction?
A build up reaction
What is a degradation reaction?
A break down reaction
Name an enzyme which carried out a synthesis reaction.
Phosphorylase
Name an enzyme which carried out a degradation reaction.
Catalase
What is an enzymes optimum temperature?
The temperature where the enzyme is most active.
What happens to the shape of an when it becomes denatured?
The shape of the active site changes so the substrate no longer fits with the enzyme.
What happens to an enzyme when it is pushed far above its optimum temperature?
It becomes denatured
Name a product made using enzymes and the name of the enzyme used.
Cheese is made using rennet
