Genetics: Mutations Flashcards
What is a mutation?
A mutation is a change in the genetic makeup of an organism
What is a gene mutation?
A gene mutation is what occurs when there is a change in the sequence of nucleotides in the DNA. This causes a change in the information that the gene should give to the cell
What causes mutation?
1 Chance
2 crossing over ( of paternal and maternal chromosomes)
3 replication ( of DNA)
4transcription
What are point mutations and how many types are there?
Point mutations are mutations that affect one or only a few nucleotides. The different types are: -deletion -insertion -substitution
What are large mutations?
Mutations that affect more than one nucleotide. they can lead to the rearrangement of nucleotides or to the creation of new genes
What are mutagens?
They are the factors that increase the chance of mutation. Some examples are chemicals, radiation and viruses
Do neutral and beneficial mutations occur?
YEs they do occur, although they occur seldom. an example is the super bug, which has become immune to certain antibiotics ( beneficial mutation for the bug, not for us humans however)
What is albinism caused by?
Melanine protects the body from ultraviolet rays. Albinism occurs when there is a block in the area where melanin is formed, not allowing for the correct distribution and formation of it.
What does albinism cause?
pink skin
light/white hair
irises that are white or light blue
vision deficiencies
What is sickle cells disease?
a disease where red blood cells loose their round shapes and collapse
Is it an inherited disease? If so explain how so.
It is an inherited disease as it occurs when the offspring inherits both the recessive allele for normal haemoglobin
What are the symptoms of Sickle cells disease?
anemia ( less presence of oxygen)
pain, fever, swellings, tissue damage
red blood cells loose their shape
