Genetics Flashcards
What is a chromosome?
A long molecule of DNA.
What is a gene?
A section of a chromosome.
Where is the genetic information found in a cell?
In the nucleus.
What is the role of a gene?
It contains the instructions to make a specific protein.
What are proteins made up of?
Chains of amino acids
Is everyone’s DNA unique?
No. Clones and identical twins have the same DNA.
Why can DNA fingerprinting be used?
Each person has a unique pattern which means that you can tell people apart by comparing samples of their DNA.
Give two examples of where DNA fingerprinting can be used in real life.
Forensic science and paternity testing.
What is mitosis used for?
To generate identical body cells for growth and repair.
How many daughter cells are created by the process of mitosis?
2 genetically identical body cells.
How many chromosomes do cells made by mitosis contain?
23 pairs.
What type of cell division does asexual reproduction use?
Mitosis.
Is there genetic variation between offspring created by asexual reproduction?
No. Mitosis results in identical cells so there is no variation.
What is meiosis used for?
For creating gametes.
Where does meiosis take place?
In the ovaries and testes.
How many daughter cells are created by meiosis?
4 genetically different daughter cells.
How many chromosomes do cells made by meiosis contain?
23 chromosomes (not pairs!!)
Why do sperm and egg cells only contain 23 chromosomes and not 23 pairs?
Because at fertilization, the sperm and egg fuse to create an embryo that contains 46 chromosomes, half from the mother and half from the father. This gives variation in the offspring.
How many divisions are there in meiosis?
Two.
What are stem cells?
Undifferentiated cells
Where are the two places that stem cells can be found?
Adult bone marrow `and embryos.
Give two examples of uses for stem cells.
To cure paralysis and to treat blood conditions
What do researchers have to do in order to get cultures of one specific type of cell?
Control conditions and environment that they are grown in.
Give a reason as to why some people are against stem cells research.
They feel that human embryos shouldn’t be used for experiments since each one is a potential human life
Do males have XX chromosomes or XY?
XY
Do females have XX chromosomes or XY?
XX
What do genetic diagrams show?
The possible combinations of gametes.
Who was Mendel?
Mendel was a Austrian monk who did work on genetics and variation
True or False. At the time that Mendel was investigating genetics, his results were taken seriously.
False
What did Mendel call genes?
Hereditary units
What did Mendel say about which characteristic would be shown?
The dominant gene will be shown unless there are two recessive genes.
What are alleles?
Versions of a gene.
What type of allele causes cystic fibrosis?
Recessive
What part of the cell does cystic fibrosis affect?
Cell membranes.
What does cystic fibrosis result in?
It results in the body producing a lot of thick sticky mucus in the air passages and in the pancreas.`
What type of allele causes polydactyly?
Dominant
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