B2.5 Flashcards
Why are cells needed?
For an organism or part of an organism to grow.
What is mitosis?
Cell division in normal body cells that produces two identical cells.
What does mitosis work?
Produces new copies of the chromosomes in the mucked before a cell divides. Then the cell divides once to form two genetically identical cells.
What is meiosis?
Sex cells with only half the original number of chromosomes.
How are gametes formed?
By meiosis.
What are the names of the male and female gametes in animals? How do they differ from normal body cells?
Sex cells.
They continue random mixtures of the original chromosomes pairs.
Introduces variety.
What type of cell divisionism needed to produce gametes?
Meiosis.
What are stem cells?
Inner cells of a hollow ball of cells.
What was the big scientific breakthrough by American scientists in 1988?
Two American scientists managed to culture human embryonic stem cells. These were capable of forming other types of cells.
What is the biggest ethical concern with the use of embryonic stem cells?
Using it is a violation of its human rights.
Embryonic stem cells might cause cancer if they’re used to treat sick people.
Why did Gregor Mendel become a monk?
To get an education.
What was unusual about Mendel’s scientific technique at the time?
Explained some of the basic laws of genetics using mathematical models in ways that we still use today.
Model was ahead of time.
Twins are born. Twin A is XY and twin B is XX. What sex are the two babies?
Female and male.
What is homozygous?
Individual with two identical alleles for a characteristic.
What is heterozygous?
Individual with different alleles for a characteristic.
What is genotype?
Describes the genetic makeup of an individual regarding a particular characteristic.
What is phenotype?
Describes the physical appearance of an individual regarding a particular characteristics.
What is a recessive allele?
Lower case letter eg d.
What is a dominant allele?
Upper case eg D.
How is an inherited disorder different from an infectious disease?
Inherited has been passed on from genes but infectious is from things such as direct contact and droplet infections.
What is polydactyl?
Babies being born with extra fingers or toes.
What is he most common form of polydactyl?
Caused by a dominant allele.
What is cystic fibrosis?
Genetic disorder that affects many organs of the body.
What are the main organs that cystic fibrosis affects?
Lungs and pancreas.
What happens to your organs if you have cystic fibrosis?
They become clogged up by thick, sticky must us which stops them from working properly.
What allele causes cystic fibrosis?
Recessive alleles.
Must be inherited.
What is a carrier?
They are carrying the recessive allele which they will pass on.
Why will people only inherit cystic fibrosis if they get that allele from both parents?
Because it is a recessive allele.
