Human Biology Flashcards
What is differentiation?
Differentiation is when unspecialised cells such as stem cells have genes switched on so they can perform a specific function or role within the body.
Give an example of a differentiated cell type.
Nerve cells, red blood cells, cardiac muscle cells
What method do somatic cells use to divide?
Somatic cells divide by mitosis
What method do germline cells use to divide?
Meiosis
How would we describe the chromosome compliment of somatic cells after cell division?
Somatic cells would be described as diploid after cell division
How would we describe the chromosome compliment of germline cells after cell division?
Germline cells would be described as haploid after cell division
If a mutation occurs in a somatic cell line what impact would it have?
A mutation in the somatic cell line would directly affect the individual.
If a mutation occurs in the germline cell line what impact would it have?
A mutation in the germline cell line would have an impact on the offspring
What is a benign tumour?
A benign tumour is a uncontrolled growth of cells that remains in one place
What is a malignant tumour?
A malignant tumour is an uncontrolled growth of cells, eg cancer that breaks through the cell membrane and detach, spreading through the body.
Identify the base pairing in DNA
In DNA, adenine pairs with thymine, and cytosine pairs with guanine
What are the differences in bases between DNA and RNA?
In RNA thymine is replaced with uracil
What type of bonding holds the complimentary base pairs together?
Hydrogen bonding holds the complimentary base pairs together, it is a weak bond and once it breaks it allows DNA to unzip
What type of bonding holds the phosphate and sugar together in a DNA strand?
A phosphodiester bond holds the sugar and phosphate together. This is a strong bond and helps support and maintain the backbone of the structure.
What type of sugar is present in DNA molecules?
Deoxyribose sugar is present in DNA molecules.
What type of sugar is present in RNA molecules?
Ribose sugar is present in RNA molecules
DNA is described as antiparallel, what does this mean?
One strand of DNA runs in the 5’ to 3’ direction, and the other strand runs in the 3’ to 5’ direction
How are fragments made in the lagging strand of DNA?
Fragments are made at the lagging strand of DNA due to primers only being able to anneal (join) at the replication fork. More primers are added as the DNA strand continues to unzip.
Where does transcription take place?
Transcription takes place in the nucleus of the cell.
What is the starting molecule of transcription?
The starting molecule of transcription is DNA.
What is the product of transcription?
A strand of mRNA is the product of transcription?
What are the building blocks of mRNA
The building blocks of mRNA are ribonucleotides.
Where does translation occur?
Translation occurs at the ribosomes
What is the starting molecule of translation?
The starting molecule of translation is mRNA