3. DNA and the Production of Proteins Flashcards
Where do we we find DNA?
In the nucleus
Define DNA
A special molecule which provides the instructions for a living thing.
What does DNA stand for?
DeoxyriboNuleic Acid
What is a chromosome?
Thread-like structures containing many genes stored in the nucleus of cells.
(DNA is a very long because there are many instructions needed to make a living thing. To get all of these instructions to fit into a tiny cell the DNA is wound up very carefully into chromosomes).
Where do we get chromosomes from?
Chromosomes are inherited (passed down) from parents to children.
We get 23 chromosomes from our mother and 23 chromosomes from our father.
What are genes and what are they for?
Genes are sections (BANDS) of chromosomes made of chains of DNA.
Genes code for a particular protein (e.g. enzymes or hormones) or characteristic.
List five characteristics we could have passed down from our parents
These could include…
height, eye colour, skin colour, absence or presence of freckles, hair texture, ability to roll tongue, blood group, shoe size, if your ears are attached or lobed, ability to do a hitch hikers thumb or not…. and much much more.
How many chromosomes do humans have?
46
A gorilla’s body cells each contain 48 chromosomes. How many chromosomes did the gorilla inherit from its mother?
24
half from mum, half from dad
Describe the structure of DNA
DNA has a double helix shape, which is like a ladder twisted into a spiral. The double helix is made of with two strands held together by weak hydrogen bonds between the bases.
Each step of the ladder is a pair of bases,
How many bases are there and what are their names?
There are 4 bases.
Adenine
Thymine
Cytosine
Guanine
When discussing base pairs what does complementary mean?
The bases are COMPLEMENTARY to each other. This means that A is always paired with T and C is always paired with G
What pairs with Thymine?
Adenine
What pairs with adenine?
Thymine
What pairs with cytosine?
Guanine
What pairs with Guanine?
Cytosine
Past Paper Question1
What is the full name of base 1
Guanine
Why is DNA useful in forensic science?
Because no two people have identical DNA, it can be useful evidence to put an individual at the scene of a crime.
How does DNA differ from person to person?
The order of the DNA base pairs differ
What parts of the body can we collect DNA samples from?
Blood, saliva, bone marrow and skin
What is DNA Finger Printing?
A DNA fingerprint, or DNA profile, is a laboratory technique. It produces a picture with lots of lines (bands) on it.
Each person has a unique DNA fingerprint, because their DNA is unique.
List 3 uses of DNA fingerprinting
DNA fingerprinting can be used to solve crimes, detect disease or in paternity cases (finding out who someone’s father is).
What is the genetic code? (remember BAP)
BAP…. Bases—–>Amino Acids—–>Protein
B(ases) ….The order of DNA Bases encodes information for the sequence of
A(mino acids) in a protein. The sequence of amino acids dictates the structure and function of the
P(rotein).
Where is DNA found in the cell?
Nucleus
What is the site of protein synthesis in the cell?
Ribosome
If DNA is in the nucleus and the protein is made at the ribosome, how does the cell know which amino acid goes where?
Because of mRNA
What does the M of mRNA stand for?
Messenger
What does mRNA carry?
A copy of the DNA genetic code from the nucleus into the cytoplasm of a cell.
What happens when mRNA meets a ribosome in the cytoplasm?
The amino acids become assembled to make a protein.
Past pper question!
Name molecule P
mRNA
Past pper question!
What molecules are represented by AA?
Amino Acids
