DNA and Genetics Flashcards
What does DNA stand for?
Deoxyribose Nucleic Acid (Deoxyribonucleic Acid)
Where is DNA present?
Inside the nucleus of cells in all living organisms
Does DNA control all chemical changes?
Yes
What is DNA made up of?
A long chain of nucleotides
How many parts make up a nucleotide, and what?
3 parts:
1. A sugar, deoxyribose
2. A phosphate, PO4
2. An organic base
What is DNA?
A complex and large molecule
What is the difference between a ribose and a deoxyribose?
A ribose only has five carbon atoms in its molecule while deoxyribose lacks one oxygen atom.
What symbol both represents the molecules ribose and deoxyribose?
A pentagon
The 4 most common organic bases?
- Adenine (A)
- Thymine (T)
- Cytosine (C)
- Guanine (G)
What forms a nucleotide?
A deoxyribose, A phosphate - PO4 and one of the organic bases
What gives DNA its acidic properties?
The phosphate groups
How is a molecule of DNA formed?
A molecule of DNA is formed by millions of nucleotides joined together in a long chain
What does DNA usually consist of?
A double strand of nucleotides
Where are the sugar-phosphate chains located?
On the outside
What are strands held together by?
Chemical bonds between the organic bases
What are the base pairings?
Adenine (A) and Thymine (T).
Cytosine (C) and Guanine (G).
What do the paired strands coil into a spiral called?
A double helix
What is the shape of DNA?
A double helix
What happens before a cell divides?
The DNA strands unwind and separate
Describe the process replication?
Before a cell divides, DNA unwind and separate. Each strand makes a new strand by adding the appropriate nucleotides. Resulting in two new double-stranded DNA molecules in the nucleus.
Where are the nucleotides present in?
Nucleotides are present in nucleoplasm. Which is the nuclear equivalent of cytoplasm.
What do the sequence of bases in DNA form?
Genetic code
What is a triplet?
A group of 3 bases
What does a triplet control?
Controls the production of a particular amino acid in the cytoplasm of the cell
What determines the sort of protein being produced?
The different amino acids and the order they are joined up determines the sort of protein being produced.
What does CAT code for?
Valine
What does CGA code for?
Alanine
What is triplet code?
A group of 3 bases codes for a specific amino acid
When does replication of DNA occur?
Before cell division
When amino acids are joined together in the correct sequence, what do they make?
Part of a protein
How are parts of a protein formed?
When amino acids are joined together in the correct sequence.
Where does the protein build-up take place?
In the cytoplasm
What does RNA stand for?
Ribo-nucleic acid
The DNA of the nucleus makes a single…
The DNA of the nucleus makes a single strand of messenger RNA
How can RNA leave the nucleus?
Due to how small they are. They can fit through tiny pores in nucleus, out to the cytoplasm.
What is the RNA code? Complementary or identical to the nuclear DNA?
Complementary
What do the proteins build?
The proteins build the cell structures
What do proteins also make aside from cell structures?
Enzymes
The DNA controls which …. are made and the …. determine what ….. take place
The DNA controls which enzymes are made and the enzymes determine what reactions take place.
What do enzymes determine?
Enzymes determine what reactions take place
What do the structures and reactions in the cell determine?
They determine what sort of a cell it is and what function it is
How does DNA exert control?
DNA exerts control through the enzymes
What does a sequence of triplets in the DNA molecule may code for?
A complete protein, such a sequence forms a gene
How many bases in one gene?
There may be a thousand or more bases in one gene
How does mutations affect triplet code?
Mutations can change letters around which may code different amino acids or STOP which ends the sequence of amino acids.
messenger RNA in short
mRNA
What type of RNA assembles the protein, one amino acid at a time?
Transfer RNA (tRNA)
Each sequence of three nucleotides is called …
A codon
What is a gene?
A section of DNA that codes for a protein
Inside a gene, codes vary in what?
Length
Explain what is meant by DNA being a “blueprint for a living thing”?
DNA is the basic, compulsory coding that every organism must have in order to get created. DNA is the building blocks for a living thing, essentially makes living things what they are.
Describe the structure of DNA and the possible base pairs it contains.
The structure of DNA is a double helix or a twisted ladder and the possible base pairs are A and T, C and G
If 30% of the bases in a particular DNA molecule are guanine (G), calculate the percentage of the bases would be thymine (T). Explain your reasoning.
Since 30% of bases are guanine (G), that means its pair, cytosine (C) would also be 30%; making 60% of the DNA already leaving 40%. The 40% is split across Adenine (A) and Thymine (T) each having 20%. So, Thymine would have 20%.
A raven’s claws are made out of the protein keratin. Describe how this fact is related to the raven’s genes.
The raven’s genes are what codes for the protein Keratin.
Define Sex-linked inheritance
Characteristics or traits which are influenced by genes carried on sex chromosomes
Define autosome inheritance
the gene is located on one of the autosomes
