Genetic Information Flashcards
What is DNA like in Prokaryotic Cells?
. short
. circular
. not associated with proteins
. naked
What is DNA like in Eukaryotic Cells?
. long
. linear
. associated with proteins (histones) to make chromosomes
. found inside the nucleus
What are the bases in DNA and how do they pair?
. Cytosine(C)
. Guanine(G)
. Adenine(A)
. Thymine(T)
Pairing: C-G, A-T, G-C, T-A
What are the bases in RNA and how do they pair?
. Cytosine(C)
. Guanine(G)
. Adenine(A)
. Uracil(U)
Pairing: C-G, A-U, G-C, U-A
How does a phosphodiester bond is formed between two nucleotides?
Condensation occurs which means a water molecule is lost between the pentose sugar (ribose or deoxyribose) and the phosphate group. This reaction is catalysed by the polymerase.
What are the differences between RNA and DNA?
- RNA’s pentose sugar is ribose and DNA’s is deoxyribose
- RNA has uracil instead of thymine (like in DNA) as their bases
- DNA hold genetic information but RNA transfers that information from DNA to ribosomes for protein synthesis
- DNA always has hydrogen bonds but not the case for RNA
- Only one type of DNA but multiple of RNA
- DNA is double stranded and RNA is single
What do genes code for?
- a functional RNA (including ribosomal RNA and tRNAs)
- amino acid sequence of a polypeptide
What is the functions of DNA molecule?
It contains the genetic information and it determines our inherited characteristics
What is the structure and functions of RNA molecule?
- It RNA transfers that information from DNA to ribosomes for protein synthesis
- single stranded
- has ribose for pentose sugar
- one of 4 bases (G,C,A,U)
What are purine bases?
Bases with double ring structure (A and G)
What bases are pyrimidines bases?
Bases with single ring structure (T, U, C)
What are the features of the genetic code?
- non-overlapping
- universal
- genes are separated by non-coding repeats of bases
- degenerate
- contains start and stop codons
How the structure of the DNA is related to it’s function?
- long so lots of info can be stored
- helix/coiled so it’s compact
- sugar-phosphate backbone protects the bases which allow information to be stored
- double stranded so replication can occur semi-conservatively
- weak hydrogen bonds for easy replication
What are the differences between mRNA and tRNA?
- mRNA has no hydrogen bonds but tRNA does
- mRNA is linear but tRNA has a cloverleaf shape
- tRNA has amino acid binding site but mRNA doesn’t
- mRNA has more nucleotides
- mRNAs can have different lengths but tRNA are all similar in length
- tRNA have anticodons but mRNA have codons
What is the function of tRNA?
It transports a specific amino acid to the ribosome and it associates with it
What is the function of mRNA?
It copies DNA and transfers it to the ribosome
What is the function of rRNA?
It’s where protein synthesis occurs
What are the features of tRNA?
- has an amino acid binding sight (complementary)
- one end is an anticodon
- has a compact, cloverleaf shape
- have hydrogen bonds
- are all similar in length
What are the features of mRNA?
- found in the nucleus and cytoplasm
- long, linear and complementary
- created during transcription
- no hydrogen bonds
- are all different lengths
- have codons
What are the features of rRNA?
found in the cytoplasm (ribosomes)
how many amino acids regularly occur in proteins?
20
how many how many codes can be produced from 2 bases?
16 (inadequate amount)
how many how many codes can be produced from 3 bases?
64
what is a locus/loci
the fixed position occupied by a gene on a DNA molecule
