Protein Synthesis Flashcards
Where are:
Chromosomes found
Nucleus
What is:
DNA?
- Long list of instructions on how to put an organism together and make it work
- Deoxyribose Nucleoid Acid
What is a:
gene
A section of DNA that codes for one protein
What is the:
Structure of DNA
- Double helix
- Has two strands which are in a helix structure
- Held together by chemicals called bases (there r 4)
What are the different:
Bases
- adenine (A)
- cytosine (C)
- guanine (G)
- thymine (T) (Uracil in mRNA U)
- A always pairs with T and G always pairs with C
- This is called complementary base pairing
What is:
Protein Synthesis
- Made in Two Steps - Transcription and Translation
- This process makes proteins which determine how cells function
What is:
cytoplasm
site where most chemical reactions take part in the cell
What is a:
Cell
The basic unit of all living organisms
What is a:
Chromosome
Long lengths of DNA coiled up
What is:
DNA
Smallest unit of genetic material, a polymer from monomers called nucleotides, which join to make a polynucleotide
What is:
Genome
All of the genes in an organism
What is an:
Allele
Different version of a gene that codes for a different version of a characteristic
What is:
Homozygous
When the alleles are in a matching pair
What is:
Heterozygous
When the alleles are not in a matching pair
What is a:
dominant allele?
This is the characteristic which is always present int the phenotype and represented by a capital letter
What is a:
Reccessive allele
Opposite to dominant, only shown in phenotype if it is homozygous, represented by a small letter
What is:
Genotype
the allele pair for each characteristic
What is:
Phenotype
the physical expression of an allele pair
What is:
Monohybrid inheritance
This is the inheritance of a single gene. Outcomes of monohybrid crosses can be figured out with genetic diagrams and punnett squares and predict probabilities
What is:
Co-dominant allele
When two alleles are equally dominant and both expressed in the phenotype
What are the two parts and the purpose of:
Protein synthesis
- Transcription
- Translation
The DNA stays in the nucleus but the code travels into the ribosome where proteins are assembled using mRNA and tRNA
PRACTICE DRAWING STRUCTURE
What is a:
DNA strand
A template strand for each protein which gives instructions
This can make hormones, enzymes or structural proteins
How many different:
amino acids, nitrogenous bases needed to code for an amino acid
20 different amino acids (some are repeated)
3 nitregenous bases code for each amino acid, this is the same in all organisms so it is a universal code
Differences between:
DNA and RNA
- DNA is a double helix whereas RNA is a single strand
- DNA contains the sugar deoxygribose whereas RNA has ribose
- DNA contains the base Thymine but RNA contains Uracil
What is:
Transcription steps
- Part of the DNA helix is unwound
- RNA nucleotides line up along the template strand, according to complementary base pairing
- The sugar phosphate backbones join up forming a mRNA molecule
- The DNA code has been trasnferred into a messenger molecule, which leaves the nucleus through a nuclear pore
PRACTICE DRAWING TRANSCRIPTION
What is a:
Punnett square
A box showing the probabilities of what allele/gene will be inherited based on the parents’ genotype.
Who advanced the field of:
Inheritance
Gregor Mendel, through experimenting with peas
Notation for:
Co-dominance
BB BW WW
X X X X X X
or BB BW WW
What is a:
Family pedigree
A chart which shows how genetic disorder are inherited in a family, which can be used to find the probability of inheriting a condition
What is the cause of:
Variation
A mix of genetic and environmental
e.g. sex is genetic, piercings are enviromental and height is both
Variation in offspring is due to the random fertilisation of gametes
Some characteristics are also determined by multiple genes which lead to polygenic inheritance
What is a:
Diploid, haploid nucleus
A nucleus containg two complete sets of chromosomes, with one from each parent
hapolid nucleus is a signle set of unpaired chromosomes
What is the steps of:
Translation
- Translation converts mRNA into protein at the ribosomes
- Each triplet code on the mRNA (codon) lines up on the ribosome and is matched by a tRNA molecules with a complementary anti-codon at the end
- The other end of the tRNA holds a specific amino acid, determined by the anti-codon
How do:
Amino acids form proteins
- codon AUG on the mRNA is the start codon, with the complementary tRNA molecules bringing the amino acid required. This process repeats itself based on the next codon/anti-codon pairing
- A bond forms between the 2 amino acids
- The first tRNA is released and goes back to collect another amino acid
- More tRNA molecules arrive, bringing amino acids to the polypeptide chain which forms the protein
- At the end, a stop codon indicates that translation is complete.
Why might:
A mutation have little effect on the phenotype of an organism?
There are 64 possibilities of codons, but only 20 amino acids, so a change in a codon might not lead to a change in the amino acid and therefore protein made.
What is a:
Mutation
A change to the base sequence of DNA
What is:
Huntington’s disease
- A dominant characteristic
- Neurological disease
- Appears after the age where most have children
What is:
Cystic fibrosis
recessive genetic disorder affecting lungs
What is:
Polygenic inheritance
single inherited phenotypic trait that is controlled by two or more different genes
