Nutrition and Genetics Flashcards
What is DNA?
Deoxyribonucleic acid (DNA) contains the instructions for the development, growth, function and reproduction of cells and therefore entire organisms

Who discovered DNA?
Watson & Crick
What are the 4 base pairs?
What is the other base pair seen in RNA (replaces thymine)?
A - Adenine
T - Thymine
G - Guanine
C - Cytosine
U - Uracil
What is a genome?
The total of all genes
How many base pairs in the human body?
approx. 3 billion
When did the human genome start and end?
1990-2013 (10 years ahead of schedule
How many pairs of chromosomes does a human possess?
23 pairs
(46 individual)
Which chromosome pairs are the autosomes?
pairs 1-22
Which chromosome pairs are the sex chromosomes?
pair 23
What is the chromosome sequence for males and females?
Female - XX
Male - XY
Which pair of chromosomes are affected to cause down syndrome? How?
pair 21 extra chromosome (3 total)
What is a gene?
basic unit of hereditary, codes for a specific trait
What is a allele?
two or more versions of a gene
What is the difference between a homozygous and heterozygous gene?
Homozygous: You inherit the same version of the gene from each parent, so you have two matching genes.
Heterozygous: You inherit a different version of a gene from each parent. They do not match.
What is the difference between genotype and phenotype?
Genotype - Genetic make-up on an individual -not always an observable characteristic
Phenotype - The observable characteristics of an individual resulting from the genotype
Genes can vary in 3 differing locations of DNA. Where?
- Single nucleotide - (base change, insertion, deletion)
- Groups of nucleotides (repeats)
- Whole chromosome (insert, deletion, rearranging)
What gene has had associations with obesity?
FTO gene
What are the structural differences between DNA and RNA?
DNA -
Deoxyribose sugar
double stranded
thymine base
RNA -
Ribose sugar
single stranded
uracil base
comprises mRNA, tRNA, rRNA
What is gene expression?
The conversion of information encoded in a gene > mRNA > protein
What determines the structure of a protein?
DNA base codes
What is a sequence of 3 base codes called?
A codon
Are all amino acids coded for using only 1 codon?
No, some amino acids can have multiple codons.
E.g. proline can be coded by codons; CCG, CCU, CCC OR CCA
What organelles are the site of protein synthesis? Where does this occur?
Ribosomes
In the nucleus of the cell
What is transcription? (protein synthesis)
The process of making an RNA copy of a gene sequence, results in a copy called mRNA

