Yr I Chemistry & Biochemistry II Flashcards
What are amino acids?
Building blocks of proteins
Which 4 elements form amino acids?
Carbon, hydrogen, oxygen and nitrogen
Which element distinguishes amino acids from fats and carbohydrates?
Nitrogen
How many different amino acids does the body need?
20
Which 2 groups does each amino acid have?
Carboxyl group (acid) COOH
Amino group NH3
What determines the characteristics of each amino acid?
Side chain labelled R
How do amino acids join together?
Dehydration synthesis (removing water) to create peptide bonds
Name 2 amino acids joined
Dipeptide
Name 3 amino acids joined
Tripeptide
Example of a harmful dipeptide
Aspartame
Why is aspartame harmful
Neurotoxin excited brain cells
Carcinogenic
Example of a powerful antioxidant tripeptide?
Glutathione
Which 3 amino acids does glutathione contain?
L-cysteine
L-glutamate
L-glycine
Which amino acid commonly limits glutathione production?
L-cysteine
3 L-cysteine rich foods
Legumes
Sunflower seeds
Eggs
What affects the 3d structure of amino acids and therefore their function
Th surrounding fluid’s pH
Example of an amino acid changing structure
Ceviche - acid turns fish opaque
What can amino acids with acidic side chains do?
Release hydrogen ions
What can amino acids with basic side chains do?
Bind to hydrogen ions
Which type of amino acid is hydrophobic
Non polar amino acids
Which type of amino acid is hydrophilic?
Polar
Example of a non-polar (hydrophobic amino acid)
Tryptophan - used to produce serotonin to stimulate gut motility and digestive juices
Example of a polar (hydrophilic) amino acid
Tyrosine - used to create adrenaline and thyroxine.
What determines the unique shape of a protein?
Combination of polar and non polar amino acids
What are haemoglobin, ferritin, albumin, collagen and insulin
Types of protein
5 functions of protein
- body structure
- movement - actin and myosin
- storage - ferritin
- carrier - haemoglobin
- enzyme reactions in the body
2 factors that can denature proteins
Heat
Heavy metals
Example of a protein being denature by heat
Egg white
What heavy metals can denature proteins in the body
Lead and mercury
2 chelating agents that can bind to heavy metals in the body
Coriander and chlorella
What does the body use to help digest proteins and break down the peptide bonds in amino acids?
Enzymes
What type of reaction can help break the bonds in proteins
Hydrolysis
Where does the body start to break down proteins?
In the mouth. Chewing increases the surface area
Where does the chemical digestion of proteins begin?
In the stomach
Which enzymes breaks down long protein chains in the stomach
Pepsin
Where is pepsin released from
Chief cells
What is the inactive form of pepsin
Pepsinogen
What pH does pepsin need?
pH 2
What triggers the release of pancreatic juices in the small intestine?
Hormone called CCK
2 proteases in the pancreatic juices
Trypsin and chymotrypsin
What do longer protein chains get broken down into in the small intestine
Tripeptide, dipeptides and single amino acids by brush border enzymes
What breaks down amino acids in the small intestine
Pancreatic proteases (trypsin and chymotrypsin)
&
Brush border enzymes
Where are small peptides and amino acids absorbed into from the digestive tract?
The blood
2 most common nucleic acids
DNA deoxyribonnucleic acid
RNA ribonucleic acid
What are the building blocks of nucleic acids called?
Nucleotides
3 x parts of a nucleotide?
Phosphate group
Sugar
Nitrogenous base
What is the function of nucleic acid?
Store genetic information
What cell does not contain dNa
Red blood cell
How long would a dna molecule be?
2m
What does DNA act as a template for?
Protein synthesis
What does RNA do?
Copy specific sections of DNA called genes
How many genes in a human genome (complete set of DNA)
20-25k
What is the human genome?
Complete set of DNA
What is deoxyribose
5-carbon sugar
What are the 4 nucleotide bases in DNA
Adenine
Thymine
Guanine
Cytosine
Which 2 nucleotide bases are purines
Adenine
Guanine
What does Cytosine pair with
Guanine
What does adenine pair with
Thymine
What is the structure of DNA called?
Double helix
What are the 2 types of bond in a stand of DNA
Carbon bond (middle of the ladder)
Convalent bond
How can DNA unzip during protein synthesis?
Because the hydrogen bonds are much weaker than the covalent bonds
How many strands of nucleotides does RNA have?
1
What is the name of the sugar RNA is made from?
Ribose
What is the name of the process when messenger RNA copies a recipe from DNA
Transcription
What is the name for when the ribosome produces a protein
Translation
Examples of proteins in the body
Muscle tissue and enzymes
What is DNA condensed to form?
Chromosomes
What are the end sections of dna called?
Telomeres
What are telomeres?
End sections of dna
What shortens telomeres?
Aging
Stress
Poor nutrition
Negative thoughts
Herb that’s been shown to reduce telomere shortening
Gotu kola
What is a mutation?
Change in dna sequence
What can a dna mutation cause?
Change in the sequence of amino acids in the protein which can impact shape and function
What happens to dna in sickle cell anaemia
Proteins in haemoglobin become abnormally shaped
How is haemophilia linked to gene expression?
Mutations in genes linked to clotting factors 8 and 9
What is the link between cancer and gene mutations?
Mutations occur due to factors such as radiation, medications, stress and chemicals
Which genes do cancer genetic mutations impact?
Genes that code for proteins involved in regulating cell division
What is gene expression
Whether we copy the gene and make the protein or not
Which can we change? Our genes or our gene expression
Gene expression - whether we copy the gene or not
Nutrients that influence if a gene is copied
Vitamin A
Vitamin D
Essential fatty acids
Zinc
Fibre
How can fibre impact gene expression
By affecting hormone levels and the metabolites created when intestinal floral feed on fibre
What environment do we bathe our genes in that can promote cancer?
Acid
Glucose rich
Anaerobic
Environment that can inhibit healthy gene expression
Lack of oxygen
Stress
Drugs
Why might someone eating lots of beta carotene rich foods be deficient in vitamin A
Could be genetics