biochemistry Flashcards
Why are lipids not true polymers?
They don’t have repeating subunits (monomers)
What elements are found in all proteins?
Carbon, hydrogen, oxygen, nitrogen
What is the monomer of proteins?
Amino acids
What are the common parts of amino acids?
Amine group, carboxyl group, hydrogen atom, R group, central carbon
What takes place to form a protein polymer?
Dehydration synthesis
How do amino acids differ from one another?
By their different R groups
What is the function of defensive proteins?
Identifying/killing disease-causing organisms or particles, e.g., antibodies combat bacteria/viruses
What is the function of motor proteins?
Contractile, helps muscles, e.g., muscles mode of action in myosin
What is the function of enzymatic proteins?
Speed up chemical reactions, biological catalysts, ex: digestive enzymes- hydrolysis polymers
What is the function of peptide hormones?
Chemical messengers to coordinate functions, e.g., insulin helps regulate sugar concentration in blood
What is the function of structural proteins?
Provides physical support and protection, e.g., collagen, elastin in animal connective tissue, keratin in hair
What is the function of transport proteins?
Carry substances in the body/membrane, e.g., hemoglobin transports oxygen through blood
What is the function of storage proteins?
Allow organisms to store amino acids as ‘food’ for developing embryos, e.g., egg whites for developing chicks
How is one protein different from another?
Variations in the sequence of amino acids, their structure determines functions
How do proteins form their unique 3D shapes?
Through tertiary structure
What is the primary structure of proteins?
Sequence of amino acids, determines shape and function
What is the secondary structure of proteins?
Alpha helix winds up, beta pleated sheets fold, held by hydrogen bonds
What is the tertiary structure of proteins?
Helix or beta pleated sheets wrap around themselves to create a 3D globular shape
What is the quaternary structure of proteins?
Makes a very large protein, 2 or more tertiary proteins wrapped together
What does unfolding proteins lead to?
Denaturing the protein, destroys shape
What is denaturing and what causes it?
The process where proteins lose their original structure and function, often caused by changes in temperature, pH, or chemicals
How do primary, secondary, tertiary, and quaternary structures denature?
Primary: disruption of peptide bonds, Secondary: disruption of hydrogen bonds, Tertiary: disruption of various bonds, Quaternary: disruption of interchain interactions
What is the difference between DNA and RNA?
Different nitrogenous bases (DNA: thymine, RNA: uracil), double stranded vs single stranded, genetic info vs protein synthesis
What is this and why? (Image of DNA)
DNA because it has thymine in nitrogenous base and is double stranded
What is this and why? (Image of polypeptide chain)
Polypeptide chain, sequence of many amino acids
What is this and why? (Image of dipeptide)
Dipeptide, because of the peptide bonds between 2 amino acids
Where are proteins found in food?
In meats and animal products
What are the elements of nucleic acids?
Carbon, hydrogen, oxygen, nitrogen, phosphorus
What are nucleic acid monomers and their parts?
Nucleotides: phosphate group, nitrogenous base, sugar
How do nucleic acid monomers differ?
By different nitrogenous bases or sugars, DNA has thymine, RNA has uracil
What is the function of DNA?
Stores information for putting amino acids together to make proteins, basis of genes and heredity
What is the function of RNA?
Helps build proteins, carries genetic info
What is this and why? (Image of nucleotide)
Nucleotide, contains all 3 parts
What is ATP and its function?
Main form of energy cells use, provides energy for biological processes
What are the 2 main reasons we eat?
To obtain energy and provide essential nutrients for bodily functions
What is the difference between the energy in carbs, lipids, and proteins?
Lipids have the highest energy content and provide more than double the energy than carbs and proteins per gram
Why do we eat carbs?
For immediate energy
Why do we eat lipids?
For long-term energy storage and cell structure
Why do we eat proteins?
For tissue repair and growth
Is ATP found in food we eat?
No, it is produced from nutrients found in food that are broken down via hydrolysis
What is the difference between Calorie and calorie?
Calorie = kilocalorie = 1000 calories; calorie = amount of energy required to raise 1g of water 1 degree Celsius
How do you find calories in calorimetry?
(mass of water)(final temp – initial temp, degrees Celsius)
How many calories if there is 25 mL of water, final: 69 degrees Celsius, initial: 15 degrees Celsius, 0.4 mass burned?
1350 cal, 3375 cal per gram, 3.375 kilocal per gram
What is the function of enzymes in chemical reactions?
Has an active site that binds substrates to be acted on
What is the difference between anabolism and catabolism?
Anabolism: bringing substrates together to form a byproduct; Catabolism: breaking down substrates into products
Does the shape of an enzyme change in a reaction?
No
How do environmental changes affect enzymes?
Can alter the temperature or pH, potentially leading to denaturation
What is enzyme specificity?
The reaction catalyzed by an enzyme is very specific, determining the shape and features of the active site and substrates
What is induced fit?
When an enzyme changes shape to better fit a substrate upon binding
What is the purpose of enzymes?
To catalyze/speed up reactions in living things that could occur without an enzyme, but would take a very long time
What type of macromolecule is an enzyme?
Proteins
Polymers are (what size of mol)
large molecules
