Unit 1 Flashcards
What are the biological atoms?
Sulfur, Phosphorus, Oxygen, Nitrogen, Carbon and Hydrogen
What is a macro-molecule?
a large complex structure
What is a polymer?
chain of repeating smaller subunits linked by covalent bonds
What are the 4 types of macro-molecules?
Proteins, Carbohydrates, Lipids, Nucleic Acids
What is a carbohydrate?
biological macromolecule that always has carbon, hydrogen and oxygen in a 1:2:1 ratio. Also has a high number of hydroxyl groups to allow for energy storage
What is starch used for?
short term energy storage in plants
What is glycogen used for?
short term energy in animals and an be broken down for energy faster than starch
What is cellulose used for?
provides structural support in plants
What is a lipid?
biological macromolecule with high proportions of non-polar CH bonds and they are hydrophobic whch plays a key role in determining their function
Why are lipids good for long term energy storage? Why not?
they have many CH bonds which can store energy longer but they are also less accessible so are used after carbohydrates.
How are lipids used in humans?
insulation, protection for major organs, in cell membranes
What are the main structural features of a carbohydrate?
- lots of OH (hydroxyl) groups
- carbon, hydrogen and oxygen occur in 1:2:1 ratio
What are the main structural features of a lipid?
- have long tails with many carbons
- have ester bond and a double bonded oxygen
- has a head and tail ends (usually)
What is a triglyceride?
lipid molecule made of glycerol molecule and 3 fatty acids linked by ester bonds
What is a fatty acid?
a hydrocarbon chain ending in a carboxyl group (COOH)
- can be saturated (all single bonds) or unsaturated (1+ double bonds)
What is monounsaturated?
one double bond
What is polyunstaurated?
2 or more double bonds. Humans cannot sythesize this so it is necessary in our diets.
What is a phospholipid?
composed of a glycerol molecule bonded to 2 fatty acids and a phosphate group with an R group.
What are phospholipids commonly found in?
they make up the cell membrane
What is so important about the head and the tail of a phospholipid?
the head is polar and hydrophillic and the tail is non-polar and hydrophobic. This is important in forming the phospholipid bilayer.
What is the phospholipid bilayer?
structure with heads of phospholipid toward aqueous envirronment in cells cytoplasm and extracellular fluid and tails toward centre interacting with each other
What are some other lipids?
Cholesterol, Steroids, Waxes
What is a protein?
has an amino group and carboxyl functional group and an R group that determines the amino acid
What are the main structural features of a protein?
- amino group (look for the nitrogen)
- has an R group
- has a carboxyl group (carbon with both a double bonded oxygen and hydroxyl group)
What are the 6 functions of proteins?
- catalyze chemical reactions
- structural support
- Transportation
- Movement (muscle tissue)
- Regulation (hormones)
- Disease Defence (anitbodies made by immune system)
What is the general structure of a protein?
- long chains of amino acids
- unique sequence of amino aacids
What are the 4 levels of protein organization?
- Primary
- Secondary
- Tertiary
- Quaternary
What is denaturation?
conformational change to a protein that can cause permenant or temporary changes and may cause the protein to lose its functional ability under certain circumstances
What are the conditions for denaturation?
Temperature, pH and ionic concentrations
What is a nucleic acid?
organic compound that carries hereditary information in cells and is composed of nucleotide monomers
What are the main structural features of a nucleic acid?
- has phosphodiester bonds
- has backbone made of alternating sugar-phosphate-sugar-phosphate chains
- middle is made of nitrogenous bases held by hydrogen bonds
What are the 4 types of biochemical reactions?
neutralization, redox, condensation/dehydration synthesis, hydrolysis
What Dehydration Synthesis?
joins monomers together to create polymers, H+OH= water. WATER IS A PRODUCT
What is Hydrolysis?
breaks down polymers into monomers with addition of water. Hydrogen goes to one monomer and hydroxyl group goes to the other WATER IS A REACTANT
What is an enzyme?
biological catalyst that speeds up reactions by decreasing activation energy. Usually end in “ase”
What is activation energy?
the energy required to break bonds
What is a substrate?
the molecule which is catalyzed by an enzyme. It attaches to the enzyme at the active site
What is the active site?
where substrate binds and shape is a perfect match
What is the enzyme-substrate complex?
when the substrate and the enzyme come together
What is the induced fit model?
as a substrate approaches an active site, interactions between functional groups causes the protein to alter its shape to fit the substrate
What is a coenzyme?
organic, assists enzymes, ex. vitamins
What is a cofactor?
mineral or metal ions ex. iron, zinc, sodium
What are the factors that affect enzyme activity?
Temperature and pH level
How does temperature affect enzyme activity?
there is an optimum range that is relative to the organisms environment where certain enzymes can work and when they cannot
How does pH affect enzyme activity?
there is an optimum range where enzymes work best at specific pH levels. Ex. pepsin in the stomach only wors at a pH of 2
What 2 ways can you regulate enzyme activity?
Activators- increase activity
Inhibitors- decrease activity
Why do you regulate enzyme activity?
to control biochemical pathways
What are the 2 types of inhibition?
Competitive and Non-Competitive
What is competitive inhibition?
inhibitor bonds at active site therefore restricting access for normal substrate
What is non-competitive inhibition?
inhibitor binds to allosteric site and causes the shape of the active site ti change therefore the substrate cannot bind to the active site.
What is the allosteric site?
a different location than the active site on an enzyme where other molecules or non-competitive inhibitors can bind
What is feedback inhibition?
where the end product of a biochemical pathway increases and causes end product t “feedback” to allosterically inhibit a substrate at the beginning of the pathway
