54 terms

SL Chemistry of life

What are the four types of organic molecules found in living organisms?
Carbohydrates, lipids, proteins, nucleic acids
What are the four most common elements found in living things?
Carbon, Hydrogen, Oxygen, and Nitrogen (CHON)
What is the role of Sulfur in plants, animals, and eukaryotes?
In some amino acids
What is the role of calcium in plants?
Co-factor in some enzymes,
What is the role of calcium in animals?
co-factor in some enzymes and composition of bones
What is the role of calcium in some enzymes?
co-factor in some enzymes
What is the role of phosphorus in plants, animals, and prokaryotes?
Phosphate groups in ATP
What are carbohydrates composed of and what is their function?
CHO - serve as main energy source
What are lipids composed of and what is their function?
CHO - store energy
What are proteins composed of and what is their function?
CHON - code for DNA/RNA, form bones and muscle, enzymes, hemoglobin, antibodies
What is the role of iron in plants and prokaryotes?
They are in the cytochromes
What is the role of iron in animals?
They are in the cytochromes and in hemoglobin
What is the role of sodium in plants, animals, and prokaryotes?
In membrane function
What are polar covalent bonds?
Polar covalent bonds are the bonds formed between hydrogen and oxygen atoms within water molecules. They result in slightly positive Hydrogen atoms and slightly negative oxygen atom.
What is high specific heat?
The ability to absorb and give off heat without changing temperature
What is high heat of vaporization?
The ability to absorb heat upon evaporation - it is used as a cooling mechanism
What are the solvent properties of water?
Water is the universal solvent, therefore much of the biochemistry in a cell occurs in water. (blood)
What are the five components that make up blood?
Red Blood Cells, White Blood Cells, Water, Platelets, misc. solutes
What are four common solutes found in blood plasma?
glucose, amino acids, fibrinogen, and hydrogencarbonate
What does it mean to be organic?
living organisms with carbon
What are the different sizes of carbohydrates?
monosaccharides, disaccharides, polysaccharides
What is glucose used for, and what size carbohydrate is it?
monosaccharide - chemical fuel for respiration
What is fructose used for, and what size carbohydrate is it?
sweetening in fruit, monosaccharide
What is lactose used for and what size carb is it?
makes up solutes in milk, disaccharide
What is sucrose used for and what size carbohydrate is it?
disaccharide - transported from leaves of plants to other locations in the plant by vascular tissue
What is glycogen?
Polysaccharide; stores glucose in liver and muscles, used by animals
What is starch?
Polysaccharide - stores glucose for plants,
What are cellulose & chitin?
Polysaccharide Carbohydrate - important for structure
What are the three functions of lipids?
energy storage, thermal insulation, buoyancy
What are triglycerides?
Form of lipid, solids are fats, liquids are oils
What are the subcomponents of proteins?
amino acids
What is the primary structure of a protein?
linear sequence of amino acids joined by peptide linkages
What is the secondary structure of a protein?
forms structural proteins - helix and pleated sheets
What is the tertiary structure of a protein?
Folded polypeptide chains into specific shapes - globular
What is the quaternary structure of a protein?
two or more polypeptide chains joined
What are the characteristics of fibrous proteins?
Chain extended, Insoluble, Resistance to pH/temperature changes, Structural material
What are the characteristics of globular proteins?
Chain folded, soluble, colloidal, susceptible to pH/temperature changes, compact rounded molecules
What are the subcomponents of nucleic acids?
How does ingestion work?
Food is chemically digested in alimentary canal by hydrolysing enzymes and requires water as a reactant
What are the advantages of carbohydrates as storage mechanisms?
more easily digested and soluble in water
What are the advantages of lipids as storage mechanisms?
Contain more energy per gram, insoluble in water (doesn't interfere with osmosis)
Through which process are monosaccharides connected to form disaccharides?
Condensation - requires water
What is hydrolysis?
The process by which disaccharides can be broken down into monosaccharides
What are nucleotides?
subcomponent of DNA that contains: a phosphate group, a sugar (deoxyribose), and a nitrogenous base
What are nitrogenous bases?
Adenine, Guanine, Thymine, Cytosine
How are DNA molecules structured?
a double helix, with each strand being shaped like a ladder.
What must the environment be like for replication to occur?
Nucleus during interphase, DNA is in chromatin, Helicase & polymerase are present in nucleoplasm, Free nucleotides are present in nucleoplasm
What happens during replication?
1. Helicase separates the double helix into two single strands by breaking the hydrogen bonds between nitrogen bases

2. Nucleotides in the cytoplasm begin to attach to the "unzipped" double helix - the first nucleotide attaches, then the second nucleotide that follows it becomes covalently bonded to the first by the enzymes polymerase - forming a new strand (1/2 the double helix)
What happens during transcription?
1. Helicase unzips one part of the DNA where the gene that needs to be copied is located, 2. RNA polymerase moves along one side of the DNA, attaching free RNA nucleotides to it. Only one side is used, 3. The mRNA will detach from the DNA after being transcribed and float free in nucleoplasm until floating out of holes in nuclear membrane
What happens during Translation?
1. mRNA aligns with a ribosome, so that first two codons are within the ribosome.

2. Corresponding tRNA will attach to the mRNA in the ribosome.

3. An enzyme creates a peptide bond between the amino acids of the tRNA in the ribosome.

4. the mRNA moves through the ribosome repeating this whole process until it is done
What are enzymes?
proteins with a specific 3D shape that contains an active site that perfectly fits a substrate.
What factors affect enzyme-catalysed reactions?
Temperature - faster particle collision, but maxes out at the point at which the enzyme loses its shape
⁃ pH
⁃ substrate concentration - more substrates means a higher chance of pairing with an active site, yet this will plateau at the point in which an enzyme is at its maximum working power
What is rapid oxidation?
release of chemical energy not controlled by enzymes, uncontrolled energy release (burning)
What is slow oxidation?
cells metabolize (break down) nutrients by oxidizing bonds (breaking) one at a time as they are acted upon by a series of enzymes.
⁃ the ultimate goal is to produce ATP
⁃ Uses glucose, but can substitute fatty acids/amino acids