SAC 1 Flashcards
Plasma membranes, proteins, enzymes and energy transformations.
Unicellular
Consisting of one cell
Multicellular
Composed of many cells
Autotrophs
Manufacture their own food
Heterotrophs
Rely on other sources for food
Organic chemicals
Complex carbon-containing molecules
Inorganic molecules
Do not contain carbon in a complex form Eg water co2 o2 minerals such as cl-, k+, mg2+
Ionic bonds
Occur between ions, particles that have an electrical charge
Pos and neg charges attract
Eg Na+ are attracted to Cl- to form NaCl
Covalent Bonds
Bonds in which atoms share electrons
Polar or non polar
H20 is polar
Ch4 (methane) is non polar
Hydrogen bonds
formed by the attraction between polar molecules
Not very strong
Eg liquid water is held together by hydrogen bonds between H and O atoms in water molecules
Biomacromolecules
Proteins
Carbohydrates
Nucleic Acids
Lipids
What are polymers made up of?
Many monomers
Why are lipids different?
They rarely form polymers
Condensation reaction
Water is released
Building larger molecules
Forming polymers
Prokaryotic cells
smallest living cells diameters of 0.5 to 1.0 micrometres have a cell membrane and cytosol lack membrane bound organelles have no nuclear membrane have just one circular chromosome
Plasmids
small circular units of DNA
Fimbriae
hairline structures used for attachment
cell wall in a prokaryote
made of a polysaccharide
capsule
protects bacteria
flagellum
used for movement
Simple base molecule of carbohydrates
monosaccharides
Simple base molecule of proteins
amino acids
Simple base molecule of nucleic acids
nucleotides
Simple base molecule of lipids
fatty acid
steroids
Carbohydrates
carbon hydrogen oxygen important as an energy supply some are important in structural support
Proteins
carbon hydrogen oxygen nitrogen some contain sulfur
nucleic acids
carbon hydrogen oxygen nitrogen phosphorous DNA or RNA
DNA stands for
deoxyribonucleic acid
RNA stands for
ribonucleic acid
Lipids
carbon hydrogen oxygen may contain phosphorous and nitrogen insoluble in water (hydrophobic) do not form polymers
monosaccharides
most important of which is glucose
others include fructose, galactose and ribose
monosaccharides contain rings of carbon atoms bonded covalently to oxygen and hydrogen atoms
amino acids
20 commonly found in proteins
contain and amino group (NH2) and a carboxylic acid group (COOH)
Basic structure is the same, R group varies in each of the 20 amino acids
nucleotides
nitrogenous base
phosphate group and 6-C sugar (deoxyribose or ribose) alternating backbone
Starch
branched chains of glucose molecules used as a storage molecule in plants
glycogen
branched chains of glucose molecules used as a storage molecule in animals
the chains are more branched than those in starch
cellulose
also composed of glucose molecules
it forms plant cell walls
chitin
forms the basis of insect exoskeletons, and the cell walls of some fungi.
composed of chains of modified glucose molecules
peptides and polypeptides
chains of amino acids
individual amino acids are held together by peptide bonds
protein
is one or more polypeptides coiled or folded into a specific shape