Triple Biology Test - DNA, enzymes, respiration, protein synthesis

What are the correct base pairings in DNA?

Tick all that apply about DNA.

Each base in [blank_start]DNA[blank_end] forms [blank_start]cross[blank_end] links with their [blank_start]complementary[blank_end] pairs on the other strand, keeping the strands [blank_start]tightly[blank_end] wound together. Complementary pairing also allows and helps [blank_start]protein[blank_end] synthesis.

Protein synthesis takes place in the [blank_start]cytoplasm[blank_end] and is aided by the [blank_start]ribosomes[blank_end]. The order of bases in a gene code for a different order of amino acids in a protein. Each amino acid is coded for by a sequence of [blank_start]three[blank_end] bases called a [blank_start]triplet[blank_end] code. A [blank_start]shorter[blank_end], single strand of DNA (called mRNA) goes through the unzipped DNA and matches each base with their [blank_start]complementary[blank_end] pair. This is called [blank_start]transcription[blank_end]. The mRNA leaves the nucleus and enters the cytoplasm, where the [blank_start]ribosomes[blank_end] read the [blank_start]triplet[blank_end] codes and form the correct sequence of amino acids, joining them together to make a [blank_start]protein[blank_end].

Enzymes are [blank_start]biological[blank_end] catalysts. They help to speed up reactions without [blank_start]damaging[blank_end] themselves or getting 'used up'. Enzymes are [blank_start]proteins[blank_end] and are [blank_start]very[blank_end] specific. The [blank_start]lock[blank_end] and key method means the substrate can only enter the active site of the enzyme that has been built to break down that substrate. Carbohydrase (example: [blank_start]amylase[blank_end]) break down carbohydrates into [blank_start]starch[blank_end] and simple sugars. Protease (example: [blank_start]pepsin[blank_end]) break down proteins into amino acids. Lipase (example: [blank_start]lipids[blank_end]) break down [blank_start]fats[blank_end] and oils into fatty acids and [blank_start]glycerol[blank_end].

Enzymes all have optimum pHs, temperatures and [blank_start]concentrations[blank_end]. The optimum means the enzyme is working at its [blank_start]highest[blank_end] possible efficiency. Too high or too low of a pH effects the [blank_start]bonds[blank_end] between enzymes and substrates, slowing the rate of reaction. If an enzyme concentration is increased, eventually the rate of reaction will remain the [blank_start]same[blank_end] as all the [blank_start]substrates[blank_end] have been broken down. If the substrate concentration is increased, eventually the rate of reaction will remain the [blank_start]same[blank_end] as all the active sites are [blank_start]full[blank_end].

Match the chemical with what they test for and how it is shown. Ethanol tests for [blank_start]fats[blank_end]. It has a [blank_start]creamy precipitate[blank_end] if it is present and clear if it is not. Iodine tests for [blank_start]starch[blank_end]. It is [blank_start]black / purple[blank_end] when it is present and [blank_start]yellow[blank_end] if it is not. Benedict's solution tests for [blank_start]reducing sugars[blank_end]. It is [blank_start]red[blank_end] if it is present and [blank_start]blue[blank_end] if it is not. Buiret solution tests for [blank_start]protein[blank_end]. It is [blank_start]pink[blank_end] if it is present and blue if it is not.

Respiration is the process of [blank_start]transferring[blank_end] energy from the break down of sugar. The energy transferred [blank_start]can't[blank_end] be used directly by the cells, so it is used to make [blank_start]ATP[blank_end]. [blank_start]Aerobic[blank_end] respiration happens when there is plenty of oxygen available. Glucose + oxygen -----> carbon dioxide + [blank_start]water[blank_end] + energy [blank_start]Anaerobic[blank_end] respiration produces less [blank_start]energy[blank_end]. Glucose is broken down to make [blank_start]lactic[blank_end] acid (in animals) or [blank_start]ethanol[blank_end], carbon dioxide and energy (in [blank_start]yeast[blank_end] and fungi).