Top answers

Biology
A Level

Name and describe the 4 steps involved in aerobic respiration

Glycolysis- This is the first step which occurs in the cytosol. glucose broken down into pyruvate yielding 2 net atp and 2 pyruvate molecules per glucose. This is the only step in anaerobic respiration. <...

UO
Answered by Uchenna O. Biology tutor
4855 Views

Give 3 differences in structure between DNA and mRNA

DNA contains the nucleotide base thymine whereas mRNA contains the nucleotide base uracil instead

DNA is double stranded, mRNA is single stranded

DNA contains the sugar subunit deoxyribose, ...

CB
Answered by Callum B. Biology tutor
10631 Views

What does the DNA sequence being 'degenerate' mean?

Amino acids are coded for by specific codons. There are some instances where some particular amino acids can be coded for by more than one codon (codon being three nucleotides bonded together). This is kn...

BN
Answered by Bibi N. Biology tutor
12339 Views

Describe and explain the effects of pH, temperature, enzyme concentration and substrate concentration on enzyme activity

pH: All enzymes have an optimum pH value which is very specific. This is because hydrogen ions and hydroxide ions have very significant changes on the tertiary structure of an enzyme, whi...

EO
Answered by Eloise O. Biology tutor
16512 Views

Putting bee honey on a cut kills bacteria. Honey contains a high concentration of sugar. Use your knowledge of water potential to suggest how putting honey on a cut kills bacteria.

Once honey is added to an infected cut, the osmotic gradient favours water moving from the bacterial cells to the honey. This is because the water potential is lower in the honey. As a result of the loss ...

HM
Answered by Harry M. Biology tutor
3820 Views

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