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What are the functions of the cell membrane?

The cell membrane separates the intracellular and extracellular environments. The lipid bilayer only allows small polar molecules (such as O2 or CO2), small hydrophobic molecules (fatty acids, steroid hor...

Answered by Francesca D. • Biology tutor

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How can bacteria become resistant to antibiotics and how can doctors reduce the number of bacteria that become resistant?

-A mutation in a pathogen may produce a new strain. This new strain may become resistant to an antibiotic through natural selection. The new strain ma...

Answered by Helen C. • Biology tutor

14668 Views

Using the Hardy Weinberg principle, calculate the frequency of the heterozygous genotype in the population if the frequency of the dominant allele p is 0.864. Express your answer as a percentage of the population.

p²+ 2pq + q²= 1.0

p + q = 1.0

1.0 - p = q

1.0 - 0.864 = 0.136

q = 0.136

...

Answered by Helen C. • Biology tutor

7447 Views

Explain the difference between spatial and temporal summation at a synapse.

-Spatial summation occurs when multiple presynaptic neurones together release enough neurotransmitter (e.g. acetylcholine) to exceed the threshold of the postsynaptic neurone. For exam...

Answered by Helen C. • Biology tutor

181881 Views

Differentiate between sense and antisense codons?

Sence codons are used for synthesizing mRNA and are generated as complementary strand during DNA semi-conservative replication while Antisense codons are the template used for DNA replication and can't...

Answered by HAMMED B. • Biology tutor

13613 Views