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Biology

A Level

Describe the structure of the cell membrane.

The cell membrane is a fluid matrix made of a phospholipid bilayer. Each lipid molecule has a hydrophilic, phosphorylated "head" and a hydrophobic, fatty acid "tail". The hydrophob...

Answered by Srishti N. • Biology tutor

42766 Views

What's the difference between genotype and phenotype?

The genotype of an organism is the alleles it has. while the phenotype is the characteristics the alleles produce.

For examples the alleles for hair colour could be BB for brown hair...

Answered by Lauren G. • Biology tutor

10257 Views

What are gene mutations?

A mutation is any change to the base sequence of DNA.

The different types of mutations that can occur include:

Subsitution - this is where one base is swapped for another

Delet...

Answered by Lauren G. • Biology tutor

5766 Views

What is endosymbiosis and how does it relate to mitochondria?

Endosymbiosis is where two organisms live together, one inside the other: endo=in, sym=together and biosis=living.

Answered by Aidan H. • Biology tutor

5183 Views

Describe the structure of the cell membrane

The cell membrane is made up of something called the phospholipid bilayer. This is exactly what it sounds like:a hydrophilic phosphate head on the outside and a hydrophobic lipid on the inside.

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Answered by Thomas W. • Biology tutor

5859 Views