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Biology
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Describe the role of haemoglobin in supplying oxygen to the tissues of the body?

Haemoglobin is an oxygen carrying molecule found in red blood cells. Haemoglobin is made up of four polpeptide chains (2 alpha, 2 beta), and consists of four haem groups (iron associated with heam) contai...

OB
Answered by Olivia B. Biology tutor
14973 Views

7 Albinism is a genetic trait resulting from the inheritance of recessive alleles. (a) (i) Distinguish between the terms allele and gene. (ii) Explain the meaning of the term recessive allele.

a i) a gene is a section of DNA that codes for a protein and has a specific location on a chromosome while an ellel is just a different form of a gene

ii) a recessive allele is one that is expresse...

EI
Answered by Elysa I. Biology tutor
5186 Views

Why do myelinated axons propagate action potentials faster than unmyelinated axons?

Unlike unmyelinated axons, myelinated axons are surrounded by an insulatory myelin sheath produced by Schwann cells. Because of this insulatory sheath, action potentials cannot occur along the entire leng...

TD
32866 Views

Describe the hormone changes which lead to ovulation.

Follicle stimulating hormone (FSH) secreted from the pituitary gland stimulates egg maturation and oestrogen secretion from the ovaries. Oestrogen in turn inhibits FSH release and stimulates luteinising h...

TD
4207 Views

How does vaccination lead to immunity?

Vaccination involves administering a dead or inactive form of a pathogen to a subject, which stimulates white blood cells into producing antibodies specific for that pathogen. If the subject encounters th...

TD
3039 Views

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