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What is the principal component of hair and nails
A. collagen
B. melanin
C. elastin
D. keratin
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The Brain › ViewThe center of visual perception
A. Frontal lobe
B. Parietal lobe
C. Occipital lobe
D. Temporal lobe
Genes, Chromosomes and Genome › View
Which of the following correctly summarises the distinction between an organism’s genotype and their phenotype?
A. genotype refers to the alleles that an organism has inherited for a particular gene, while phenotype refers to all of an organism’s observable traits
B. genotype refers to any observable characteristics arising from an organism’s genome, while phenotype refers to the expression of traits based on the environment