How would you recognise red blood cells when looking at a colour photograph of blood taken with a light microscope?

Erythrocytes, or red blood cells, are by far the predominant cell type in the blood smear. They appear as biconcave discs of uniform shape and size (7.2 microns) that lack organelles and granules. Red blood cells have a characteristic pink appearance due to their high content of haemoglobin.

carbohydrates: (starches and sugars) composed of carbon, hydrogen, and oxygen.

lipids: (fats, oils, and waxes) are made of carbon and hydrogen atoms.

nucleic acids: contain hydrogen, oxygen, nitrogen, carbon, and phosphorus. they are polymers of nucleotides. a nucleotide has three parts, a 5-carbon sugar, a phosphate     (-po⬇️4) group, and a nitrogenous base.

proteins: made up of nitrogen, carbon, hydrogen, and oxygen. they are polymers of amino acids.