There are many ways in which living organisms differ from each other. In this essay I will discuss the various ways of which this occurs.
There are two different types of cells, there are prokaryotes and eukaryotes. Within eukaryotes there are different structures and similar structures. For example; in a plant cell they have a nucleus, mitochondria an ER, and a Golgi body. These are the same as animal cells; however they differ because plants cells have a cellulose cell wall, chloroplasts, large central vacuole and they use starch for storage whereas an animal cell has lysosomes, rough ER, smooth ER and ribosomes. Eukaryotes differ from prokaryotes because prokaryotes have no nucleus, they just have a loop of DNA and they also have no membrane-bound organelles. Prokaryotes also have a cell wall, along with a slime capsule, flagellae and plasmids.
Another way of which living organisms differ from each other is through proteins. Proteins are made up of amino acids and they condense together to form a dipeptide. Polypeptides are many amino acids bonded together through a peptide bond. The primary structure is the sequence of amino acids in a polypeptide. Each organism has a different sequence of amino acids which make up their base sequence and consequently code their genetics.
DNA consists of two polynucleotide chains and these nucleotides consist of a deoxyribose sugar, a nitrogenous base and a phosphate group. The bases are Adenine, Cytosine, Guanine and Thymine. The sequence of these bases on DNA determines the structure of these proteins. A gene is a sequence of bases which codes for a single polypeptide. Chromosomes carry these genes and these genes come in specific forms called an allele which is how living organisms vary from each other. For example, humans are made up of an XY or XX chromosome. Females are XX and males are XY, however in some animals their sex is determined by the ZW sex-determination