In the bones and in their arrangement there is a close resemblance in the two cases, yet the outcome is very different. The multiplication of finger joints in the whale is a striking feature.
An atom is the smallest particle of a chemical element. Two or more atoms come together to form a molecule: thus molecules form the mass of matter. A molecule of water is made up of two atoms of hydrogen and one atom of oxygen. Molecules of different substances, therefore, are of different sizes according to the number and kind of the particular atoms of which they are composed. A starch molecule contains no less than 25,000 atoms.
Molecules, of course, are invisible. The above diagram illustrates the comparative sizes of molecules.
A. Fore-limb of Monkey B. Fore-limb of Whale
What is meant by homology? Essential similarity of architecture, though the appearances may be very different
This is seen in comparing these two fore-limbs, A, of Monkey, B, of Whale. They are as different as possible, yet they show the same bones, e.g. SC, the scapula or shoulder-blade; H, the humerus or upper arm; R and U, the radius and ulna of the fore-arm; CA, the wrist; MC, the palm; and then the fingers.
Two gentlemen talking
Man with long beard
Man cleaning his glasses with a handkerchief
Bartender looking at beer
Man in pub having a beer
Unhappy man with cigar
Pleased to meet you, man showing respect when greeting someone
European man with hat in hand shrugging
Man looking up from his reading and smiling
Man looking at the money in his hand
Man reading on stage
Man on the stage
Man smiling and rubbing his hands
Man smoking a cigar
Man standing in a patronizing stance
Man carrying a top hat
Man wringing his hands in anticipation of making some money