The eye is a complex sensory organ that allows us to see the world around us. The eye works by gathering light from the environment and converting it into electrical signals that can be interpreted by the brain. The basic structure of the eye includes the cornea, iris, pupil, lens, retina, and optic nerve. The cornea is the transparent outer layer of the eye that helps to focus incoming light. The iris is the colored part of the eye that regulates the amount of light that enters the eye through the pupil, which is the black circular opening in the center of the iris. The lens is a clear, flexible structure located behind the iris that helps to focus light onto the retina. The retina is a thin layer of tissue that lines the back of the eye and contains photoreceptor cells called rods and cones. These cells convert light into electrical signals that are sent to the brain via the optic nerve. The rods are responsible for the low light vision and detecting motion, while the cones are resp
Algae term was given by Linnaeus. The study of algae is called Phycology and the father of phycology is Fristch. He wrote a book Structure and reproduction of algae. The father of Indian phycology is M.O.P. Iyengar. Algae are multicellular eukaryotic organisms placed in the kingdom Plantae. They are autotrophic i.e. they manufacture their food by photosynthesis. They are found in both fresh and marine water and in many forms like filamentous, colonial. Algae are surrounded by mucilagenous sheath and below the sheath cell wall is present which is made up of cellulose and pectin but mainly made up of cellulose, galactans, mannans and mineral-like calcium carbonate. On the basis of structure, they are thalloid i.e. plant body is not differentiated into root, stem and leaves. The tissue system is also absent in algae. On the basis of nutrition, they are photoautotrophic.They have chloroplast in which photosynthetic pigments are present. classification of algae is mainly based on pigments