White blood cells make up approximately 1% of the total blood volume in a healthy adult, making them substantially less numerous than the red blood cells at 40% to 45%.
Robert Hooke looked through a primitive microscope at a thinly cut piece of cork. He saw a series of walled boxes that reminded him of the tiny rooms, or cellula, occupied by monks.
All organisms are composed of one or more cells. The cell is the basic unit of structure and organization in organisms. All cells come from pre-existing cells. And Anton Van Leeuwenhoek made his version of the microscope and discovered something very odd when he looked a the gunk on his teeth.
Plant cells are a form of eukaryotic cells with true nucleus and organelles. Various types of plant cells are -xylem cells, phloem cells ,parenchyma cells, collenchyma cells and sclerenchyma cells. These cells distinguish plants from animal kingdoms.
In desert plants like cactus, they have an exquisite set of adaptations for optimal water management. They have thickened stem tissues with thin-walled parenchyma cells so a lot of water can be stored in stems.
The ocean acts as a neutralizer to the carbon cycle. The ocean absorbs most of the excess co2.