Evolution: Natural SelectionNatural SelectionEvolution, the change of species over time, is the central unifying theme of biology. Biological evolution occurs through natural selection. Natural selection is the result of overproduction of offspring havi…

Skeletal, Muscular and Integumentary SystemsSkeletal SystemYour skeletal system isn’t just your bones; it’s your bone marrow, cartilage, and ligaments all make up this important body system.As an embryo, you are made up almost completely of cartilage. Ca…

Laboratory Skills: Scientific MethodVocabulary: bias, conclusion, control, control group, data, dependent variable, experimental design, experimental group, hypothesis, independent variable, peer feedback, peer review, problem, results, scientific metho…

PopulationsVocabulary: ecology, population, community, ecosystem, biosphere, cycling, biodiversity, habitat, nicheCarrying CapacityCarrying capacity is the maximum number of organisms the resources of an ecosystem can support. The carrying capacity of th…

Respiration In Plants By young roots: Air occurs in soil interspaces. Root hairs as well as epiblema cells of the young roots are in contact with them. They are also permeable to metabolic gases. Oxygen of the soil air diffuses through root hair-epiblema…

Mammalian Respiratory System The mammalian respiratory system consists of nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles and alveoli. Nostril: It is also called external nares. Nasal Chamber: Nasal septum divides nasal cavity into two nasa…

What Is NutritionOrganisms need energy to live and grow. This energy is obtained from food. Any substance that can be broken down by chemical processes in the body of an organism to give energy is called food. The process of intaking the food & utili…

Nutrition in AmoebaNutrition in Amoeba: Protozoan protests carry out holozoic nutrition through intracellular digestion. (i) Ingestion: Some protests can ingest food particle from any point on the surface (e.g., Amoeba) while others have fixed points for…

Nutrition In PlantsPhotosynthesis: Photosynthesis is the primary mode of food production in green plant. ” The process by which green plants synthesize food from simple substances carbon dioxide and water in the presence of sunlight is called Photosynthe…

Digestive System Of Human BodyDigestive system is a group of organs & associated digestive glands that take part in ingestion, digestive absorption of food & egestion of undigestible matter. Digestive organs from a continuous canal called alimen…