Life Processes: Nutrition Quiz

Life Processes: Nutrition

Nutrition is a fundamental life process that involves the intake and utilization of food by living organisms to maintain their growth, repair, and overall well-being. Nutrients are the substances required for proper growth and maintenance of the living body. All living organisms acquire nutrients differently, depending on their mode of nutrition. Nutrition can be classified into two main types: autotrophic and heterotrophic.

Autotrophic Nutrition

Autotrophic organisms, such as green plants and some bacteria, can synthesize their food from simple inorganic substances like carbon dioxide and water in the presence of sunlight and chlorophyll. This process, called photosynthesis, results in the production of organic compounds, primarily glucose and oxygen. Green plants are autotrophs, and their mode of nutrition is called photoautotrophic. They use light energy to convert carbon dioxide and water into glucose and oxygen. Bacteria, on the other hand, are chemoautotrophs, using chemical energy to synthesize food from inorganic substances.

Heterotrophic Nutrition

Heterotrophic organisms, like animals, fungi, and other bacteria, cannot synthesize their food on their own. They obtain their energy from organic molecules already produced by autotrophs. Heterotrophic nutrition is further divided into three main types: holozoic, saprophytic, and parasitic.

• Holozoic Nutrition: In this mode of nutrition, organisms ingest, digest, and absorb food. Multicellular animals, including humans, and some unicellular organisms like amoeba and Paramoecium follow this mode.
• Saprophytic Nutrition: In this mode, organisms feed on dead and decaying matter. Fungi are an example of saprophytes. They break down the organic matter and absorb the nutrients.
• Parasitic Nutrition: Some organisms obtain their food by feeding on living organisms. Roundworms and Plasmodium are examples of parasites. They obtain nutrients from the body of another living organism, known as the host.

Nutrition in Amoeba

Amoeba, a unicellular organism, obtains nutrition through a process called phagocytosis. It engulfs food particles, digests them, and absorbs the nutrients. The mode of nutrition in Amoeba is holozoic.

Nutrition in Paramoecium

Paramoecium, another unicellular organism, also follows a holozoic mode of nutrition. It ingests food particles using cilia, a type of hair-like structure. The food vacuole, a membrane-bound organelle, contains the ingested food.

Nutrition plays a crucial role in the survival and growth of living organisms. It provides the energy and essential nutrients required for various life processes and helps maintain the body's structure and function. Understanding the different modes of nutrition and their significance in the lives of various organisms is essential for comprehending the complexity and diversity of life processes.