What tissue covers the outside of the body and lines organs within the body?

Passive transport is a type of nutrient exchange across a cell membrane that does not require the input of cellular energy (ATP). It relies on the inherent kinetic energy of molecules and the concentration gradient to drive the movement of substances across the membrane. Passive transport mechanisms include diffusion, facilitated diffusion, and osmosis. Diffusion is the spontaneous movement of molecules from an area of higher concentration to an area of lower concentration until equilibrium is reached. Facilitated diffusion involves the facilitated movement of specific molecules (e.g., ions, polar molecules) across the membrane through protein channels or carriers, following their concentration gradient. Osmosis is the passive diffusion of water molecules across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration. Unlike passive transport, active transport requires the expenditure of energy (ATP) to transport molecules against their concentration gradient, typically using protein pumps or carriers embedded in the membrane. Passive transport plays a crucial role in nutrient uptake, waste removal, and maintaining osmotic balance in cells and tissues.

In the taxonomic hierarchy, the family represents a higher-level grouping that includes related genera. In the classification provided, Elephantidae represents the family, encompassing all elephants. The specific epithet "indicus" refers to the Indian elephant, which is a subspecies of the Asian elephant.

Photosynthesis, the process by which green plants, algae, and some bacteria convert light energy into chemical energy in the form of glucose, takes place primarily in the chloroplasts of plant cells. Chloroplasts are specialized organelles found in the cells of photosynthetic organisms, where they are responsible for capturing light energy and using it to synthesize organic molecules through the process of photosynthesis. Chloroplasts contain chlorophyll, a green pigment that absorbs light energy from the sun. During photosynthesis, light energy is used to split water molecules (photolysis), releasing oxygen as a byproduct, and generate chemical energy in the form of ATP and NADPH. This energy is then used to drive the synthesis of glucose from carbon dioxide and water in a series of biochemical reactions known as the Calvin cycle. The glucose produced by photosynthesis serves as a source of energy and carbon for the plant and is used to fuel cellular respiration, growth, and reproduction.

Cellular respiration is the metabolic process by which cells convert biochemical energy stored in nutrients such as glucose into adenosine triphosphate (ATP), the universal energy currency of cells. Cellular respiration occurs primarily in the mitochondria, which are membrane-bound organelles found in the cytoplasm of eukaryotic cells. Mitochondria are often referred to as the "powerhouses" of the cell due to their role in ATP production through aerobic respiration. The process of cellular respiration involves several interconnected metabolic pathways, including glycolysis, the citric acid cycle (Krebs cycle), and the electron transport chain (oxidative phosphorylation). In glycolysis, glucose is partially oxidized to produce pyruvate and a small amount of ATP in the cytoplasm. Pyruvate is then transported into the mitochondria, where it enters the citric acid cycle, generating more ATP and reducing equivalents (NADH and FADH2). The reduced coenzymes NADH and FADH2 donate electrons to the electron transport chain located in the inner mitochondrial membrane, leading to the production of ATP through oxidative phosphorylation. Overall, cellular respiration is essential for providing energy for cellular processes such as biosynthesis, muscle contraction, active transport, and maintenance of cellular homeostasis.