“A zwitterion is a molecule that has both positive and negative regions of charge.” In the solid state, amino acids exist as dipolar ions called zwitterions. In discussing whether a substance is zwitterionic or not the pH range in which the information is required must be specified, because a sufficiently alkaline solution will change the zwitterion to an anion, and a sufficiently acid solution will change it to a cation.

Activation energy

• The minimum quantitiy of external energy required for the conversion of reactant into product or to produce an unstable intermediate is called activation energy. It is E  
• Rate of reaction is inversely proportional to the activation energy.
• Therefore, greater value of activation energy leads to lower rate of reaction and increased influence of temperature change on the rate constant.

When the veins of a leaf show numerous irregular inter-connections giving the appearance of a network, it is called reticulate venation.

Erythropoiesis occurs mostly in bone marrow and ends in blood stream. Mature red blood cells are generated from multipotent hematopoietic stem cells, through a complex maturation process involving several morphological changes to produce a highly functional specialized cells. Red blood cells, most white blood cells, and platelets are produced in the bone marrow, the soft fatty tissue inside bone cavities. Two types of white blood cells, T and B cells (lymphocytes), are also produced in the lymph nodes and spleen, and T cells are produced and mature in the thymus gland.

Pines have needle like leaves. The needles of pines are arranged in a spiral about the stem. ... Like the leaves of all higher plants, pine needles have special microscopic pores on their surface, called stomata, which are important for exchange of water vapor, carbon dioxide, and oxygen. In particular, the outer surface of pine needles has a thick waxy layer, called a cuticle, which reduces evaporative water loss. At the microscopic level, the stomata are beneath the surface cells, so they are often called "sunken stomata." This stomatal adaptation reduces evaporative water loss.

Listed below are the raw materials used by an entity to obtain energy:

• All animals take in food, water and oxygen as raw material from the outside.
• As for plants, they take in carbon dioxide, water and sunlight to synthesize their own food in the presence of chlorophyll(found in green plants).

For manufacturing companies, raw materials inventory requires detailed budgeting and a special framework for accounting on the balance sheet and income statement. Examples of raw materials include: steel, oil, corn, grain, gasoline, lumber, forest resources, plastic, natural gas, coal, and minerals.

Archaebacteria are the most primitive bacteria, probably by the first form of life, which evolved in a different line from that of true bacteria. These are adapted to extreme conditions like an oxygeny, pH, salinity and temperature. They differ from true bacteria by cell wall lacks murein, cell membrane with lipids (glycerol isopronyl ether) of branched alipathic chains, smaller size of DNA and base constituents in the RNA. These are of three types- Methanogens (methane producing, cause explosion in coal mines), Halophiles (live in extreme saline conditions, contain purple pigment bacteriorhodopsin for ATP synthesis from sunlight) and Thermophiles or Thermoacidophiles (withstand high temperature and acidity, mostly grow in hot sulphur springs).

Hooks aid the organism in getting attached to the organs of the host and the suckers help it in absorbing nutrients from the host tissues.

Polysepalous: If sepals are free and not joined together, the calyx is said to be polysepalous. E.g. Rose, Mustard

Organisms which exhibit saprophytic mode of nutrition are called as saprophytes. Saprophytes obtain their nutrition from dead and decaying organic matter. Saprophytes secrete digestive juices onto dead and decaying matter to dissolve it and then absorb nutrients from it.

Dicotyledonous root

• The outermost layer is epidermis.
• The cortex consists of several layers of thin-walled parenchyma cells with intercellular spaces.
• The innermost layer of the cortex is called
• The tangential as well as radial walls of the endodermal cells have a deposition of water-impermeable, waxy material suberin in the form of casparian strips.
• Next to endodermis lies a few layers of thick-walled parenchyomatous cells referred to as pericycle.
• The parenchymatous cells which lie between the xylem and the phloem are called conjuctive tissue.
• There are usually two to four xylem and phloem patches, later a cambium ring develops between the xylem and phloem.
• All tissues on the inner side of the endodermis such as pericycle, vascular bundles and pith constitute the stele.