(i) Pili and fimbriae are the two surface extensions that are not concerned with motility.
(ii) Structure that helps in motility of bacterial cell is flagella.

Because blood has to pass into the heart against the gravity so it leakes into interstitial spaces.

At hills, the pressure of air falls and the person cannot get enough oxygen in the lungs for diffusion into the blood.Due to deficiency of oxygen, the person feels breathlessness, headche, dizziness, nausea, mental fatigue and a bluish colour on the skin, nails and lips.

Bile is a yellowish green alkaline solution with 89-98% water, it has no digestive enzymes.the bile released into the duodenum contains bile pigments(bilirubin and biliverdin), bile salts, cholesterol and phospholipids, but no enzymes.Bile helps in emulsification of fats, i.e breaking down of the fats into very small micelles.Bile also activates lipases.

Relative growth rate of A\(=\frac { (10-5) }{ x\times 5 } =\frac { 5 }{ 5x } { cm }^{ 2 }\)
Relative growth rate of B\(=\frac { (55-50) }{ 50\times x } =\frac { 5 }{ 50x } { cm }^{ 2 }\)
Thus, A shows higher relative growth rate.

This process accounts for the greater speed of an impluse travelling along a myelinated neuron than along a non-myelinated  one. It is upto 50 times faster than the non-myelinated nerve fibre.

On reducing or removing the fifty per cent of leaves from plant, the rate of transpiration by the remaining leaves will decreases because the rate of transpiration is purely dependent upon the surface area of the leaves. Thus, plant with larger leaf surface area have higher rate of transpiration as compared to the plant with the areas of smaller leaf surface 

An analysis of the xylem exudates shows that through some of the nitrogen travels as inorganic travels as inorganic ions, much of it is carried in the organic form as amino acids and related compounds. Similarly, small amount of phosphorus and sulphur are carried as organic compunds.In addition, small amount of exchange of materials does take between xylem and phloem.

Gene expression, protein synthesis, secretion, motility etc, do not happen during M-phase.

Cotton fibre - Cellulose
Exoskeleton of cockroach - Chitin
Liver - Glycogen
Peeled Potato - Starch

A system at equilibrium cannot work. But, living organisms have to work continuously and cannot afford to reach equilibrium, so living state is a non-equilibrium steady-state.

Gums are sticky breakdown products of plants cell with consisting of polysacharides and pectins which excude from the wounds in the bark. They are generally water soluble.
Fevicol is a synthetic sticky substance called resin. Resins are insoluble in water.

Polyunsaturated oils contain fatty acids having one or more double bonds, the clotting property of blood decreases due to high proportions of PUFA. Thus, the possibility of blockage is reduced.

The body of a multicellular organism has cell as a basic structural unit. The cells are organised to form tissues such as blood, bone, etc. The tissue are organised to form organs such as heart, kidney, etc. The organs are then organised to form organ systems such as digestive system, reproductive system respiratory system, etc. The various organ system of organism gets arranged to form a complete individual.

The bones have excessive calcification . So it is difficult to sty living cells in an untreated bones. For their study , the bone id first decacified in the same way as architecture of the matrix is studied after drying up of the living materials.

Annelid characters Peripatus have jointed parapodia (legs), haemocoel, trachae for respiration and head with a pair of compound eyes and antennae.

Gymnosperms and angiosperms are classified separately although they both bear seed because of following reasons
i) Ovules in gymnosperms are naked. In angiosperms, they are enclosed inside the ovary.
ii) Wood is non-porous in gymnosperms,i.e, the vessels are absent. Wood in angiosperms is porous,i.e, the vessels are present.

The following reasons explain this
(i) In natural system of classification only related organisms occur in a group as it prevents grouping of unrelated organisms.
(ii) It shows natural relationship among organisms.

Chemotaxonomy or biochemical taxonomy is based on the protein and serum analysis and on the chemical constituents of the organisms. This type of taxonomy is particularly utilized in the classification of plants, as chemical constituents of plant species are stable and do not change easily.

Ascospore formation is the characteristic of class-Ascomycetes. Ascospores are a type of non-motile meiospores which are produced inside special sacs called asci (sing. ascus). An ascus often contains 8 ascospores because meiosis is accompanied by one mitotic division

Some fungi have evolved essential relationships with the roots of many living plants.
These fungi grow around and into the roots. Both partners benefit so that neither would thrive without the other. This partnership is called mycorrhizal symbiosis.

There are diverse habitats on earth hosting millions of living organisms. Due to limited number of taxonomists, absence of thorough survey of different areas and occurrence of several inaccessible regions, e.g., hot springs, underwater reefs, etc., it is difficult to identify all the organisms.

Botanists use binomial nomenclature to solve this problem.A scientific name is given to the plant based on certain principles and criteria.The scientific name of a particular plant is same all over the world and is not given to any other plant.

There are many organisms, which never reproduce in their life, although all other characteristic of living things are present in them, e.g., sterile worker bees, mules, infertile human couples, etc., Hence, reproduction cannot be an all-inclusive defining property of living things.