Rhizome, also called creeping rootstalk, horizontal underground plant stem capable of producing the shoot and root systems of a new plant.

Examples of plants which propagate by rhizome includes:

* Hops
* Asparagus
* Ginger
* Irises
* Lily of the valley
* Cannas
* Sympodial orchids

Tests for gases

Hydrogen

A lighted wooden splint makes a popping sound in a test tube of hydrogen.

Oxygen

A glowing wooden splint relights in a test tube of oxygen.

Carbon dioxide

Carbon dioxide turns limewater milky. A lighted wooden splint goes out in a test tube of carbon dioxide but this happens with other gases, too. So the limewater test is a better choice.

Ammonia

Ammonia has a characteristic sharp, choking smell. It also makes damp red litmus paper turn blue. Ammonia forms a white smoke of ammonium chloride when hydrogen chloride gas, from concentrated hydrochloric acid, is held near it.

Chlorine

Chlorine has a characteristic sharp, choking smell. It also makes damp blue litmus paper turn red, and then bleaches it white. Chlorine makes damp starch-iodide paper turn blue-black.

Prunning the selective removal of certain parts of a plant, such as branches, buds, or roots.

Weeding is the process to remove out the weeds. Weeds are unwantedvplants which grown along the useful crops.

Staking is the practice of driving a stake or rod into the ground close to a plant to provide support for its stems

Grafting and budding are techniques used to join parts from two or more plants so that they appear to grow as a single plant. In grafting, the upper part (scion) of one plant grows on the root system (rootstock) of another plant. In the budding process, a bud is taken from one plant and grown on another

Valves in veins prevent blood from flowing in the reverse (backward) direction.

Venous valves typically consist of two elastic flaps of tissue that open and close in alternation.

Muscles constantly contract and release, causing the blood to flow toward the heart. The valves open, allowing the blood to flow, and close, stopping the blood from flowing backwards.

Use of pesticides, overgrazing and mining destroy the environment

Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature reserves.

Afforestation is the establishment of a forest or stand of trees (forestation) in an area where there was no previous tree cover to create forests.

Afforestation help slowing down global warming, by reducing CO₂ in the atmosphere and introducing more O₂.

Pitch

Pitch is a term used to describe how high or low a note a being played by a musical instrument or sung seems to be.

The pitch of a note depends on the frequency of the source of the sound.

Frequency is measured in Hertz (Hz), with one vibration per second being equal to one hertz (1 Hz).

A high frequency produces a high pitched note and a low frequency produces a low pitched note.

Loudness

Loudness depends on the amplitude of the sound wave.

The larger the amplitude the more energy the sound wave contains therefore the louder the sound.

Quality

This is used to describe the quality of the waveform as it appears to the listener. Therefore the quality of a note depends upon the waveform.

Two notes of the same pitch and loudness, played from different instruments do not sound the same because the waveforms are different and therefore differ in quality or tone.

Harvesting cocoa

Harvesting casava

Harvesting tomato

Harvesting yam

The solar radiation from the Sun provides the input of energy which is used by primary producers, also known as autotrophs. Primary producers are usually plants and algae, which perform photosynthesis in order to manufacture their own food source. Primary producers make up the first trophic level.

The rest of the trophic levels are made up of consumers, also known as heterotrophs; heterotrophs cannot produce their own food, so must consume other organisms in order to acquire nutrition.

The second trophic level consists of herbivores, these organisms gain energy by eating primary producers and are called primary consumers.

Examples of primary consumers

Cows, sheep, rabbits, deer, goats, bats, birds,monkeys,arachnids (spiders),termites, beetles etc.

Trophic levels three, four and five consist of carnivores and omnivores. Carnivores are animals that survive only by eating other animals, whereas omnivores eat animals and plant material.

Trophic level three consists of carnivores and omnivores which eat herbivores; these are the secondary consumers.

Examples of secondary consumers

Frogs, weasels,lions, eagles,snakes etc.

Trophic level four contains carnivores and omnivores which eat secondary consumers and are known as tertiary consumers.

Examples of tertiary consumers

Owls

Bauxite is primarily comprised of aluminum oxide compounds (alumina), silica, iron oxides and titanium dioxide. Alumina is then refined into pure aluminum metal

Brine is a high-concentration solution of salt (NaCl) in water (H₂O)

Gold is a chemical element with the symbol Au (from Latin: aurum) and atomic number 79

Steel is an alloy of iron with typically a few percent of carbon to improve its strength and fracture resistance compared to iron.

Frictional force refers to the force generated by two surfaces that contacts and slide against each other. A few factors affecting the frictional force: These forces are mainly affected by the surface texture and amount of force impelling them together.

Ways of reducing friction

1. The use of bearing surfaces that are themselves sacrificial, such as low shear materials, of which lead/copper journal bearings are an example.

2. Replace sliding friction with rolling element friction, such as with the use of rolling element bearings.

3. Improve overall lubrication either by changing viscosity, using differing or improved additives or through the use of different lubricants themselves, i.e., synthetics, solids, etc.

The Digestive Tract of A Goat

Goats are ruminants, animals with a four-compartment stomach, as are cattle, sheep and deer. The compartments are the reticulum, rumen, omasum and abomasum, or true stomach.