Environmental factors and their measurements - class-VIII

A point source of pollution is a single, identifiable source, such as a pipe or a smokestack, from which pollutants are discharged.

The Olive Ridley turtle is famous for the 'arribada', a mass nesting phenomenon where thousands of females come ashore to lay eggs simultaneously.

Ultraviolet (UV) radiation is a known carcinogen and skin irritant. Sunburn, actinic keratosis, and solar elastosis are all well-documented dermatological consequences of chronic or acute UV exposure.

Rainwater infiltrates the soil and percolates downward into aquifers due to the force of gravity. This process is known as infiltration or groundwater recharge.

Aquatic biomes are broadly categorized into two main types based on salinity: marine biomes (saltwater) and freshwater biomes.

Turbidity, which measures the cloudiness or haziness of a fluid, is measured using an instrument called a turbidimeter or nephelometer.

The stratosphere extends from the tropopause (about 10-15 km) up to the stratopause, which is located at an altitude of approximately 50 km.

There are many external forces, substances or condition which affect the living organisms in one or the other way. They are considered as factors. These entire factors combine together to form an environment.

Heated water, often discharged from industrial plants, causes thermal pollution. This reduces dissolved oxygen levels and disrupts the metabolic processes of marine organisms.

In atmosphere, the nitrogen is present in large quantity about 78%. In our body, nitrogen is about 3%. During inspiration we take $O _2$ with various gases and nitrogen is one of them. During exhalation, the nitrogen comes out with $CO _2$.

Green house gases (e.g. CO$ _{2}$, CH$ _{2}$, CFCs etc.) are increasing in the atmosphere due to human and natural activities. These gases trap the heat(infra-red radiation) reflected by the earth. This heats up the atmosphere(leads to an increase in earth's temperature). This phenomenon is called global warming which occurs due to green house effect.

The open ocean is typically divided into three main vertical zones based on light penetration: the euphotic zone, the disphotic (twilight) zone, and the aphotic (midnight) zone.

In waste management, trenches are commonly excavated to serve as cells for landfilling, where waste is buried and covered with soil.

The blue color of the sky is caused by Rayleigh scattering, where shorter wavelengths (blue light) are scattered more efficiently by air molecules than longer wavelengths.

Biome is an interaction between various communities of organisms and the environment they live in. These communities of organisms dwell in similar geographical, climatic and other biotic factors.

The environmental conditions in these region are favourable and hence species have become diversified.

In the metric system, the prefix 'mega-' denotes a factor of 10^6, which is one million.

Sulphur shower : In the month of May, on hills the  yellow Pollen grains of Pinus Plants are Produced in lot of number and are scattered in air.

Acclimatization is the development of a favourable morphological and physiological response to a change In environment.

The organisms that use external heat to maintain their body temperature are termed as ectotherms while those maintaining their body temperature using the metabolic heat are termed as endotherms (mammals and aves). Among the given options, Blue jay (aves) is endotherms. 

At the molecular level even living things are fundamentally made up of all the elements that make non-living matter. There have been attempts to make these molecules and their integration to create life by scientists but none of them has been successful yet. Hence, it is often believed that there is a vital force that can not be created by us that gives organisms characteristics of life. 

Biotic potential refers to the maximum reproductive capacity of an organism under optimal environmental conditions. It works in opposition to environmental resistance, which limits population growth based on resource availability and environmental constraints.

An object appears red because it reflects (scatters) red wavelengths of light and absorbs the other wavelengths in the visible spectrum.

Environmental education is inherently interdisciplinary because it integrates concepts from biology, chemistry, geography, sociology, and economics to address complex environmental issues.

UNCED refers to the United Nations Conference on Environment and Development, also known as the Earth Summit held in Rio de Janeiro in 1992.

Animals with constant body temperature are called homoootherms. They have insulating coat to check the loss of body heat. This coat consists of hair in most mammals, blubber (subcutaneous fat) in whales and perspiration cools down the body of these animals when required.These are also termed endothermic as they regulate their body temperature by physio;logical means and maintain more or less constant internal temperature. Poililotherms are cold-blooded animals which are unable to regulate their body temperature which changes with change in temperature of environment e.g. fish, frog, lizard. They are also called as ectothems.

Tropical rainforests are disappearing fastly from India due to deforestation, habitat loss and fragmentation. These forests are of extreme value since they contain the maximum biodiversity.  

Topography means the physical features of a place such as hills, plains, slopes, rocks, valleys,etc. The topography affects the distribution of organisms directly or indirectly by influencing other factors, such as light intensity, wind velocity nature of sol, rainfall water currents or wave action. 

The sun's surface emits about 63 million watts of energy per square meter. By the time it reaches the Earth, after traveling 150 million kilometers, or 93 million miles, it has dimnished to 1,370 watts per square meter which are equal to thousand of kilocalories.

Environmental variation refers to differences in traits caused by external factors rather than genetics. Dyeing hair is an acquired trait influenced by the environment, not inherited.

Osmocoformers are the organisms that change the osmotic concentration of their body with the change in ambient conditions. Their body fluids are in osmotic balance with the environment For many marine invertebrates the osmolarity and ionic concentrations of their body fluids are similar to those of the sea water in which they live. 

Photosynthesis is a process that converts $CO _2$ into organic compounds and starch (carbohydrate) using energy from sunlight. $O _2$ is also released during this process.

The UNEP (United Nations Environment Program) has passed many environmental conservation acts. To create awareness of the condition, to encourage participation on public level, developing International Environmental Law etc. are its objectives.

Aquatic organisms are used to a certain range of temperature in the water-body where they live. A sudden marked change in this temperature can be dangerous for them. It affects breeding of aquatic animals. The eggs and larvae of various animals are particularly susceptible to temperature changes.

Terrestrial vegetation participates in gas exchange through stomata, taking in carbon dioxide for photosynthesis and releasing oxygen and water vapor.

Benthic organisms are those that live on or in the bottom sediments of a body of water, such as the benthos of a lake or river.

The marine biome is defined by high salt concentration and includes oceans, coral reefs, and estuaries, as opposed to freshwater biomes like lakes and rivers.