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The removal ofwastematerial from the body is called excretion. Theunicellular organism remove their wastesdirectly through the cell membrane by the process of diffusion. Diffusion occurs when particles

Thesubstances like CO2 and water move in and outof acellby diffusion from the region of high concentration to low concentration. When the concentration ofCO2 and wateris higher in external environment than that inside thecell,CO2 and water movesinside thecell

The substances like CO2 and water move in and out of a cell by diffusion from the region of high concentration to low concentration. When the concentration of CO2 and water is higher in external environment than that inside the cell, CO2 and water moves inside the cell. When the concentration outside the cell becomes low and it is high inside the cell, they moves out.

gasses like CO2 move by the process of diffusion but water moves in and out of the cell by osmosis

because cells have concentration of high to low

next please

A clayloam texturesoil, for example, has nearly equal parts of sand, slit, and clay.

solar radiation

it make skin cancer

ozone absorbs uv radiation which is very harmful for human body it causes skin cancer

if ozone layer destroy this will a result of big destruction because all we know that it proctect from sun uv rays but after destroy these rays will come in earth and ruin it by them destructive power it spread many diseases like skin cancer it is very dangerous. it's melt the skin. ozone layer is being destroy by human appliance like aerosol sprays.

Reproduction Is the correct answer

irratibility is the correct answer..Cockroaches have many sense receptors like antenna etc..so if they are touched they show immediate response of stimuli..

a option is correct which is metabolism because it is defining property

c.irritability is correct option

c.Irritability is correct

Option c. Irritability will help them to do so.

Microwaves are a form of electromagnetic radiation with wavelengths ranging from about one meter to one millimeter; with frequencies between 300 MHz and 300 GHz. Different sources define different frequency ranges as microwaves.

50% is photosynthesis active radiation

hope it helps you.......

genetic changes in organisms and cancers

in simple words it causes skin cancer

Fibres obtained from natural sources like plants and animals are called as Natural Fibres .Examples are Cotton, silk ,Jute, wool etc.

Advantages of Natural Fibres:--->They are made up of natural sources like plants and animals.---> Fire resistant.--->On burning the natural fibres we don't get poisonous gases.--->Easily affordable.---> Absorbs sweat and water hence these types of clothes are preferred to wear in summer.Disadvantages Of natural Fibres :---> Are not very strong compared to synthetic fibres.----> Natural Fibres are heavy in weight .---> Natural fibres can be damaged by moths.---> Not wrinkle free--->They are not durable.

Ans :-

Under colonial rule, the functions and powers of the tribal chiefs changedconsiderably. Though they were allowed to keep their land titles over a cluster ofvillages and rent out lands, the administrative, judicial and economic powers theyenjoyed before the arrival of the British were no longer in force. They were requiredto follow the British laws, pay tribute to the British and discipline the tribal groups onbehalf of the colonial masters. As a result, they lost the authority they had earlierenjoyed among their people, and were unable to fulfil their traditional functions.

Tall is a dominant character, and it generally masks the recessive character (dwarf) in F1generation.

A dominant character is the character which is expressed in the heterozygous condition. This means that whenever this character is present, it is expressed. So, whether it is present with any other character or the same character, it would be expressed.

A recessive character is the character which is expressed only in the absence of a dominant character. This means that this character is expressed only present in pairs. So, it is expressedonly when both the recessive alleles of a gene are present.

a) Easy to grow (b)Short lifespan : Pea plant complete it's life cycle in very short period of time.(c)Easily distinguishable characters(d)Larger size of flower(e)Self pollinated

easy to grow is it be available they are easy into crores and easy to form the F1 generation because it was easily available in the nearby and easy to grow withoutcare

Green plants are autotrophs since they synthesis their own food.

When a pair of contrasting characters is present together, only one trait appears in the first generation. This expressed trait is called dominant trait and the unexpressed trait is called the recessive trait.For example, when Mendel crossed a pure breed tall pea plant with a pure breed dwarf plant. He found that all the plants in the F1 generation were tall. That means, only tallness trait appeared in the F1 generation. Thus, it was the dominant trait while dwarfness was the recessive trait.

Mendel was the father of genetics ,his experimental research works are the building base of today's modern genetical engineering.

According to the question;

If he cross fertilize between a tall (TT) and a small (tt) pea plant,the results in the f1 progeny will be:

All the plants in the f1 progeny will be tall (Tt) due to the dominant characteristics of the tall gene (T).

Mendel was the father of genetics ,his experimental research works are the building base of today's modern genetical engineering.

According to the question;

If he cross fertilize between a tall (TT) and a small (tt) pea plant,the results in the f1 progeny will be:

All the plants in the f1 progeny will be tall (Tt) due to the dominant characteristics of the tall gene (T).

Mendel selected garden pea plant (Pisum sativum) for his experiments because of the followingcharacteristics:

ii. The flowers are bisexual and naturally self pollinating.iii. They can be artificially cross-pollinated.iv. The offsprings produced after cross pollination are fertile.v. Pea plant has several pairs of contrasting characters.vi. Flowers of pea plant are large enough for easy emasculation.vii. It is a small herbaceous plant, so he could grow large number of plants.

a) Mendel demonstrated that traits can be either dominant or recessive through his monohybrid cross.

He crossed true-breeding tall (TT) and dwarf (tt) pea plants. The seeds formed after fertilisation were grown and the plants that were formed represent the first filial or F1 generation.

All the F1 plants obtained were tall. Then, Mendel self-pollinated the F1 plants and observed that all plants obtained in the F2 generation were not tall.

Instead, one-fourth of the F2 plants were short. From this experiment, Mendel concluded that the F1 tall plants were not true breeding; they were carrying traits of both short height and tall height.

They appeared tall only because the tall trait was dominant over the dwarf trait. This shows that traits may be dominant or recessive.

Algae are eukaryotic organisms that have no roots, stems, or leaves but do have chlorophyll and other pigments for carrying outphotosynthesis.

Unicellular algae occur most frequently in water, especially in plankton.

Full form is Medical termination of pregnancy. It is used to kill the unborn child if they are suffering from genetically disorder disease

total three weightssum of two weights27kg 325g+32kg 777g59kg 1102gm60kg 102gm as 1000gm=1kg95 kg=94kg 1000gmweight of third girl94kg1000gm-60kg 102gm34kg 898gm

koshika kya hai

P-iii (rod shaped bacteria)Q-ii (diplococcus) R-iv (spiral shaped spirochaetes)S- i (comma shaped vibrio)

mmediate response to stimuli. The plants do not posses nervous system for the conduction of the impulse but still it shows immediate response to stimuli. The plant Mimosa pudica is well known for its rapid plant movement. ... The leaves also close up under various other stimuli, such as touching, warming, or shaking.

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c) it is a position response because it is a germinate.. and grow into plant

plants growing through roots by their xylem and phloem parts

c)it is a position response because it is a germinate.. and grow into plant

Ans :- Astimulus canbe internal or external. Sense organs, such as the ear, and sensory receptors, such as those in the skin,aresensitive to external stimuli such as sound and touch. Something that has an impact or an effect on an organism so that its behavior is modified in a detectable way.

Geotropism helps the plant to bend away from stimulus

Geotropism:The growth of the parts of plants in response to the force of gravity. The upward growth of plant shoots is an instance of negative geotropism; the downward growth of roots is positive geotropism

Decomposers and scavengers break down dead plants and animals. They also break down the waste (poop) of other organisms. Decomposers are very important for any ecosystem. If they weren't in the ecosystem, the plants would not get essentialnutrients, and deadmatterand waste would pile up.

(a) diesel;

(b) glass;

(c) matchstick;

(d) heat, flame;

(e) calorific

can u short it I don't able to unsderstand it ok

METAMORPHOSIS: The Lifecycle of a Frog

Metamorphosis is the change of shape during an animal’s life. During metamorphosis the tadpole will develop back legs first, then front legs. Around 6 weeks of life the mouth starts to widen. Sometime around 10 weeks the froglet’s, as it is now called, eyes start to bulge out and the tail begins to shrink and eventually disappear. When the lungs finish developing the froglet makes it’s way onto the land and, Ta-da! It’s a frog!

2)When ripe pollen from an anther of the same kind offlowercatches on the stigma, each pollen grain sends out a tiny threadlike tube. The tube grows down through the style and pierces one of the ovules in the ovary. Thisprocessis calledfertilization.

3)Various ways by which seeds are dispersed are: (i) Dispersal by wind:Lightseeds or hairy seeds and hairyfruitget blown off with the wind to far away places. Examples:Sunflower, maple, drumsticks etc.

thanks

in which place renovier node present

because pollen is blown by the wind to land on the female cones. Although manyangiospermsare also wind-pollinated, animalpollinationis more common.

because pollen is blown by the wind to land on the female cones. Although manyangiospermsare also wind-pollinated, animalpollinationis more common.

mitosis

carbon dating is a technique of finding out the age of organic matters like fossils, wood, leather etc. by comparing the amount of radio carbon present in them. This is used by archeologists to determine the age of fossil remains at archeologists. In nature carbon is found in various forms and is present in living organisms. Radio carbon dating is only possible with the materials that were once associated with living things. Thus age of inorganic materials cannot be determined by this methods like stone etc.Method:It depends on the decay of the radioactive isotope carbon-14 (radiocarbon) to nitrogen.Carbon dating is a method to estimate the age of carbon containing materials like trees. Carbon (C) has three naturally occurring isotopes. Both C-12 and C-13 are stable, but C-14 decay to nitrogen-14 with a half-life of approximately 5,730 years. Animals and plants naturally incorporate both the C-12 and C-14 during their lifetimes. When a creature dies, it ceases to consume more radiocarbon while the C-14 already in its body continues to decay back into nitrogen. With the help of C-12 to C-14 ratio, we can estimate the age of dead plants/ animals.thumb up plzzz

Carbon 14 iscontinually being formed in the upper atmosphere by the effect of cosmic ray neutrons on nitrogen14atoms. Itisrapidly oxidized in air to formcarbondioxide and enters the globalcarboncycle. ...Radiocarbon dating isessentially amethoddesigned to measure residual radioactivity.

Carbon-14 is a weakly radioactive isotope of Carbon; also known as radiocarbon, it is an isotopic chronometer.

C-14 datingis only applicable to organic and some inorganic materials (not applicable to metals).

Gas proportional counting, liquid scintillation counting and accelerator mass spectrometry are the three principal radiocarbon dating methods.

What is Radiocarbon Dating?

Radiocarbon dating is a method that provides objective age estimates for carbon-based materials that originated from living organisms.1An age could be estimated by measuring the amount of carbon-14 present in the sample and comparing this against an internationally used reference standard.

The impact of the radiocarbon dating technique on modern man has made it one of the most significant discoveries of the 20th century. No other scientific method has managed to revolutionize man’s understanding not only of his present but also of events that already happened thousands of years ago.Archaeologyand other human sciences use radiocarbon dating to prove or disprove theories. Over the years, carbon 14 dating has also found applications in geology, hydrology, geophysics, atmospheric science, oceanography, paleoclimatology and even biomedicine.

Basic Principles of Carbon Dating

Radiocarbon, or carbon 14, is an isotope of the element carbon that is unstable and weakly radioactive. The stable isotopes are carbon 12 and carbon 13.

Carbon 14 is continually being formed in the upper atmosphere by the effect of cosmic ray neutrons on nitrogen 14 atoms. It is rapidly oxidized in air to form carbon dioxide and enters the global carbon cycle.

Plants and animals assimilatecarbon 14from carbon dioxide throughout their lifetimes. When they die, they stop exchanging carbon with the biosphere and their carbon 14 content then starts to decrease at a rate determined by the law of radioactive decay.

Radiocarbon dating is essentially a method designed to measure residual radioactivity. By knowing how much carbon 14 is left in a sample, the age of the organism when it died can be known. It must be noted though that radiocarbon dating results indicate when the organism was alive but not when a material from that organism was used.

Measuring Radiocarbon – AMS vs Radiometric Dating

There are three principal techniques used to measure carbon 14 content of any given sample— gas proportional counting, liquid scintillation counting, andaccelerator mass spectrometry.

Gas proportional counting is a conventionalradiometric datingtechnique that counts the beta particles emitted by a given sample. Beta particles are products ofradiocarbondecay. In this method, the carbon sample is first converted to carbon dioxide gas before measurement in gas proportional counters takes place.

Liquid scintillation counting is another radiocarbon dating technique that was popular in the 1960s. In this method, the sample is in liquid form and a scintillator is added. This scintillator produces a flash of light when it interacts with a beta particle. A vial with a sample is passed between two photomultipliers, and only when both devices register the flash of light that a count is made.

Accelerator mass spectrometry (AMS) is a modern radiocarbon dating method that is considered to be the more efficient way to measure radiocarbon content of a sample. In this method, thecarbon 14content is directly measured relative to the carbon 12 and carbon 13 present. The method does not count beta particles but the number of carbon atoms present in the sample and the proportion of the isotopes.

Carbon-14 Datable Materials

Not all materials can be radiocarbon dated. Most, if not all, organic compounds can be dated. Some inorganic matter, like a shell’s aragonite component, can also be dated as long as the mineral’s formation involved assimilation of carbon 14 in equilibrium with the atmosphere.

Samples that have been radiocarbon dated since the inception of the method includecharcoal,wood, twigs,seeds,bones,shells, leather,peat, lake mud,soil, hair,pottery,pollen, wall paintings, corals, blood residues,fabrics, paper or parchment, resins, andwater, among others.

Physical and chemical pretreatments are done on these materials to remove possible contaminants before they are analyzed for their radiocarbon content.

Carbon Dating Standards

The radiocarbon age of a certain sample of unknown age can be determined by measuring its carbon 14 content and comparing the result to the carbon 14 activity in modern and background samples.

The principal modern standard used by radiocarbon dating labs was the Oxalic Acid I obtained from the National Institute of Standards and Technology in Maryland. This oxalic acid came from sugar beets in 1955. Around 95% of the radiocarbon activity of Oxalic Acid I is equal to the measured radiocarbon activity of the absolute radiocarbon standard—a wood in 1890 unaffected by fossil fuel effects.

When the stocks of Oxalic Acid I were almost fully consumed, another standard was made from a crop of 1977 French beet molasses. The new standard, Oxalic Acid II, was proven to have only a slight difference with Oxalic Acid I in terms of radiocarbon content. Over the years, other secondaryradiocarbon standardshave been made.

Radiocarbon activity of materials in the background is also determined to remove its contribution from results obtained during a sample analysis. Background radiocarbon activity is measured, and the values obtained are deducted from the sample’s radiocarbon dating results. Background samples analyzed are usually geological in origin of infinite age such as coal, lignite, and limestone.

Carbon 14 Dating Measurements

A radiocarbon measurement is termed a conventional radiocarbon age (CRA). The CRA conventions include (a) usage of the Libby half-life, (b) usage of Oxalic Acid I or II or any appropriate secondary standard as the modern radiocarbon standard, (c) correction for sample isotopic fractionation to a normalized or base value of -25.0 per mille relative to the ratio of carbon 12/carbon 13 in the carbonate standard VPDB – Cretaceous belemnite formation at Peedee in South Carolina, (d) zero BP (Before Present) is defined as AD 1950, and (e) the assumption that global radiocarbon levels are constant.

Standard errors are also reported in aradiocarbon dating result, hence the “±” values. These values have been derived through statistical means.

Radiocarbon Dating Pioneer

American physical chemist Willard Libby led a team of scientists in the post World War II era to develop a method that measures radiocarbon activity. He is credited to be the first scientist to suggest that the unstable carbon isotope called radiocarbon or carbon 14 might exist in living matter.

Mr. Libby and his team of scientists were able to publish a paper summarizing the first detection ofradiocarbonin an organic sample. It was also Mr. Libby who first measured radiocarbon’s rate of decay and established 5568 years ± 30 years as the half-life.

In 1960, Mr. Libby was awarded the Nobel Prize in Chemistry in recognition of his efforts to develop radiocarbon dating.

The stable isotopesare carbon12 andcarbon13.Carbon 14 iscontinually being formed in the upper atmosphere by the effect of cosmic ray neutrons on nitrogen14atoms. ...Radiocarbon dating isessentially amethoddesigned to measure residual radioactivity.

The environmentalimpact of miningincludes erosion, formation of sinkholes, loss of biodiversity, and contamination of soil, groundwater, and surface water by chemicals fromminingprocesses. ... Someminingmethods may have significant environmental and public healtheffects.

Ozonethus plays a keyrolein the temperature structure of the Earth'satmosphere. Without the filtering action of theozone layer, more of the Sun's UV-B radiation would penetrate theatmosphereand would reach the Earth's surface.

Ozoneis a gas in theatmospherethat protects everything living on the Earth from harmful ultraviolet (UV) rays from the Sun. Without thelayerofozonein theatmosphere, it would be very difficult for anything to survive on the surface.

The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity.The atmosphere can be divided into layers based on its temperature. These layers are the troposphere, the stratosphere, the mesosphere and the thermosphere. A further region, beginning about 500 km above the Earth's surface, is called the exosphere.

if we get jaundice as it has more long time effect in our health. It is caused by an excess of bilirubin, a substance created when red blood cells break down.