Wednesday, June 30, 2021

NUTRITION IN HUMAN BEINGS:

NUTRITION IN HUMAN BEINGS:Other than plants, all the organisms in this world are consumer. Consumer cannot prepare their own food , they depend upon plants to get their food.So all the organisms other than plants are called as  heterotrophs . Human beings are also heterotrophs. Human beings mainly take six different types of food - they are  Protein, Carbohydrates, Fats , Vitamins, Minerals and water. Out of these six different types of food - Protein, Carbohydrates, Fats are called  complex food and other three Vitamins, Minerals and water are called simple food. Food are termed as complex and simple based on the digestion and absorption by the epithelial lining of the alimentary canal.



Even though our alimentary canal starts from mouth and ends in the anus  but there is specific site for the digestion of  each type of food. So out of six different types of food only complex food material, digestion is complicated process and we need to understand them very clearly to understand the whole  process of digestion.



Protein when get digested break down to form amino acids. Carbohydrates after digestion forms glucose and fructose and fats on digestion gives fatty acids and glycerol.

We also need to know, the source from where we get get our six components of food. 

We get Protein from - eggs, meat, fish , soybean, pulses , milk etc. 

Carbohydrates we get from  Rice, potato, maize , barley., wheat etc., 

Fats we get  from Oil, ghee, butter and all the milk products.

Minerals we get from Fruits, vegetables etc.

Vitamins from fruits, vitamins etc and  Water.

Along with these food we also need Roughage which provide us fibre for eliminating the waste from our body. Cabbage is the best example.

Now ,we also need to know function of each type food -

Protein builds our body and heals the wounds.

Carbohydrates give us energy to do our daily activites.

Fats serve as stored energy, When there is need of severe energy in the body then fats supply that energy.

Vitamins and Minerals protect our body from germs.

And water helps in transportation.

Theses are the basic knowledge in Digestion before we give our steps in knowing the mechanism of digestion in our body.



 


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HUMAN SPERM


HUMAN SPERM: Human sperm is the haploid gamete of the Male. By the process of spermatogenesis there is there is formation of sperm.Germ cells undergo Mitosis division followed by Meiosis finally haploid sperm is formed which is n, having 23 number of chromosomes. A sperm generally consist of following parts - Head , Neck, Middle piece and Tail. 





Head is a rounded or globular structure. It contains nucleus, cytoplasm and other granules. Nucleus contains chromosomes and it has in it DNA -the genetic material or the hereditary material.Externally the head is covered by a membrane . Anterior portion of the head there is the occurrence of Acrosome. Acrosome helps in dissolving the membrane that surrounds the Egg.


  



Next to Head is the Neck. Neck posses two centrioles, they are named as Proximal centriole and the Distal centriole. Proximal centrioles plays a great role in the first cleavage of the zygote and Distal centrioles helps in the formation of Axial filament.






Middle piece is more in length than Head or Neck portion. It contains Mitochondria. Mitochondria is the store house of  energy ie. ATP. This energy is needed by the sperm to swim inside the female grnital tract.
Finally we find the tail.Tail is the long slender structure which is the  cytoplasmic extension.  Tail helps in the movement of the sperm.









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Monday, June 28, 2021

RESPIRATION IN HUMANS

 Respiration in Humans; Human beings has a well defined respiratory system Air that we breathe in enters through the nostrils which are line by hairs to filter the air that enters, Nostrils are also lined with mucous which is sticky in nature and absorbs any dust and other particles that enters, After that air passes through trachea. Trachea has rings of cartilage which prevents from collapsing if air enters through  great force.




 Trachea bifurcate after descending a little and forms two bronchi . Bronchi  then enters the Lungs.and inside the lungs it branches to form fine network like structure called bronchiloes. Human being posses a pair of lungs. Functional unit of lungs is called as Alvulus ( pl.Alveoli). It is a sac or balloon like structure. Alveoli is surrounded by blood capillaries and helps in the exchange of gasses.




Process of respiration in human can be divided into two main parts - Inhalation and Exhalation or Inspiration and Expiration. In inhalation or inspiration we take oxygen from the mixture of gases and in exhalation or expiration we give out carbondioxide as waste gas from our body. Different organs of our body like ribs, diaphragm, intercostal muscles etc.plays a great role in the process of respiration.





Sunday, June 27, 2021

RESPIRATION

 Respiration: Respiration is a biochemical process in which the food materials are broken down to give energy. We human beings and other higher organism  take oxygen to break down the food materials to get energy. The food that we take is glucose and glucose is six carbon molecule. In the first step six carbon compound glucose breaks down in the  cytoplasm to give pyruvic acid. Pyruvic acid is also called as pyruvate which is a three carbon molecule. After the formation of pyruvate, next step differ from organism to organism. In lower organism like Yeast, Bacteria etc. braking down of pyruvate takes place in absence of oxygen, this is called as fermentation and produces Energy, Ethanol and carbon dioxide. Process is also termed as Anaerobic process.



 In our case and all the higher organism Pyruvic acid breaks down to form Energy, Carbon dioxide and moisture. Here the breaking down of pyruvic acid takes place in presence of oxygen so it is termed as Aerobic process.


Sometimes there may be lack of oxygen in our muscles  even though our respiration is aerobic then this type of respiration is termed as Lack of oxygen respiration. It leads to the formation of  Lactic acid and releases energy.Due to the accumulation of lactic acid it leads to the occurrence of  cramps.




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Saturday, June 26, 2021

STRUCTURE OF OVUM

 

Structure Of Ovum: After the process of oogenesis -  an egg or the ovum is formed . Egg is released during the ovulation phase.

 


 Ovum is rounded, non motile cell. It is almost  free of  yolk and is called as alecithal. It has abundant cytoplasm , called ooplasm. It has a nucleus called as Germinal vesicle and there is the prominent occurrence of nucleolus. The nucleolus is surrounded by plasma membrane called  oolemma.  


There are no centrioles in the ovum. The ovum shows polarity. Its side which extrudes polar bodies called animal pole. The opposite side is called vegetal  pole. The ovum is enclosed by two additional egg coats: inner thin, transparent , non cellular zona pellucid and outer thick corona radiate.  

Zona  Pellucida is secreted by ovum itself and is called primary egg membrane. It is formed of three different glycol proteins. The corona radiate is formed of radically elongated follicular cells.




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GAMETOGENESIS : OOGENESIS

 

Gametogenesis –Oogenesis:  Gametogenesis is the process of formation of gametes. It is divided into two parts - Spermatogenesis and Oogenesis. Spermatogenesis is the formation of sperms and Oogenesis is the formation of egg or ova.



The process of formation of mature female gamete is called oogenesis.   It is divided into following stages ;

a)Multiplication Phase

b)Growth Phase

c) Maturation phase



Multiplication Phase –At the time of fetus development inside the mother’s womb there is the occurrence of another development in female that is the development of Egg mother cells or oogonia. No more oogonia are formed and added after birth. The egg mother cells or oogonia are larger cells with large nuclei and other constituents. These cells undergo mitosis division and increases in number. Oogonia are diploid or 2n having 46 chromosomes. Oogonial cells after the formation in huge number project into the stroma as a cord then becomes a round mass called the egg nest. One of the cell of the egg nest grows and becomes the primary oocytes. It is the future ovum. Other oogonia surrounds around the primary oocytes   to protect and give nourishment. Primary oocytes cells starts division and enters into the prophase I of the meiotic division but get temporarily arrested at this stage.



Growth Phase- In the growth phase development of primary oocytes takes place. Here along with the development of primary oocytes , follicle development also takes place. So this phase shows the development of Graulosa cells, Primary follicles, theca cells , secondary follicles etc.  It is a very long phase.



Maturation phase : In this phase, Primary oocytes completes its first meiosis and then second meiosis. In meiosis cell division there is the occurrence of 4 cells, here also it occurs but are all the cells that are formed not same. Out the four cells that develop here, 3 are small and is called as polar bodies and one is only big that is the egg or ootid.






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Tuesday, June 22, 2021

BLOOD CIRCULATION : HUMAN HEART

BLOOD CIRCULATION : HUMAN HEART - Human heart is a muscular organ and it is the size of our fist. Heart is the central pumping and pumps blood to the different parts of the body. Heart consist of four chambers- two Auricles and two Ventricles. The chambers are named as right and left- auricles and ventricles. The heart is placed in between the lungs.The heart is protected by double wall membrane called pericardium. In between the two layers of pericardium there is the occurrence of  pericardial fluid, which protect the heart from heat, shock etc. 



Some of the points regarding Heart we need to know before knowing circulation , like-

Impure blood from different parts of the body reaches the heart through veins. Impure blood is also called Deoxygenated Blood

Pure Blood from the heart reaches different part of the Aorta. Arteries carry pure blood . Pure blood is also known as oxygenated blood






Pulmonary Artery is the only artery in our body that carries impure blood.

Pulmonary Vein is the only vein in our body that carries pure blood.

Blood from the heart goes to the lungs for purification. In this case impure blood from right ventricle moves to the lungs. In the lungs purification of blood takes place. Blood from Deoxygenated become oxygenated. 

Colour of the heart is brown, where as auricles are lighter than ventricles. And again out of the two ventricles left ventricle is darker. The reason behind the dark colour is that both the auricle pour its blood to ventricles which are located below the auricles. But auricles need to pump blood outside the heart.

Left ventricle is darker than right ventricle because the left ventricle need to pump blood to different parts of the body where as right auricle pumps blood to the lungs.

Transportation of blood takes place through definite vessels called blood vessels. Different types of blood vessels are Arteries, veins and capillaries.












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GAMETOGENESIS : SPERMATOGENESIS

Gametogenesis is the process of formation of gametes. It is divided into two parts - Spermatogenesis and Oogenesis. Spermatogenesis is the formation of sperms and Oogenesis is the formation of egg or ova.
Spermatogenesis is the process of formation of  sperms. A sperm is haploid and the cells from where it develops are diploid, so the process of formation of sperms need to pass through number of stages.The process of sperm formation starts when a boy reaches his puberty, generally around 15 years of age.
 The stages can be divided as follows:
1) Multiplication Phase
2)Growth Phase
3)Maturation Phase
4) Formation of Spermatozoa







In Multiplicative phase, the cells that are present in the seminiferous tubule under go division. This division is mitotic division and helps in increasing the number of cells without undergoing reduction in the constituents of the cell. It is Mitosis division. The male germ cells are also called as Spermatogonia.

After the multiplicative phase occurs the growth phase. Here in this phase Spermatogonia start growing. It accumulates huge amount of cytoplasm, DNA undergo replication and its size increases. They are now referred to as primary spermatocytes. The growth phase is also called as spermatocytogenesis. 









Next phase is the maturation phase, in this phase the spermatocytes undergo division. This division is meiotic division. Meiotic division is a reduction  division as from diploid condition the cells become haploid. Here from 23pairs of chromosome ie 46 number of chromosomes  become 23, so haploid. This leads to the formation of Spermatids.
Spermatids finally get transformed into spermatozoa. This process of formation of spermatozoa from spermatids is called Spermiogenesis.


Monday, June 21, 2021

MENSTRUAL CYCLE:



 MENSTRUAL CYCLE: The gametes formation in females takes about 28 days( it varies from female to female but average taken to be 28 days).In this cycle, rhythmic changes occur in the reproductive organ of female primates ( Monkeys, apes and human being). The first menstruation begins at puberty   ( on set of reproductive phase, in female it generally starts from the age of 12 years) and it is called menarche. Human female's fertility period extend from around 12 years to Menopause at about 45 - 50 years. Menopause is the term given when in woman's life ovulation and menstruation stops. During the reproductive period say from around 12 years to around 45 - 50 years , generally one egg is released every 28 days or so alternately from two ovaries. In female there is the occurrence of one pair of ovary - right and left ovary. Suppose if in the first  menstrual cycle, right ovary produces the egg than left ovary at that moment remains silent and in the next  menstrual cycle left ovary will release the egg where as the right ovary remains silent. Generally female remain fertile for around 32 years and about 13 eggs mature each year.

The menstrual cycle in human being lasts 28 days. The days are numbered from the first day of the blood flow in the menstrual period. So these cycle events from the first day is called the Menstrual cycle The menstrual cycle in humane female is divided into three phases: 

 1)Follicular or Proliferating Phase 

 2)Luteal or Secretory Phase

 3)Menstrual or Bleeding Phase

In all these above phases Endometrium layer lining the uterus develops, Huge number of hormone secretion occurs, Ovary becomes ready to release an  egg and if the egg is not fertilised then the endometrium starts breaking down.  





Thursday, June 17, 2021

PATH FINDER

 

SUNIRAM ENGTI: This is a true and inspiring story of a young boy who in the midst of all hurdles and constraints emerged as the real world challenger. Suniram Engti , an alumni of Vivekananda Kendra Vidyalaya (NEEPCO), Umrangso (Passed his XII Arts in 2016) now not only confines within Umrangso or Dima Hasao district of Assam but also known very well in different parts of the world among the Karate circles. As a teacher of Vivekananda Kendra Viyalaya ( NEEPCO), Umrangso it gives me immense pleasure , happiness and pride to find his name labelled with the greatest Karatekas of the globe. This is not because he is bringing medals for India but there is another part linked with it and I need to touch upon  that.


                                                                               

Suniram Engti is the eldest son of  Jongdang  Engti and Kajir Rongpipi. His father Jongdang Engti is the gardener of our Vidyalaya.

Geographically, economically and from other aspects, Dima Hasao is remote and less developed than other parts of Assam; and when we come to Umrangso it is rated much lower than Haflong in DimaHasao district. Road conditions linking Umrangso with Guwahati, Shillong and Silchar always remain in woeful condition; making it even poorer. But Suniram’s resident is not in Umrangso it is around 8 Km away from VKV(NEEPCO), Umrangso - in a village called Boralonglai. Condition of the villagers is generally in “Hand To Mouth Existence” and only a counted few are serving as Grade D employee in some organisations. Educational awareness is lacking among the villagers as their primary and only need remains procurement of food.


I have seen Suniram from his infancy. Walking a long distance of  8 Km  to the school and return home after school was his regular phenomenon. By the time Suniram reached his senior secondary classes, he used to take 30min to cover the hilly road of 8 Km to reach school. So I believe these were the building blocks which materialized later on to make him strong. His daily routine was filled with other things like ploughing, farming and selling the agricultural produce in the market.These I would like to put in the first place of the ladder that helped him secure medals.




Those days, during his schooling; Karate was introduced as a co-curriculum subject. Karate classes did not continue for more than 3 years but those classes created an impression in the child Suniram’s mind. Every morning he used to get up early and practised Karate – Kata, Kick, Yoga for long hours. As it remained a continued process for him and eventually his lickings, Hobby got converted to aim and goal in life. The boy understood the financial constraints of his family and the locality and that may be the another reason which I believe made him stronger and determined to do something big for his family in specific  and locality in general. So, these I would like to put in the second place of the ladder that helped him secure medals.


As a student, Suniram was a mediocre, very obedient and down to earth . His words were very gentle and he had utmost respect towards his teachers. This I believe is above all, the most important ingredient to achieve success in life. His teachers’ blessings and good wishes always worked silently for him.


Later on,  Suniram took more hardship to develop himself in the field of Karate. Presently he is holding Karate Black Belt 2nd Dan.  His instructors are  Md. Siraj Ahmed from India( National Chief Instructor) and Soke Fukuda Hirotaka , Chief Instructor  Japan. Presently Suniram is appointed as  N.E. INDIA chief instructor


A  Glimpse of his Achievements:

1)     In 2012 he represented Vivekananda Kendra Vidyalaya(NEEPCO) Umrangso and secured Bronze medal in All India Karate Championship , which was held in Tezpur Assam .


2)       28TH April 2019 , won Bronze Medal  in South Asian Karate Championship held  in New Delhi.


3)     From 23rd to 26th August 2019, participated in Kumite(fight) in World Karate Championship which was held in Tokyo, Japan. There he was adjourned as the Best Discipline Fighting Award.


4)      From 5th to 10th October 2019, he participated  in the International Karate Championship  which was held in Kula Lumpur, Malaysia. He secured there real GOLD MEDAL by defeating Philippine in 2:3 points.


5)      He got selection for World Karate Championship , 2020. The event was supposed to be held from July 10th 2020 in FLORIDA , USA but it was cancelled because of corona pandemic.


So this Umrangso boy needs every body’s motivation and wishes to fly our tri colour in foreign land. Hope, he might bring more laurels for our motherland in the near future.

 

 

By - Santanu Nandi Purkayastha

 



SICKEL CELL ANAEMIA

 Sickle Cell Anaemia : Sickle cell anaemia is an autosome linked recessive disease. Here in this disease both male and female can become diseased or both may be carrier depending upon the presence of  infected gene/s .Here in this context we need to know two words homozygous and heterozygous. Homozygous individual are those when two  chromosomes have the infected gene ie. HbS and HbS and in case of Hetrozygous individual their two chromosomes are arranged as HbS and HbN.                                           Here HbS is characterised by sickle condition and HbN is normal. 





Human blood cells are Biconcave disc shape, which maximises the surface area of the cell membrane for oxygen . But in case of sickle cell Anaemia cell take the shape of a Sickle and it become difficult for the blood capillaries to transport those cells. In such condition the person suffers from oxygen tension. Genetically it is a point mutation where a change of single base pair in the gene for beta globin chain that results in the change of amino acid residue glutamate to valine.



Wednesday, June 16, 2021

HAEMOPHILIA

 Haemophilia: Haemophilia is a genetical disease. Expression of this disease occurs in Male while female remain as carrier. This is because human being has one pair of sex chromosome and in that pair it may comprise XY  or XX chromosome and if it is XY then it is Male in Humans and if it is XX then it is Female in Humans. Haemophilia is a sex linked recessive disease. It is due to the recessive gene on X chromosome. In case of human female there is the occurrence of two X chromosome, so if in one of the X chromosome the gene for haemophilia is there, than in female there is the occurrence of another X which gives its expression. But in case of Male there is the occurrence of one X chromosome and if that X chromosome has the gene for Haemophilia than the expression of Haemophilia occurs in the male. Therefore, females are carrier and if males have the gene then they are infected and diseased. 



In this disease , a single protein that is part of the cascade of proteins involved in the clotting of blood is affected. Due to this, if there is a minor cut then blood keep on coming out. The disease is therefore transmitted to a son from a carrier mother. It is also known by another name as Bleeding disease or Royal Disease. Royal Disease named because males of Queen Victoria in different generations suffered from this disease.  




Tuesday, June 15, 2021

SILK EXTRACTION FROM ERI SILK WORM TO HANDLOOM PRODUCTION

 

Traditionally Eri silk comes from the caterpillar Samia ricinin , found  in the North Eastern part of India , specially in the Dima Hasao district of Assam . The woolly white  silk is often referred  to as  Fabric of Peace” as it is processed without killing the silk worm. The heavy rainfall and humid environmental conditions  in Umrangso encourages the growth of Eri silk worm.

 Silk is extracted from eri silkworm. People in and around Umrangso (Dt- Dima Hasao, Assam ) are engaged in the production of silk traditionally. For that they construct  a thatched house where they keep the leaves of castor plants. In this leaves  moth of eri worm lays eggs and the leaves are also used as food by them. After few days  eggs develop into larva. The next stage is the pupa, in this stage it gives out fiber from its mouth which surrounds the complete caterpillar and that becomes cocoon . Then the  cultivator cut a portion of the cocoon  and take out the worm or they may put it in the hot water from where thread is extracted. But  in case of Umrangso  cultivators are found to cut the portion of cocoon and take out the worms, which is again kept for future use.


A female silk moth  lays hundred of eggs at a time. The eggs are stored carefully  on strips of cloth or paper and sold to silkworm farmers. The farmers keep the eggs under hygienic conditions of temperature and humidity. The eggs are warmed for a suitable temperature  for the larva to hatch from eggs. This is done when mulberry  tree develops fresh leaves. The larvae which is also called as caterpillar eat day and night and develops its size enormously. The larvae are kept in clean bamboo trays along with the leaves of mulberry. After 25 to 30 days the caterpillars stop eating  and move to a tiny chamber of bamboo  in tray to spin cocoons . The caterpillar or silk worm spin the cocoon inside which develops rearing and reeling . After completing this, I went for the  next part regarding the procedure employed for handloom production from silk fibre.

I have taken 3 to 4 places of Umrangso  for the survey and better information. People in this area have a sound traditional knowledge in silk production but it need to be blended with the scientific knowledge. As the people of this region is not getting a good market to sell their finished products so they are reluctant to devote huge time. Moreover seeds are also very costly to start the livelihood.

 

Some steps from my end I have taken to popularise the hand loom production for our locality which  can also be viewed in broader aspect. Kindly view the video of self made taat sahl.




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MEDICINAL PLANT - TRICLISIA sp.

 Medicinal Plant - Triclisia species: Triclisia sp. in Dimasa language is called Duser plant. It is slender woody liane which is found extensively in Dima Hasao district of Assam, specially in Umrangso. From the time immemorial people are woody vines to cure their disease. When I have conducted survey here with my students then number of things came to light. The people of this area use the water extract of the plant to cure the diseases like- Jaundice , Malaria etc. Moreover water extract of the Duser plant has high quantity of minerals and that helps in keeping them physically fit.





 

The tree generally grows in dense forest area of the region, they are liane means they are rooted in the soil but the woody stem take vertical support of woody plants to encircle around it.The villagers cut the woody vine twice. First cutting in the selected portion and the second cutting is given around one hand above the first cutting and water rushes out very fast (generally in summer) which can fill bottle easily. The water extract is then collected and used for curing many disease like - Jaundice , Malaria and any other liver related ailments. Till date there is no medicine against Jaundice but the people of this locality are using water extract of the plant is found to be successful. These water activates the liver and help the person to become healthy within a short period of time.




Other benefits found from the water extract are as follows-

1) The water is very cold and people consume it in water scarcity hills regions of Dima Hasao , Assam.

2) The water also helps in curing eye infection




Monday, June 14, 2021

NATURAL CURE: ALUMIKRI PLANT (Begonia roxburghii A.DC)

 

  NATURAL CURE:  ALUMIKRI  PLANT (Begonia roxburghii A.DC).

 

Dima Hasao is one the most naturally beautiful district of Assam. People of this district practice herbs and leaves of the plants for the treatment of their diseases . The reason is that the medical centre is very far away from the basti and villages and people are relatively very poor but the traditional values and the knowledge about the plant that has been passed to them by their forefather is commendable. Out of many herbs , leaves , barks and trees they use for the treatment , I have selected right now Alumikri plant.



Alumikri plant’s scientific name is Begonia roxburghii  A.D.C and belongs to the family Begoniaceae. It  is very much widely distributed in the DimaHasao District of Assam and specifically found extensively in Umrangso. The plant grows well in the moist and shady places and generally they flourish near the bank of the river or sides of a canal where it is where it is moist, rainy and shady. Every part of the plant is very important for the villagers. Alumikri is the house hold name in the district and it is considered to be very sacred. Any ailment related to stomach when occurs among the villagers then Alumikri has the answer for it. Different types of ailment of the stomach like severe stomach pain, Loose Motion, Dysentery and Diarrhea then the people of this region consumes tuber of Alumikri  and within a short period of time they regain their previous health.



Plant generally attains a height of about one  feet . The plant has a  tuber and that tuber has a high medicinal property. People takes out a very little portion of the tuber from the plant and grind it with little amount of water . After grinding properly it is mixed with little bit more water and then filtered. After the filtration they keep the filtrate and throw away the residue and with the filtrate they cure different types of ailment related to stomach.



Other than that of medicinal value the plant also finds a place among the people of Dima Hasao as vegetable. The leaves are sour in taste and have many recopies                  for its curry preparation. The plant leaves has high accumulation of minerals and nutrients in it. And inclusion of this plant in their diet keeps the villagers away from diseases.

The stem of the plant has huge water store in it , so when people go for tracking they eat the stem to get warter. Plants also bears red fruits which are also eaten by the people

Medicinal Dose  : At first small portion of Alumikri plant’s tuber is made paste with little bit of water, then it is filtered and filtrate is taken. In the filtrate 100ml of water is mixed and the mixture become ready to be used as medicine. Generally villagers take two spoonful of the prepared mixture in the morning as well as in evening.

This  plant can also be grown in villagers houses in pot. For that we have to keep the plant in shady places and regularly give needed dose of water.





BY- Santanu Nandi Purkayastha

Sunday, June 13, 2021

REPRODUCTION IN PLANTS

 Reproduction in Plants : Reproduction in plants can be divided into two main parts, one is Asexual and other is Sexual. In case of Asexual reproduction one parent is sufficient to produce an organism. In case of Asexual reproduction there is no gamete formation or neither zygote is formed. But in case of Sexual reproduction there is the need of two parents. Each of the parent produces a gamete and two gametes from two parents unite together to form zygote. Zygote later on forms the organism. In case of Sexual reproduction as two parents are involved so there is the occurrence of variation in the next generation or off spring. But in case of Asexual reproduction as one parent take part in the formation of an organism so there variation does not takes place.Variation plays a great role in evolution











PHOTOSYNTHESIS

 PHOTOSYNTHESIS:Photosynthesis is a process by which a plant prepares its food in presence of sunlight. For this process plant needs carbon dioxide and water which comes from air and soil respectively. The process occurs in the chlorophyll of the leaves. Product of the photosynthesis is carbohydrates and it gives out oxygen.







STOMATA

 STOMATA: Stomata are minute pores present on the surface of the leaves.Generally the number of stomata are more on the lower surface than on the upper surface. Stomata helps in the exchange of gases and transpiration. Plants perform photosynthesis by taking carbon dioxide through stomata and gives out oxygen in this process through the stomata. In respiration plants takes oxygen through stomata. Excess amount of water from the plant body is also given out through stomata, this is called transpiration.

Guard cells are present around the stomata.


HEREDITY

Heredity is the transmission of characters from one generation to another. In sexually reproducing organism there is the need of two pare...