भारत में मिला घोंसले बनाने वाला मेंढक September 4, 2009

भारत के एक वैज्ञानिक ने मेंढकों की तीन ऐसी दुर्लभ प्रजातियाँ ढूँढने का दावा किया है जो अपने अंडे देने के लिए घोंसले बनाते हैं.

मेंढक की ये प्रजातियां केरल और कर्नाटक की पश्चिमी पहाड़ी श्रंखलाओं के जंगलों में पाई जाती है जहाँ ख़ूब बारिश होती है.

दिल्ली विश्वविद्यालय के डॉक्टर एसडी बीजू का कहना है कि ये छोटे-छोटे मेंढक 12 सेंटीमीटर तक लंबे होते हैं. ये मेंढक अंडे देने के बाद उन्हें गर्मी, शिकारी पक्षियों और कीड़ों से बचाने के लिए घोंसले बनाते हैं.

ये मेंढक पत्तियों को ऊपर से नीचे तक इस तरह से मोड़ते हैं कि उससे अंडे रखने के लिए एक घोंसला बन जाता है और किसी चिपचिपे पदार्थ से उसे मज़बूत भी बना देते हैं ताकि अंडे बाहर ना निकल सकें.

डॉक्टर बीजू का कहना था, “ये दुर्लभ प्रजाति के मेंढक हैं और एशिया भर में सिर्फ़ यहीं पाए जाते हैं.”

वैज्ञानिक को दुर्लभ प्रजाति के इन मेंढकों का पता 20 वर्ष के शोध के बाद चला है. यह शोध उन्होंने केरल के वायनाड क्षेत्रों और कर्नाटक के कूर्ग क्षेत्र में किया.

डॉक्टर बीजू का कहना था कि मेंढकों की यह प्रजाति अमरीका और अफ्रीका में पाई जाने वाली उस प्रजाति से भिन्न हैं जो पत्तियों का घोंसला बनाती है क्योंकि उस प्रजाति के मेंढक तब घोंसले बनाते हैं जब उनकी मादाएँ अंडे देती हैं.

डॉक्टर बीजू के अनुसार अमरीका और अफ्रीका में पाई जाने वाली प्रजातियों के मेंढक अंडे देते समय ही घोंसले बनाते हैं जबकि यह काम नर और मादा दोनों साथ मिलकर करते हैं जबकि कॉफ़ी और अन्य तरह के वृक्षों की भरमार होने से इस भारतीय प्रजाति के मेंढकों पर लुप्त होने का ख़तरा मंडराने लगा है.

डॉक्टर बीजू कहते हैं, “आठ वर्ष पहले जब मैंने उस क्षेत्र का दौरा किया था तो ऐसे मेंढकों को रात में ढूँढ पाना आसान था लेकिन हाल के समय में तो नाटकीय बदलाव आया है और अब इस प्रजाति के मेंढकों को ढूँढ पाना बेहद मुश्किल है.“

DISCOVERIES September 3, 2009

PART OF CELL	DISCOVERED BY
CELL	R.HOOK
NEUCLEUS	R.BROWN
LIVING CELL	LEEWENHOKE
PLASSMA MEMBRANE	R.BROWN
RIBOSOME	PLADE
GOLGI APPRATUS	CAMMILO GOLGI
MITOCHONDRIA	KOLLIKER
CELL WALL	R.HOOK
PROTOPLASM	DUDARJIN
LYSOSYME	CD DUVE
CELL THEORY	SCHELDIAN &SCHWAN
CHROMOSOME	MISCHER
ENDOPLASMIC RETICULUM	PORTER

Biowatch September 3, 2009

GOLGI COMPLEX IT IS FOUND IN ALL EUKARYOTIC CELLS EXCEPT RBC COMPOSED OF PROTEIN LIPIDS & POLYSACCHRIDE ITS MAIN FUNCTION IS CELL SECREATION IT TRANSPORT CERTAIN MATERIAL LIKE PROTEIN & POLY SCCHRIDE IT IS SIMILER IN BOTH PLANT AND ANIMAL CELL IT INVOLVE FORMATION OF LYSOSYME IN PLANT CELLS IT IS CALLED DICTYOSOMES PLASTIDS THESE GENERALLY PIGMENTS & MAY SYNTHESIZED AND ACCUMULATE VARIOUS SUBSTANCE THEY ARE OF THREE TYPES –LEUCOPLAST ,CHROMOPLAST,CHLOROPLAST HOW EVER SOME PLASTIDS ARE DEVOID OF PIGMENT AND THERE FUNCTION IS STORAGE OF MATERIAL THEY R CALLED LEUCOPLAST LECUOPLAST ARE FOUND IN PART OF PLANT WHERE NO LIGH T IS AVAILABLE CHLOROPALST ARE GREEN IN IN COLOUR AND MOST COMMAN THEY HELP IN PHOTOSYNTHESIS CHROMOPLAST ARE VARIOUS COLOURED FOUND IN PETAL ROOT AND FRUITS RED COLOUR OF TOMATO IS DUE TO THEM MITOCHONDRIA THESE R THE SEAT FOR CELLULAR RESPIRATION AND PRODUCE ENERGY THEY ARE REGARDDED AS POWER HOUSE OF CELL ATP SYNTHESIS TAKES PLACE IN MITOCHONDRIA IN LIVER CELL THERE ARE NEAR ABOUT 1400 MITTOCHONDRIA PER CELL THESE ARE COMPOSED OF PROTEIN LIPIDS & A LITTLE AMOUNT OF RNA 40 PERCENT OF ITS COMPOSITION IS ENZYME NO OF MITOCHONDRIA IN PLANT IS LESSER THEN HUMAN AS ATP SYNTHESIS ALSO TAKE PLACE IN CHLOROPLAST CRIESTE IS ITS PART IT HAS F0-F1 COMPLEX KREB CYCLE TRAKES PLACE IN IT LYSOSYME THEY ARE OF FOUR TYPE PRIMARY SECONDRY TATRTARY & RESIDUAL BODY THERE FUNCTION IS TO DISSOLVE SME MATERIAL AND BREAK IT INTO PARTS SO IT HELP IN INFECTION DIGESTION PRIMARY LYSOSOME ARE THAT WHICH IS RECENTLY PRODUCED AND NOT YET USED EVEN SECONDRY LYSOZYME IS THAT WHICH IS JUST STARTED USING RESIDUAL BODIES ARE THAT WHO’S ALL THE ENZYME ARE USED AND IS NOW A WASTE SPHEROSOMES THESE FUNCTION FOR STORAGE OF MATERIAL LIKE LIPID NEUCLEUS o MOSTLY IT IS LOCATED AT CENTER OF CELL o BOUNDED BY DOUBLE MEMBRANE o IT CONTAIN GENETIC MATERIAL SO CONTROL THE WHOLE BODY o ITS COVERING NEUCLEAR MEMBRANE HAS PORES THROUGH WHICH IT COMMUNICATE WITH REST OF CELL o IT HAS NEOCLEOLUS OR AND CHROMTIN o IT MAY BE ONE OR MORE IN NUMBER o IT HAS DNA OR RNA WHICH CAUSES ITS REPLICATION

colour blindness August 17, 2009

The Genetics of Colour Blindness

The first human genetic trait to be identified and linked to a specific chromosome was colour blindness.

Through my research I have discovered that one pair of chromosomes is involved in the determination of sex– the XX chromosomes of the female and XY hromosomes of the male. The traits determined by the genes carried in the X chromosomes will show a special kind of inheritance, called sex-linked inheritance. One of the traits in question is colour blindness, a condition in which a person is unable to distinguish colours, particularly red and green, easily distinguished by a person with normal vision.

Colour blindness is a recessive trait with respect to normal vision, which is the dominant trait. I will identify the gene for normal vision as C and the gene for colour blindness as c. Consider now a marriage in which the mother is colour-blind and the father has normal vision. The colour-blind mother carries two X chromosomes, both with color blind (c) genes, and all the eggs she produces will also carry c. The father, with normal vision, has an X chromosome with normal colour (C) gene, and a Y chromosome that does not carry a gene for colour vision at all. Half of his sperm will have an X chromosome and the other half will have a Y chromosome.

The X-bearing sperm fertilizing the egg cells will give rise to daughters, who will carry one X chromosome with C and another with c gene: that is Cc. Since normal vision is dominant over colour blindness, these girls will have normal vision, but will harbor the gene for colour blindness, c.

If such a woman is married to a normal man (C), all of the daughters will have normal vision; but half of them will harbor the gene for colour blindness. Half of all the sons will inherit the X chromosome with the gene for colour blindness from their mother, and will consequently be colour-blind (c); the other half of the male offspring will inherit the gene for normal vision (C).

A colour-blind man (c) married to a normal woman not carrying the gene for colour blindness (CC) produces children with normal vision only. But while his sons (C) are free from the gene for colour blindness, all his daughters carry this gene in a hidden condition (Cc) and will transmit it to half of their children.

The punnett square is a device (chart) used to predict the probability of offspring having certain genetic characteristics. I will now use the punnett square to further explore the probability as it relates to colour blindness. A normal colour vision man is identified by XC Y.

A normal colour vision women who carries the gene for colour blindness is
identified by XC Xc.

	XC	Y
XC	XC XC	XC Y
Xc	XC Xc	Xc Y

A colour-blind man is identified by Xc Y.
A normal colour vision women who carries the gene for colour blindness is
identified by XC Xc.

	Xc	Y
XC	XC Xc	XC Y
Xc	Xc Xc	Xc Y

A colour-blind man is identified by Xc Y.
A colour-blind women is identified by Xc Xc.

	Xc	Y
Xc	Xc Xc	Xc Y
Xc	Xc Xc	Xc Y

This is a very rare occurrence.

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What is The Kea August 15, 2009

Dubbed “the clown of the mountains,” the Kea is an unusual species of parrot found on the South Island of New Zealand. Regarded as a pest by residents and an attraction by tourists, the Kea is known for its curious and playful character and can often be observed flying off with human possessions. About the size of a crow, the Kea is an omnivore that typically feeds on plants, insects, and other birds. Now uncommon, it was once killed for bounty due to its habit of preying on what large mammals