मानव मे पोषण भाग 1 - जैव प्रक्रम – Nutrition in Humans - Life Processes - Class 10 Biology

NEET 2020 - Revision In 60 Days | Class 12 Human Health And Disease Part - 1 | NEET Biology

NEET 2020 - Revision In 60 Days | Class 12 Mineral Nutrition Part - 1 | NEET Biology

Class 10 Science| Chapter 6 Life Processes | Important Questions | Revision | Part-1

Class 10 Science| Chapter 6 Life Processes | Important Questions | Revision | Part-2

In this section each item consists of six sentences of a passage. The first and the sixth sentences are given in the beginning as S1 and 56. The middle four sentences in each have been jumbled up and labelled as P, Q, R and S. You are required to find out the proper sequence of the four sentences and mark your response accordingly on Answer Sheet. S1: For several million years, humans lived by hunting wild animals and gathering wild plants. S6 : As a result, conditions were favourable for the growth of grasses such as wild barley and wheat. P: This led to the development of farming and pastoralism as a way of life. Q : This change took place because the last ice age came to an end about 13,000 years ago and with that warmer, wetter conditions prevailed. R: Then, between 10,000 and 4,500 years ago, people in different parts of the world learnt to domesticate certain plants and animals. S: The shift from foraging to farming was a major turning point in the human history. The correct sequence should be

Human blood has a narrow Ph range of 7.3-7.4 , which must be maintained for methabolic processes to function properly. To keep the Ph in this range requires a delicate balance between the concentration of the conjugate acid-base pairs making upto the buffer system. The main buffer is a carbonic acid/ hydrogencarbonate system, which involves the following three equilibria. CO_(2)(g)hArrCO_(2)(aq) CO_(2)(aq)+H_(2)O(l)hArrH_(2)CO_(3)(aq) H_(2)CO(aq)+H_(2)O(l)hArrHCO_(3)^(-)(aq)+H_(3)O^(+)(aq) Carbonic acid (H_(2)CO_(3)) is a weak acid and HCO_(3)^(-) (aq) is its conjugate base. At the temperature of the human body, the pK_(a) for carbonic acid is 6.4 However, the normal concentration of CO_(2)(g) in the lungs maintanis a ratio of HCO_(3)^(-)(aq)//H_(2)CO_(3)(aq) in blood plasma of about 8:1 . The carbonic acid concentration in the bloos is largely controlled by breathing and respiration. Hydrogencarbonate ion concentration is largely controlled by excreation in urine. If blood pH rises above 7.4 , a potentially life-threatening conditon called alkalosis can result. This can happen in patients who are hyperventilating from severse anxiety, or in climbers suffereing from oxygen deficency at high altitude. (Given: log 2=0.3) Calculate pH of blood at the temperature of the human body.

Human blood has a narrow Ph range of 7.3-7.4 , which must be maintained for methabolic processes to function properly. To keep the Ph in this range requires a delicate balance between the concentration of the conjugate acid-base pairs making upto the buffer system. The main buffer is a carbonic acid/ hydrogencarbonate system, which involves the following three equilibria. CO_(2)(g)hArrCO_(2)(aq) CO_(2)(aq)+H_(2)O(l)hArrH_(2)CO_(3)(aq) H_(2)CO(aq)+H_(2)O(l)hArrHCO_(3)^(-)(aq)+H_(3)O^(+)(aq) Carbonic acid (H_(2)CO_(3)) is a weak acid and HCO_(3)^(-) (aq) is its conjugate base. At the temperature of the human body, the pK_(a) for carbonic acid is 6.4 However, the normal concentration of CO_(2)(g) in the lungs maintanis a ratio of HCO_(3)^(-)(aq)//H_(2)CO_(3)(aq) in blood plasma of about 8:1 . The carbonic acid concentration in the bloos is largely controlled by breathing and respiration. Hydrogencarbonate ion concentration is largely controlled by excreation in urine. If blood pH rises above 7.4 , a potentially life-threatening conditon called alkalosis can result. This can happen in patients who are hyperventilating from severse anxiety, or in climbers suffereing from oxygen deficency at high altitude. (Given: log 2=0.3) Calculate the maximum permissible value of ([H_(2)CO_(3)])/([HCO_(3)^(-)]) in the human blood to just prevent alkalosis.

Class 12 Biology | Chapter 10 | Microbes in Human Welfare | Important Questions and Quick Revision