Your science board exam is on March 28. Will you be asked about sustainable development or is it about the largest cell in the human body?
Well, this was one of the questions asked by stressed students during a live chat with Topper Biology Expert Deepika Chaudhary on March 27.
Here are the answers to these questions and more!
Siddhant: Hello maam, what is the need for multicellular organisms to have chemical coordination within the cell?
Deepika Chaudhary: It's a method of control and coordination in these organisms.
Samsan: Mam, what is the difference between speciation and evolution? How are they linked?
Deepika Chaudhary: Speciation is a part of evolutionary process. For more details refer to solved board exam papers.
Swati: Can u pls tell me how to answer this question How is the increase in demand for energy affecting our environment adversely?(for 1 mark)
Deepika Chaudhary: As energy demand increases, more and more natural resources are exploited. Also, the combustion of these fuels produces toxic gases that pollute the environment.
Sauhard: Suggest some approaches towards the conservation of forests.
Deepika Chaudhary: 1. Participation by local people 2. Establishing protected areas like natural parks etc. For indepth knowlege refer to study online.
Samsan: Mam, how does gene frequency in a population change? Give three ways.
Deepika Chaudhary: Genetic drift, geographical isolation, reproductive isolation. For more details you can refer to mock papers, exam cracker.
Sauhard: What are the various factors on which sustainable development depends?
Deepika Chaudhary: It depends on people's participation and government organisations.
Samsan: Mam what is double fertilisation?
Deepika Chaudhary: The union in flowering plants of 2 sperm nuclei. One sperm nucleus unites with the egg to form the diploid zygote, from which the embryo develops, and the other unites with two polar nuclei to form the triploid, primary endosperm nucleus. Watch these exam special videos.
Samsan: Please give two factors on which rate of photosynthesis depends?
Deepika Chaudhary: It depends on: Intensity of light amount of carbon dioxide.
Mohit: What are genotypic and monotypic ratios?
Deepika Chaudhary: Genotype is the genetic makeup of an organism. Monohybrid ratio is the ratio of different genotype or phenotype obtained in the filial 2 generation of a monohybrid cross.
Gurman: What is an allele?
Deepika Chaudhary: Allele is one member of a pair or series of different forms of a gene. Usually alleles are coding sequences, but sometimes the term is used to refer to a non-coding sequence. You can also check these mock papers and solved board exam papers.
Siddhant: How is sucose translocated in plants?
Deepika Chaudhary: Through the vascular tissue called phloem. For better understanding watch these exam special videos.
Srs.sep20: Describe the mechanism of breathing and how is breathing different from respiration?
Deepika Chaudhary: Breathing is the physical process of exchanging gases with the surrounding environment. On the other hand respiration is a broader term that includes both breathing and cellular respiration.
Gurman: The diagram of nephron on topper and that given in the NCERT are not the same. I find the topper one easier. Can I draw that?
Deepika Chaudhary: Yes. You can also check last minute revision kit.
Gurman: Please define Heredity, Variation, Species,Genetics and Speciation.
Deepika Chaudhary: Heredity is the process of passing of traits to from parents to offspring Variation: It is the variation in alleles of a gene. Species: A group of organisms capable of interbreeding and producing fertile offspring. Speciation : It is the process by which new species originate. Genetics: it is the study of heredity and variation in living organisms.
Siddhant: What is tissue culture? Explain.
Deepika Chaudhary: Tissue culture is the growth of tissues and/or cells separate from the organism. This is typically facilitated via use of a liquid, semi-solid, or solid growth media, such as broth or agar. Tissue culture commonly refers to the culture of animal cells and tissues, while the more specific term plant tissue culture is used for plants.
Swati: How can we say that hydrogen is a cleaner fuel as compare to CNG?
Deepika Chaudhary: Hi Swati, burning of hydrogen results in water as product whih is non pulluting. On the other hand combustion of CNG results in carbon dioxide besides some hydrocarbons as by products. These by products are polluting & subsequently lead to global warming. Best wishes. Watch these exam special videos for clarity in your topic.
Swati: The largest cell in the human body?
Deepika Chaudhary: The largest cell in the human body is the ovum, the female sex cell. The ovum is about 1000 micrometers, or one millimeter, in diameter.
Sauhard: Do we have to also draw renal vein,aorta and renal artery in excretion diagram.
Deepika Chaudhary: Yes, because it's mentioned in the NCERT textbook.
Chikky: Hello mam, i want to know what the function of liver is.
Deepika Chaudhary: Liver secretes bile juice that helps in digestion of fats.
Swati: The information source of making proteins in the cell?
Deepika Chaudhary: Its the sequence of nucleotide in the DNA. Check study online.
Sauhard: What are the two functions of lymph?
Deepika Chaudhary: 1. It carries digested and absorbed fat from intestine. 2. It drains excess fluid from the extra-cellular space into the blood.
srs.sep20: Ma'am, cud u please explain what is monohybrid and dihybrid ratio in simple terms
Deepika Chaudhary: Monohybrid cross: The parents differ at only one gene locus. Dihybrid cross: The parents differ at only two gene loci.
Siddhant: What is the function of septum?
Deepika Chaudhary: Septum is a partition that separates right and left sides of heart. Solve these previous year board exam paper.
Siddhant: Maam, please explain the process of double circulation?
Deepika Chaudhary: The double circulatory system of blood flow refers to the separate systems of pulmonary circulation and the systemic circulation in mammals and birds. So, basically blood flows twice through the heart in each cycle.
Samsan: Hello mam, can you tell me what gene frequency is?
Deepika Chaudhary: It is the frequency of occurrence of an allele in relation to that of other alleles of the same gene in a particular population.
Gurman: Mam, Do we have to study about double fertilization in plants?
Deepika Chaudhary: Yes. Please refer to these mock papers.
Gurman: Are we supposed to study well the boxes (more to know) as in about dialysis and blood pressure?
Deepika Chaudhary: It's actually additional information. These concepts will not be asked in CBSE exams. Check study online.
Sauhard: What are check dams?and also tell how were they useful
Deepika Chaudhary: Check-dams are basically small barriers built across the direction of water flow on shallow rivers and streams. They are useful for water harvesting.
Swati: Only variations that confer an advantage to an individual organism will survive in a population.Is it? Why or why not??
Deepika Chaudhary: This is not always the case. Sometimes due to chance factor, variations that are not advantageous survive. This happens in case of genetic drift. Check these last minute revison kit.
Swati: Which blood group is dominant A,B,O or AB or some other
Deepika Chaudhary: A B O blood group system is an example of co-dominant traits. In this case A and B genotype are co-dominant while O is recessive. So, if A and B are present together, both will express themselves. Solve mock papers, solved board exam papers.
Sauhard: Do we have to prepare the diagram of heart and brain also?
Deepika Chaudhary: Yes if the question demands a digram then you should. You can refer to these hand-drawn diagrams.
Ankita: Can u please explain the meaning of xylum?
Deepika Chaudhary: Xylem is a vascular tissue present in plants.
Archana Pandey: Can u plz explain the meaning of xylum?
Deepika Chaudhary: Xylum is the vascular tissue in plants that transports water and minerals.
Swati: Dear ma'am, could u pls tell me how to define pollination and fertilisation
Deepika Chaudhary: Pollination: It is the transfer of pollen from the stamen to the stigma. Fertilization: It is the process of combining or fusing the male gamete with the female gamete to form zygote. Watch these exam special videos.
Sauhard: Hello mam, please explain how speciation may take place?
Deepika Chaudhary: Speciation usually takes place when two sub-populations of a particular species are geographically isolated and there is no gene flow between them. All the best!
