Khoảng 75-80% sự chậm phát triển trí não là do di truyền, và 20-25% còn lại là do những nguyên nhân bên trong cơ thể như sự bất thường ở các nhiễn sắc thể hay chấn thương ở não. Sự chậm phát triển trí tuệ từ nhẹ đến vừa có thể có nguyên nhân là do sự rối loạn của một gene cho đến nhiều nhiễm sắc thể bất thường, có thể bao gồm hiện tượng mất đoạn nhiễm sắc thể. Theo như nhiên cứu trên những cặp sinh đôi, sự kém phát triển trí tuệ từ vừa đến nặng là kh

What is the pH of the medium when molasses is used as substrate for the production of citric acid? A. 3 B. 4 C. 5 D. 6 Which of the following nitrogen sources is added in the fermentation medium of citric acid production? A. Ammonium salt B. Urea C. Both (a) and (b) D. Peptone... In submerged process for the fermentation to produce citric acid, A. A. niger is used with solid substrate as sweet potato B. A. niger floats on the surface of solution C. Fungal mycelium grows through out the solution in a deep tank D. both (a) and (b) Which substrate is used in the fermentation of citric acid? A. Beet molasses B. Sucrose C. Starch hydrolysate D. All of these...

To maintain aseptic conditions during fermentation which of the following is needed? A. Sterilization of fermentor B. Sterilization of air supply C. Aeration and agitation D. All of these... View Answer Workspace Report Discuss in Forum High ethanol concentration A. promotes yeast growth B. inhibits yeast growth C. promotes bacterial growth D. inhibits bacterial growth.... What are the fermentation conditions for the ethanol production? A. pH 6; temperature 35°C B. pH 5; temperature 35°C C. pH 6; temperature 30°C D. pH 5; temperature 30°C...

Candida utilis is used for the fermentation of waste sulphate liquor since it ferments A. hexoses only B. pentoses only C. both hexoses and pentoses D. none of these View Answer Workspace Report Discuss in Forum Yeast is used in the production of A. ethyl alcohol B. acetic acid C. cheese D. curd View Answer Workspace Report Discuss in Forum S cerevisiae start producing ethanol with in A. 10 h B. 12 h C. 15 h D. 24 h..... As the fermentation for the ethanol production is over, the cells are separated to get the biomass of yeast cells that is used A. for next fermentation B. as single cell protein for animal feed C. as manure D. all of the above...

Multiple ovulation and embryo transfer (MOET) A. can increase the rate of progress in dairy cattle B. allows progeny testing of males C. allows progeny testing of females D. all of the above The technique, mainly used for the diagnosing birth defects in the fetus by means of needle, is called A. amniocentesis B. ectogensis C. transplantation D. all of the above... Which of these established cell lines originate from a mouse embryo? A. 3T3 B. BHK C. HeLa D. BTK ... Karyoplast is A. cells devoid of cell wall B. nuclei C. nuclei with only some residual plasma membrane D. cell with nucleus...

Which of the following best describes artificial insemination? A. Transplanting an embryo into the uterus B. Fertilization of an egg in a test tube C. Selectively breeding healthy animals D. Taking the sperm and placing it directly.... Which part of a cell carries the information that is passed from one generation to the next? A. Cell B. Nucleus C. Cytoplasm D. Chloroplast.... DNA is microinfected into the fertilized egg A. after the fusion of male and female nuclei B. before the fusion of male and female nuclei C. at the time of fusion of male and female nuclei D. any time, it can be infected In which year, Dolly the first mammalian clone was born? A. 1995 B. 1997 C. 1996 D. 1998....

Which of the following statement is correct? A. Variation is caused by genes B. Variation is caused by the environment C. Variation can be caused by both genes and the environment D. None of the above Which of the following gene have been introduced into the transgenic fish? A. Human or rat gene for growth hormone B. Chicken gene for delta crystalline protein C. E. coli gene for β-galactosidase D. All of the above.. Cloning is a method by which numbers of genetically identical organisms are derived from a single organism by A. vegetative propagation B. vegetative initiation C. vegetative termination D. none of these Which of the following is/are the method of transfection for making transgenic animals? A. Transfer of whole nuclei B. Transfer of whole individual chromosomes or fragment C. Transfer of DNA...

Superovulation is primarily the result of A. decreased atresia in medium and large follicles (>1.7 mm) B. increased atresia in medium and large follicles (>1.7 mm) C. increased atresia in the large follicles (<1.7 mm) D. decreased atresia in small follicles (<1.7 mm) Genetic change can occur only in A. one way B. two ways C. three ways D. four ways... Which of these carries the thousands of genes needed to allow animal and plant cells to pass on inherited characteristics? A. Chromosomes B. Chromatogram C. Chromatography D. Chromium Animal pharming can be defined as A. growing animals for farming B. programming animals to produce novel products C. generating transgenic animals for farming D. none of the above...

Which of the following is the technique used for the embryo culture? A. Organ cultures on plasma clots B. Organ cultures on agar C. Whole embryo cultures D. All of these... The major problem associated with the isolation of free cells and cell aggregates from organs is that of A. releasing the cells from their supporting matrix B. inhibiting the cells from their supporting matrix C. disintegrating the cells from their supporting matrix D. none of the above.... Some types of variation are due to changes in the genetic material. What is this type of change called? A. Fertilisation B. Mutation C. Radiation D. Sterilisation Which of the following is the process of choosing parent organisms for the characteristics that is wanted in their offspring? A. Active selection B. Reproductive selection C. Selective breeding D. Breeding selection....

Which of the following is not the explantation technique? A. Slide culture B. Carrel flask culture C. Roller test tube culture D. Adherent primary culture Cells which have undergone transformation frequently become A. anchorage independent B. anchorage dependent C. stable D. unstable Range of optimum glucose concentration present in the culture media is A. 5.5 - 55 mmol/litre B. 55 - 75 mmol/litre C. 75-105 mmol/litre D. 105-150 mmol/litre.... The technique of organ culture may be divided on the basis of employing A. solid medium B. liquid medium C. both (a) and (b) D. semi-solid medium At low glucose concentration, below 0.25 mmol/litre, large portions of glucose and glutamine is shunted via A. oxidative pathway B. anaerobic pathway...