Class 12th Biology 2016 Set1 Outside Delhi Board Paper Solution
(a) What do ‘Y and ‘B’ stand for in YAC’ and ‘BAC’ used in Human Genome Project (HGP). Mention their role in the project.
(b) Write the percentage of the total human genome that codes for proteins and the percentage of discovered genes whose functions are known as obs erved during HGP.
(c) Expand ‘SNPs’ identified by scientists in HGP.
(a) The BAC (Bacterial Artificial Chromosomes) and the YAC (Yeast Artificial Chromosomes) represent the host cells used for cloning of DNA fragments using specialised vectors.
(b) Less the 2% of the human genome codes for proteins. Less than 50% of the discovered genes have their functions known.
(c) SNP: Single Nucleotide Polymorphism. These are sites for single DNA base differences. SNPs hold promise for location of disease-associated sequences on chromosomes and tracing human history.
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Fill in the blanks:
(a) Humans reproduce __________. (asexually/sexually)
(b) Humans are__________. (oviparous/viviparous/ovoviviparous)
(c) Fertilization is __________ in humans. (external/internal)
(d) Male and female gametes are __________. (diploid/haploid)
(e) Zygote is __________. (diploid/haploid)
(f) The process of release of the ovum from a mature follicle is called__________.
(g) Ovulation is induced by a hormone called the __________.
(h) The fusion of male and female gametes is called _____________.
(i) Fertilisation takes place in _____________.
(j) Zygote divides to form _____________which is implanted in uterus.
(k) The structure which provides vascular connection between fetus and uterus is called ____________.