Question
Enumerate the salient features of human genome.

Answer

Salient features of Human Genome:
  1. The human genome contains 3164.7 million nucleotides (base pairs).
  2. The size of the genes varies; an average gene consits of 3000 bases, while the largest gene, dystrophin consists of 2.4 million bases.
  3. The total number of genes is estimated to be 30000 and 99.9% of the nucleotides are the same in all humans.
  4. The functions of over 50% of the discovered genes are not known
  5. Only less than 2% of the genome codes for proteins.
  6. Repetitive segments make up a large portion of the human genome.
  7. Repetitive sequences throw light on chromosome structure and dynamics and evolution, though they are thought to have no direct coding functions.
  8. Chromosome 1 has 2968 genes and Y-chromosome has the least number (231 genes).
  9. Scientists have identified about 1.4 million locations, where DNA differs in single base in human beings; these are called single nucleotide polymorphisms (SNPs).

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Describe biological evolution from paleontological and embryological evidences.
Describe in detail the various levels of biodiversity.
What is meant by immunity? What are the four barriers to innate immunity? Explain . Draw a labelled diagram of the structure of an antibody molecule.
In a biology class, teacher was telling the students that the structures/components and their functions in a watch can be compared with various levels of organisation we find in nature. Radhika was surprised and asked teacher to explain it. Teacher got impressed with Radhika's interest and explained that there is a systematic arrangement of smaller and simpler components into larger one in a hierarchy or pyramid having different levels where each level is formed of components of lower level and itself becomes part of higher level for achieving a common goal.
(i) What are the four levels of biological organisation found in nature?
(ii) What is the basic unit of ecological organisation?
(iii) Define community.
(iv) What values are shown by Radhika?
Discuss the role of healthy ecosystem services as a pre-requisite for a wide range of economic, environmental and aesthetic goods and services.
  1. Draw a diagram of a mature embryo sac of an angiosperm and label the following parts in it:
  1. Filiform apparatus.
  2. Synergids.
  3. Central cell.
  4. Egg cell.
  5. Polar nuclei.
  6. Antipodals.
  1. Write the fate of egg cell and polar nuclei after fertilisation.
Complete the given table.
Name of the organism Product/ Enzyme/ Bioactive male cule
Aspergillus niger (i)
(ii) Ethanol
(iii) Cyclosporin-A
(iv) Acetic acid
Monascus purpureus (v)
Streptococcus (vi)
Draw a labelled diagram of the sectional view of a mature pollen grain in angiosperms. Explain the functions of its different parts.
Give an account of the methods used in sequencing the human genome.
What do you understand by the evidences of Evolutions describe in detail with suitable example the three evidences of evolution?