Class 12 Biology - Chapter Evolution NCERT Solutions | How do we compute the age of a fossil?
Welcome to the NCERT Solutions for Class 12th Biology - Chapter Evolution. This page offers a step-by-step solution to the specific question from Excercise 0 , Question 6: how do we compute the age of a fossil....
Question 6
How do we compute the age of a fossil?
Answer
There are various methods for the determination of age of fossils and these are following:
- Relative dating method: relative dating of the rocks was carried out by estimating the position and the rate of erosion in particular environment. Older rocks, being deeper had older or ancient fossils; and superficial rocks had more recent fossils. It does not tell any specific dates, only estimates whether the object is younger or older that are found at the site.
- Absolute dating method: this method determines how much time have passed since the rock formation occurred by measuring the radioactive decay; or based on the property of spontaneous decay of unstable radioactive nuclei into stable form at the constant rate. This involves three techniques: Uranium- Lead Technique, Carbon (C14) Dating Technique and Potassium- Argon Technique.
More Questions From Class 12 Biology - Chapter Evolution
- Q:- Describe one example of adaptive radiation.
- Q:- Explain antibiotic resistance observed in bacteria in light of Darwinian selection theory.
- Q:- Can we call human evolution as adaptive radiation?
- Q:- Try to trace the various components of human evolution (hint: brain size and function, skeletal structure, dietary preference, etc.)
- Q:-
Practise drawing various animals and plants.
- Q:- Using various resources such as your school library or the internet and discussions with your teacher, trace the evolutionary stages of any one animal say horse.
- Q:- List 10 modern-day animals and using the internet resources link it to a corresponding ancient fossil. Name both.
- Q:- Attempt giving a clear definition of the term species
- Q:- Find out from newspapers and popular science articles any new fossil discoveries or controversies about evolution.
- Q:- Find out through internet and popular science articles whether animals other than man have self-consciousness.
Popular Questions of Class 12 Biology
- Q:- Why is reproduction essential for organisms? Answer
- Q:- Name the parts of an angiosperm flower in which development of male and female gametophyte take place.
- Q:-
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 ____________. - Q:- What do you think is the significance of reproductive health in a society?
- Q:- Mention the advantages of selecting pea plant for experiment by Mendel.
- Q:- Group the following as nitrogenous bases and nucleosides:
Adenine, Cytidine, Thymine, Guanosine, Uracil and Cytosine. - Q:- What are the various public health measures, which you would suggest as safeguard against infectious diseases?
- Q:- Explain in brief the role of animal husbandry in human welfare.
- Q:- Bacteria cannot be seen with the naked eyes, but these can be seen with the help of a microscope. If you have to carry a sample from your home to your biology laboratory to demonstrate the presence of microbes under a microscope, which sample would you carry and why?
- Q:- Can you list 10 recombinant proteins which are used in medical practice? Find out where they are used as therapeutics (use the internet).
Recently Viewed Questions of Class 12 Biology
- Q:- List all the wastes that you generate, at home, school or during your Trips to other places, could you very easily reduce? Which would be Difficult or rather impossible to reduce?
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