Theory of germplasm, Biology

Assignment Help:

THEORY OF GERMPLASM -

  • August Weismann (1834-1914) criticized the inheritance of acquired characters by putting forward the theory of continuity of germplasm.
  • According to this theory, the characters of influencing the germ cells are only inherited.
  • There is a continuity of germplasm (protoplasm of germ cells) is not transmitted to the next generation hence it does not carry characters to next generation.
  • Weismann disproved the inheritance of acquired characters by cutting off the tails of rats for about 20 generations and allowed them to breed but tailless rats were never born.
  • Weismann stated that organisms comprises of two types of protoplasm - the germplasm, the protoplasm present in germ cells only and which is passed on to the offsprings, and the somatoplasm, the protoplasm forming remain of the body part and plays no role in heredity.
  • Darlington commented - "Lamarck's theory is an evergreen superstition".

EXAMPLES AGAINST THE THEORY -

  • Muscles of arms and shoulder in blacksmiths.
  • Circumcison of foreskin of penis in jews and muslims.
  • Piercing of ear -lobe in Indian women.
  • Shaving of beard in man.
  • The wrestler's powerful muscles are not transmitted to the offsprings.
  • Chinese women used to wear iron shoes in order to have small feet, but their children at the time of birth always normal feet.

Related Discussions:- Theory of germplasm

Endomitosis, why and where endomitosis happen.........?

why and where endomitosis happen.........?

Respiratory system - developmental changes, Respiratory System - Developmen...

Respiratory System - Developmental Changes after Birth The new-born's lungs are collapsed and need powerful breaths to inflate them; airways too are small, offering remarkable

Determine the estimation of minerals in foods, Estimation of minerals in fo...

Estimation of minerals in foods The minerals in foods are determined by ashing or incineration at temperatures in the region of 500°C following standard procedure. This destroy

Research to improve health care delivery, Research to Improve Health Care D...

Research to Improve Health Care Delivery: Today, much  of health  care  delivery  system remains  imitative  and intuitive rather than innovative,  creative or  scientific in

Show classification of englearn dprantls system, Q. Show Classification of ...

Q. Show Classification of englearn dPrantls system? The outline and basis of classification of englearn d Prantl's system are given below: 1) Plant Kingdom has been divided,

Physiology of excretion, PHYSIOLOGY OF EXCRETION - 1 .      FORMATION...

PHYSIOLOGY OF EXCRETION - 1 .      FORMATION OF UREA - It takes place in liver. (i) Deamination (ii) Ornithine cycle or urea cycle - Explained by H.

What do you mean by amphibians of the plant world, Q. Why can the bryophyte...

Q. Why can the bryophytes be considered the "amphibians of the plant world"? Like adult amphibians, the bryophytes live in the terrestrial environment but they depend on water

Theory of natural selection, What key idea, contained in Malthus's essay on...

What key idea, contained in Malthus's essay on populations, helped Darwin formulate his theory of natural selection?

Immediate post-operative care to a cardiac patient, Immediate Post-operativ...

Immediate Post-operative Care The patient is accompanied to the ICU by a surgeon, anesthetist and the nurse who assisted for the surgery with portable ventilator and ECG

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd