Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
From Molecules to the First Cell
The prebiotic conditions on the earth in all probability were volcanic eruptions, lightning and heavy rains. There was no trace of free oxygen or an ozone layer in the atmosphere to absorb ultraviolet radiations from the sun. It is assumed that organic molecules would have originated in such climatic conditions. This is described as their abiotic origin. Laboratory experiments from 1953 onwards prove that organic molecules like amino acids, proteins, nucleotides, nucleic acids, lipids and ATP can be formed in similar conditions on the earth. Stan1r.y Miller's experiment described below is one such experiment (Fig. shown below). It is possible that such organic molecules similar to those synthesised in Miller's experiment would have got accumulated at several places in high concentration, giving rise to a kind of liquid soup.
Scientists have three different speculatiohs about the composition of a protobiont. Some consider it'as an aggregate of electrically charged molecules with water around them acting as a boundary and this is called as coacervate model (Fig. shown below). This model was proposed by Alexander Oparin. Sidney Fox proposed another model for protobiont formation called protenoid microsphere model. According to this model when water free mixtures of amino acids are heated at high temperature, they pol.yinerise to form protein-like molecules, called proteinoids. These can persist only if cooled quickly. According to a third model called as the lipid bilayer model of Richard Goldacre, an abiotically synthesised phospholipid bilayer was formed around a central space containing organic molecules. All such models are without any experimental or theoretical evidence. However, the supporters of each model try to explain how some life-processes like osmosis and budding, can be camed out by such protobionts.
Regulation of Glycogen Metabolism It is important for you to understand that glycogenesis and gluconeogenesis are regulated reciprocally. There is a hormonal regul
Counseling is a process whereby a qualified person purposefully assists another person to handle his or her problems. Counselling is not just giving advice. It is dependent on mut
Structure and development of leaf
why the study of microflora
What do you understand by Polyp? The sessile, asexual stage in the cnidarian life cycle. In some species they are independent organisms; in others, they form colonies where som
Explain the Impedance method to Measure Body Fats? Impedance method: This method can give entire body composition like total body water (TBW), fat free mass (FFM) or lean body
Q. What is haemoglobin? What is the inorganic element that is basic of the composition of haemoglobin? Haemoglobin is the protein present in the blood responsible for the trans
Yellow fever Yellow fever also known as Black Vomit and American plaque is a viral disease primarily of monkeys and transmitted to man by female Aedes mosquitoes. It is caused
Explain about the Demand curve or schedule in short. The demand curve or demand schedule shows the total quantity purchased through all buyers, within aggregate, into the marke
The use and transfer of energy in all cells involves same compound, ATP. The letters ATP stand for chemical: a) Adenosine triphosphate b) Aluminum trioxide c) Atrophine t
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd