Answer:
The correct answer would be the virus envelope.
Viral envelope is a protective covering present around the capsid proteins in some viruses.
It is usually derived from the cell membrane of the host and thus it is composed of lipid and viral proteins.
It provides stability to the viral particle, helps in protecting the viral genome, and aids in the fusion of the virus with the membrane of the host.
Examples of viruses in which envelope is present: herpesviruses, poxviruses, flavivirus, hepatitis D et cetera.
Examples of viruses in which envelope is absent: adenoviridae
, papillomaviridae
, picornaviridae
, caliciviridae et cetera.
Answer:
According to the law of conservation of matter, matter is never created or destroyed but it can change from one form to another. Most of the biomass in a food web gets converted at each trophic level and it no longer remains apart of the food web. Most of the biomass is released into the atmosphere in the form of heat and hence cannot be transferred to the other trophic level. Also, matter is used up by the organism itself and converted into different forms. Most of the matter might get accumulated in the soil when the organisms of a trophic level die.
<u>Answer</u>:
The mass of a star can be determined by studying binary star systems.
<u>Explanation</u>:
In this system it consists of two stars, revolving round the same bary-centre. The systems having two or may say more than two are called as the multiple star system. This zone is also a habitable zone, here the water exists in the liquid form. We could have sometime seen the two stars together. They are also very capable of strengthening the terrestrial planets inside the stable orbital ranges. They have generally two orbits like P-type as well as circumbinary.
Question:
<em>The diagram shows the potential energy changes for a reaction pathway.</em>
Part 1: Does the diagram illustrate an endothermic or an exothermic reaction? Give reasons in support of your answer.
Part 2: Describe how you can determine the total change in enthalpy and activation energy from the diagram and if each is positive or negative.
Answer:
Part 1: The diagram illustrates an endothermic reaction as the products has a higher potential energy than the reactants do. There is a positive slope of the diagram and there is enough energy to meet the activation energy requirement.
Part 2: You can determine the total change in enthalpy and activation energy from the diagram by the potential energy of the reactants. If the reactants have a high potential energy, then the enthalpy is also high, and if the reactants have a low potential energy, then the enthalpy is low. You can determine if the diagram is positive or negative by knowing if its an endothermic or exothermic reaction. An endothermic reaction is positive because the products are higher than the reactants and a exothermic reaction is negative because the reactants are higher than the products.
