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.
Answer:
Species separated by a physical barrier for a long time, suffer allopatric speciation, so they can not interbreed anymore.
Explanation:
Allopatric speciation consists of the geographic separation of a continuous genetic background giving place to two or more new geographically isolated populations. These separations might be due to migration, extinction of geographically intermediate populations, or geological events. In this speciation, some barriers impede genetic interchange, or genetic flow, as the two new populations that are separated can not get together and mate anymore. These barriers might be geographical or ecological.
Vicariance is the geographical separation of an original population into two or more new groups. Discontinuities in the physical environment like rivers, mountains, water, etc., are physical barriers that impede genetic flow between the separated groups.
The process of allopatric speciation involves different steps:
- The emergence of the barrier.
- Interruption in the genetic interchange
- The occurrence of new mutations and their accumulation in time in each population. Slow and gradual differentiation.
- Genetic divergence by natural selection and reproductive isolation makes it impossible for the two groups to mate even if the barrier disappears.
- Prezigotic isolation mechanisms favored by selection once occurs a secondary contact between the new species in formation.
The answer is A The pancreas regulates blood glucose through hormones.
Answer:
Cellular Respiration: a process able to extract a large amount of energy from food molecules. In eukaryotic cells oxygen is a required component. This metabolic process is the main reason that animals have elaborate gas exchange organs such as lungs, gills and other systems. The goal of these systems is, of course, to get access to oxygen and to get rid of carbon dioxide.
Explanation: