There are five mechanisms involve in diversity of organisms:
genetic drift, mutation, natural selection, gene flow and non random mating.
Explanation:
Genetic drift: It is a mechanism in which frequency of the allele changes within a population due to random sampling. It causes decrease in diversity in organism and can result in new species.
Mutation: Mutation in the genes is the most important reason of diversity.the change in DNA causes introduction of new alleles. Harmful mutations do not le species evolve by delimiting them from reaching sexual maturity.
Gene flow: The allele flow happens when a new gene is introduced into a population either by immigration or random mating. when two populations of same species share genes, variation occurs.
Natural selection: The favourable traits for survival are transferred to the offspring. It allows them to adapt better to the environment. It allows maintenance diversity of organism.
Non random mating: The mating between the individual with varied genotype will result in genetic variation.
1. The answer is; B
This is because the soup has a higher temperature than the surrounding air. The heat will move from hotter object to the cooler object in search of thermal equilibrium. Heat transfer will only stop when the soup and the surrounding air have more or less the same temperatures.
2. The answer is; B
No mas is required because radiation (which are mainly electromagnetic waves) can transfer energy even through a vacuum. Other forms of energy transfer (such as convection and conduction)involve the transfer of vibrational motion from one molecule of matter to the next.
3. The answer is; D
The sun rays (which are electromagnetic waves that travel in photons) travel from the sun and through the vacuum of space before they reach the earth. When the photons hit the molecules that make up your skin, they energize them and cause them to vibrate more energetically. As they, differentially, lose this kinetic energy (when resuming a lower excitation state), this energy is expended as heat which you feel on your face.
4. The answer is; D
To start with, it is important to note that water is not a good conductor of heat. Therefore, as it is heated from below by the Bunsen burner, the water at the bottom of the glass gets warmer that than at the top of the glass. Warm water is less dense than cool water hence begin to rise while the cooler water from the top replaces the rising warm water. This process continues and forms convection currents until the water starts to boil.
5. The answer is; B
When the can is opened, it exposes the soup to the environment. This way the heat from the soup (due to thermal disequilibrium) transfers from the soup to the air. Because the soup is hotter, it loses heat energy to the surrounding as dictated by laws of thermodynamics.
Question 3: The solution is considered to be hypotonic with respect to the cytoplasm.
Question 4: The channel proteins are called aquaporins.
Question 5: The molecule is cholesterol.
The understanding of evolutionary processes has helped scientists in the field of artificial selection. The best example of artificial selection is the production of pesticide-resistant potatoes.
Answer:
Cells are the basic units of life, and can exist by themselves or as part of a larger organism. Viruses, on the other hand, are non-living infectious particles. They are much smaller than a cell and need a living host to reproduce. Cells and viruses have nucleic acid genomes based on the same genetic code that’s used in the cells. Cells and viruses also have genetic variation and can evolve.