Answer:
Factors that remain constant from experiment to experiment are the constants.
Explanation:
A constant in an experiment is also known as a <em>control variable</em>. It is the part of an experiment that must stay the same in order to validate the experiment. If the constant were to change, the results would be skewed and therefore false.
i.e. you want to test the rate of growth of lima bean plants in different types of lighting. You believe that a lima bean plant that grows in yellow will grow faster and stronger than a lima bean plant that grows in blue or red light.
In this experiment, the constant would be the lima bean plant. You cannot change the type of seed or else your experiment is invalidated. If you tried to use a sunflower seed in the blue lighting and a tomato seed in the red lighting, your results would be invalidated and skewed.
Answer: this is called passive transport and it does not require energy.
Answer:
The correct answer is b. must be present in a population before natural selection can act upon the population
Explanation:
Genetic variation can be caused by mutation, recombination between chromosomes during meiosis and by fusion of two genetically different gametes during sexual reproduction.
This genetic variation is necessary for the evolution of any population. Natural selection acts on every individual and it decreases the frequency of those alleles that are not suited for the environment and increase the frequency of those alleles which helps the individual to survive in the changing environment.
Therefore genetic variation must be present in the population before natural selection act on the.
Answer:
Explanation:
Pyramid is the use of graph to represents the flow of energy in each trophic level. There are five trophic level and each has its own energy level pyramid help to show the energy at each level.
Each energy level must have at least One tenth of the energy level of the organisms before itself, this indicates that the energy in the lower tropic level is higher than the trophic level above.
Hence, carnivores cannot be more than herbivores in a biomass they need enough of herbivores to survive in the biomass as the energy level moves from the herbivores to the carnivores.