Soil and air because it is needed for the development of living beings
Answer:
A scientific model is a representation model for a certain scientific concept. Scientific models make it easier to study a phenomenon as they tend to model out the exact phenomenons.
A drawing of an skeleton would be unclear as the children might not be able to locate certain features in the drawing. For example, a certain joint could be missed by the teacher in the drawing or the child might not exactly be able to locate where the joint or bone is present.
But as the model will be more real to the actual skeleton system hence, studying through a skeleton will make it a lot easier to study the human skeletal system.
The answer is A. <span>Solar energy is a renewable resource because it can't be used up, but oil is a nonrenewable resource because it will eventually run out.</span>
Answer:
When homologous chromosomes form pairs during prophase I of meiosis I, crossing-over can occur. Crossing-over is the exchange of genetic material between homologous chromosomes. ... It results in gametes that have unique combinations of chromosomes. In sexual reproduction, two gametes unite to produce an offspring.
Explanation:
Answer: Option B
Explanation:
In a typical energy pyramid the amount of energy that is being transferred is only 10% rest of the energy is lost in the form of heat.
The energy from the sun is converted in the form of chemical energy which is stored in the producers.
10 per cent of this energy is transferred to the next trophic level and rest of the energy is lost in the form of heat. This goes on, there is only a transfer of 10 % energy from the successive levels.
So, if the producers have 200 Kcal/m2/year energy the the primary consumers will have 10% of this energy which is equivalent to 20 Kcal/m2/year and then the secondary consumers will have 10 % of 20 Kcal/m2/year which is equivalent to 2 Kcal/m2/year.