Answer:
1.Observation and description of a phenomenon. The observations are made visually or with the aid of scientific equipment.
2.Formulation of a hypothesis to explain the phenomenon in the form of a causal mechanism or a mathematical relation.
3.Test the hypothesis by analyzing the results of observations or by predicting and observing the existence of new phenomena that follow from the hypothesis. If experiments do not confirm the hypothesis, the hypothesis must be rejected or modified (Go back to Step 2).
4.Establish a theory based on repeated verification of the results.
Explanation:
Answer:
A
Explanation:
Acids and bases when mixed neutralize eachother. and 7 is neutral on the PH scale
Answer:
Yes both are different. In directional selection one of the extreme traits is favored, whereas in disruptive selection both the extreme traits are favored.
Explanation:
Directional: If selection acts to eliminate one extreme form and supports the other extreme then the peak shifts in the direction which is selected by the nature.
Disruptive: If the selection does not favor the mean character value, rather favors both the peripheral character values then this kind of selection is called disruptive selection.
Answer:
d.The wing-assisted incline running theory postulates that wings were initially used to maintain balance while climbing up slopes.
Explanation:
Two theories were given to explain the origin of avian flight. The top-down theory suggested that the birds' ancestors were tree dwelling species. They took help of wings to glide from tree to tree in order to avoid predator or catch prey. The bottom up theory suggested that the birds' ancestors were ground dwelling species. They took help of wings to maintain a balance and provide a lift for efficient running.
Wing-assisted incline running was a mixture of both the above theories and gave a balanced view point. According to it, birds' ancestors used wings to maintain a balance while running up inclined slopes. The wings helped them to save energy while scaling slopes and eventually a flight mechanism was also developed.
Answer:
sister chromatids separate and begin to move towards the pole of the cell during anaphase.