The correct options are as follows:
1. D.
Natural selection refers to the process by which living organisms that are more adapted to their environments usually survive and produce offspring that are like them. In the case of giraffes, the giraffes with the longest necks were able to survive in their environment and they reproduce offspring that are like them.
2. D
In the scientific world, scientists have open minds and they welcome all new ideas. These new ideas have to be tested to ensure that they are correct and superior to the facts that are already known. When a new hypothesis is put forward by a scientist, many scientists all over the world will test the hypothesis is order t confirm if it correct. If the hypothesis is found to be correct it will be accepted by all scientists.
3. A.
DNA test is a laboratory analysis that can be used to assess the level of relationship between living organisms. Related living organisms usually have some similar genes in their DNA, the level of closeness of these organisms will determine the quantity of similar genes that will be found in their DNA. Unrelated organisms on the other hand will have little or no similar genes in their DNA.
4. C.
The genetic code is the same across species, this fact points to the possibility that all living organisms originated from common ancestors. This support the evolution theory which stated that all living organisms descended from a common ancestor.
5. B.
Antibiotic drugs are usually effective against bacteria and other microbes, but the microbes can evolve and develop resistance to these drugs. Microbes are considered to have evolved when drugs that are used to inactivate them before no longer have any effect on them, thus they can easily survive in the presence of the drugs.
6. B.
If a particular specie of animal is able to avoid predators, it will increase in number more that those that are prey on by predators. The kings snakes were probably able to avoid predators, that is why, they were able to survive, reproduce offspring and increase in population in that particular ecosystem.
Answer:
A. Transport of materials in xylem
Xylem tissue helps in the transport of water and minerals
Water is transported upwards from roots to aerial parts of plants
Transport in xylem requires physical forces such as transpiration pull.
B. Transport of materials in phloem
Phloem tissue helps in the transport of food.
Transport of food in phloem requires energy in the form of ATP.
Food is transported in both upward and downward directions.
Answer:
The process of respiration can take place in the presence as well as absence of oxygen. Hence, respiration is of two types: 1. Aerobic respiration and. 2. Anaerobic respiration.
Aerobic respiration is far more energy-efficient than anaerobic respiration.
Aerobic processes produce up to 38 ATP per glucose.
Anaerobic processes yield only 2 ATP per glucose.
Explanation:
Answer: correct: The CAP-cAMP complex unbends the DNA loop, thereby allowing binding of RNA polymerase
Explanation:
The CAP-cAMP complex unfolds the DNA loop, allowing the binding of RNA polymerase. The catabolite activating protein, when bound with cAMP, is known to stimulate the transcription of the operon lactose genes, being necessary for the reaction RNA polymerase
