Answer: This is how I completed mine. Try taking some ideas from this.
Explanation:
B they are <span>used for the process of gene transfer</span>
Answer: D) much slower
Explanation:
The circulatory system, made up of arteries and veins, is fundamental to maintaining life. Its function is the delivery of oxygen and nutrients to all cells, as well as the removal of carbon dioxide and waste products, the maintenance of physiological pH, and the mobility of the elements, proteins, and cells of the immune system. An artery is each of the vessels that carry blood with oxygen from the heart to the capillaries of the body. They arise from a ventricle and their walls are very strong and elastic to resist the pressure that the blood exerts when it is pumped out of the heart.
Capillaries are very small diameter, thin-walled blood vessels connect small arteries (arterioles) to veins, allowing nutrients and oxygen to pass through to tissues. The main function of the capillaries is the exchange of substances between the light of the capillaries and the cell interstice of the tissues.
When the blood reaches the capillary bed, the speed with which it circulates inside these vessels is very low. This is due to the fact that in a branching system of tubes, the speed decreases proportionally to the increase in the joint section of the branches. Thus, in the aorta, which has a small section, the speed is very high (400 mm/sec), it decreases at the level of the arteries and arterioles and at the capillary level it becomes minimal (0.1 mm/sec). <u>This fact, together with the thinness of the capillary wall, provides the necessary conditions of time and space for the exchange to take place in the most optimal way.</u>
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Some mutations don't have any noticeable effect on the phenotype of an organism. This can happen in many situations: perhaps the mutation occurs in a stretch of DNA with no function, or perhaps the mutation occurs in a protein-coding region, but ends up not affecting the amino acid sequence of the protein.
Answer no 8:
The correct option is D) Antelopes with muscular legs are bale to outrun their predators better than antelopes with poor muscle tone. Thus they lived to reproduce.
Explanation:
Genetic variations in a population are the main reason that natural selection tends to occur. Natural selection favours those organisms which have better characteristics.The organisms with better traits are able to reproduce and pass on their characteristics to their offsprings.
Answer No 10:
The correct option is A) Phenotype directly influences the interaction of an organism with its environment.
Explanation:
The interactions between the phenotypic traits and the environment analyze whether a particular organism will be able to survive and pass on its characteristics to its offspring. Hence, the phenotype directly influences the interaction of an organism with its environment.
Answer No 9
The correct option is A) resistance to a virus
Explanation:
Mutations can be described as any changes which occur in the DNA of an organism. Mutations might be beneficial or harmful depending on the location where the mutation arises. Viruses are usually harmful for eukaryotes. Hence, the correct option is A.
Answer No 11:
The correct option is C) Giraffes with longer necks survived because they were better suited to the environment.
Explanation:
Natural selection tends to favour those organsims which are better suited to live in an environment. Those organisms with better characteristics are able to survive and pass on their traits to their offsprings.
The giraffes with longer necks were better adapted to live in the environment and hence were favoured by natural selection.
Answer No 12:
The correct option is D) selective breeding
Explanation:
Selective breeding can be described as a technique in which organisms with better characteristics are crossed, so that offsprings with better characteristics can be produced. Selective breeding is done by humans where as natural selection is done by the nature.