Answer:
Option C
Explanation:
Dr. Leland Hartwell used baker’s yeast, <em>Saccharomyces cerevisiae</em>, as a model system, which was a highly suitable model for cell cycle studies. He introduced the concept of Checkpoints where he said cells are arrested if damaged so that the cells repair system can work to correct such damages. Dr. Paul Nurse used a different type of yeast, <em>Schizosaccharomyces pombe</em>, a type of yeast distantly related to the baker's yeast as a model organism.
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.
Answer:Sea levels change for three main reasons: 1) As water warms and cools it expands and contracts; 2) The amount of water contained as ice on land surfaces changes over time; 3) The Earth's surface is dynamic and can move vertically.
Explanation:The first two reasons are directly caused by global temperature changes.
Glycolysis starts with one molecule of glucose<span> and ends with two </span>pyruvate<span> (pyruvic acid) molecules, a total of four </span>ATP<span> molecules, and two molecules of </span>NADH<span> .
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