nln pax questions and answers 100% correct

nln pax questions and answers 100% correct 1. Which of the following sentences is true? A. All organisms begin life as a single cell. B. Organisms begin life as multi-cellular. C. Some organisms begin life as a single cell and others as multi-cellular. D. None of the above. A: All organisms begin life as a single cell. 2. Scientists suggest that ________ has occurred through a process called ________. A. evolution/differentiation B. evolution/natural selection C. natural selection/homeostasis D. homeostasis/reproduction B: Scientists suggest that evolution has occurred through a process called natural selection. 3. What are the two types of measurement important in science? A. quantitative and numerical B. qualitative and descriptive C. numerical and scientific D. quantitative and qualitative D: The two types of measurement important in science are quantitative (when a numerical result is used) and qualitative (when descriptions or qualities are reported). 4. A normal human sperm must contain: A. an X chromosome. B. a Y chromosome. C. 23 chromosomes. D. B and C. E. A, B, and C. C: A normal sperm must contain one of each of the human chromosome pairs. There are 23 chromosome pairs in all. Of these, 22 are autosomal chromosomes, which do not play a role in determining gender. The remaining pair consists of either two X chromosomes in the case of a female or of an X and a Y chromosome in the case of a male. Therefore, a normal sperm cell will contain 22 autosomal chromosomes and either an X or a Y chromosome, but not both. 5. All living organisms on Earth utilize: A. oxygen. B. light. C. sexual reproduction. D. neurotransmitters. E. a triplet genetic code. E: All living organisms on Earth utilize the same triplet genetic code in which a three-nucleotide sequence called a codon provides information corresponding to a particular amino acid to be added to a protein. In contrast, many organisms, especially certain types of bacteria, do not use oxygen. These organisms live in oxygen-poor environments and may produce energy through fermentation. Other organisms may live in dark environments, such as in caves or deep underground. Many organisms reproduce asexually by budding or self-fertilization, and only the most evolutionarily advanced organisms make use of neurotransmitters in their nervous systems. 6. The major advantage of sexual reproduction over asexual forms is that: A. it requires two individuals. B. it promotes diversity. C. it produces more offspring. D. it can be undertaken at any time of year. E. it involves chromosomes. B: Sexual reproduction allows the genetic information from two parents to mix. Recombination events between the two parental copies of individual genes may occur, creating new genes. The production of new genes and of new gene combinations leads to an increase in diversity within the population, which is an advantage in terms of adapting to changes in the environment. 7. What is the second part of an organism's scie