1. 1 Organisms that are able to manufacture organic nutrients from substances in the abiotic environment are classified as (1) heterotrophs (3) predators (2) fungi (4) autotrophs   1   2   3   4   Hint Half-n-half Clue   2. 2 Which factor would have the greatest effect on the flow of energy into an ecosystem? (1) a large decrease in the amount of sunlight available (2) a large increase in the number of carnivores (3) a small increase in the number of decomposers (4) a small decrease in the amount of minerals available   1   2   3   4   Half-n-half Clue   3. 3 Which structures carry out life functions within cells? (1) tissues (3) organelles (2) organ systems (4) organs   1   2   3   4   Half-n-half Clue   4. 4 Which process is most directly responsible for maintaining internal stability in an organism when its environment is constantly changing? (1) digestion (3) reproduction (2) feedback (4) evolution   1   2   3   4   Half-n-half Clue   5. 5 The function of a cell depends primarily on its (1) life span (3) structure (2) color (4) movement   1   2   3   4   Half-n-half Clue   6. 6 In some cases, humans have chosen to mate certain individual farm animals within a species. For example, by allowing only the largest cattle to reproduce over many generations, strains of very large cattle have been produced. This process is known as (1) natural selection (2) direct harvesting (3) selective breeding (4) dynamic equilibrium   1   2   3   4   Half-n-half Clue   7. 7 A boy inherits genes for tallness, but his growth is limited as a result of poor nutrition. This is an example of (1) an inherited disorder (2) environmental influence on gene expression (3) expression of a hidden trait (4) a characteristic controlled by more than one pair of genes   1   2   3   4   Half-n-half Clue   8. 8 The sickle-cell trait is an inherited condition resulting from the presence of abnormal molecules of the protein hemoglobin in red blood cells. A person with the sickle-cell trait may have a child with the same condition because the child receives from the parent (1) abnormal red blood cells (2) abnormal hemoglobin molecules (3) a code for the production of abnormal hemoglobin (4) a code for the production of abnormal amino acids   1   2   3   4   Half-n-half Clue   9. 9 The sorting and recombining of genes during meiosis and fertilization usually leads to the production of (1) gametes with many copies of the same chromosome (2) embryos with traits identical to those of all other members of the species (3) zygotes with the genetic information to produce only females (4) offspring with some traits that did not appear in their parents   1   2   3   4   Half-n-half Clue   10. 10 Which situation would most likely produce a gene mutation in a squirrel? (1) The squirrel stops using its claws for digging. (2) The squirrel is exposed to radiation for several days. (3) Oak trees gradually become less common. (4) The weather becomes wetter for a short period of time.   1   2   3   4   Half-n-half Clue   11. 11 Which row in the chart below best describes what happens when some DNA bases are deleted from a gene?   1   2   3   4   Half-n-half Clue   12. 12 The diagram below represents a technique currently used by scientists in the field of biotechnology. Which statement describes a possible outcome of this technique? (1) The bacterium is able to produce a human hormone. (2) It allows the bacterium to grow in humans, since it contains a human gene. (3) It allows humans to become immune to an infection from this type of bacteria. (4) The bacterium can now produce human cells identical to cells of the DNA donor.   1   2   3   4   Half-n-half Clue   13. 13 When antibiotics were first developed, most infectious diseases could be controlled by them. Today, certain bacteria are resistant to many antibiotics. One possible explanation for this change is that (1) the antibiotics killed most of the bacteria that did not have a genetic variation for resistance (2) the bacteria needed to change in order to produce more antibiotics (3) some of the bacteria learned how to resist the antibiotics (4) antibiotics have become weaker over the years   1   2   3   4   Half-n-half Clue   14. 14 Thousands of genetically identical trees have been discovered growing in a remote, undisturbed mountain area in Colorado. These trees are most likely the result of (1) genetic engineering (2) asexual reproduction (3) meiotic cell division (4) biotechnology   1   2   3   4   Half-n-half Clue   15. 15 The ability of the human body to keep bloodsugar levels within a fairly narrow range, despite the intake of meals high in carbohydrates, is an example of (1) active transport (2) genetic recombination (3) homeostasis (4) digestion   1   2   3   4   Half-n-half Clue