Answer the following question given this paragraph: How does sap get to the tops of tall trees? (Recall that a column of water can only rise to a height of 10 m when there is a vacuum at the topsee Example 11.5. ) The question has not been completely resolved, but it appears that it is pulled up like a chain held together by cohesive forces. As each molecule of sap enters a leaf and evaporates (a process called transpiration), the entire chain is pulled up a notch. So a negative pressure created by water evaporation must be present to pull the sap up through the xylem vessels. In most situations, fluids can push but can exert only negligible pull, because the cohesive forces seem to be too small to hold the molecules tightly together. But in this case, the cohesive force of water molecules provides a very strong pull. Figure 11.36 shows one device for studying negative pressure. Some experiments have demonstrated that negative pressures sufficient to pull sap to the tops of the tallest trees can be achieved. Q: How does sap get to the tops of tall trees? Choices: - through suction power - via Coriolis forces - through pressure from below - through negative pressure A:
through negative pressure
Answer the following question given this paragraph: Innate behaviors occur in all animals. However, they are less common in species with higher levels of intelligence. Humans are the most intelligent species, and they have very few innate behaviors. The only innate behaviors in humans are reflexes. A reflex is a response that always occurs when a certain stimulus is present. For example, a human infant will grasp an object, such as a finger, that is placed in its palm. The infant has no control over this reaction because it is innate. Other than reflexes such as this, human behaviors are learnedor at least influenced by experiencerather than being innate. Q: Innate behaviors occur in all animals. however, they are less common in species with higher levels of what? Choices: - hormones - interdependence - nonverbal communication - intelligence A:
intelligence
Q: Answer the following question given this paragraph: The experiment is a cornerstone in the scientific approach to gaining deeper knowledge about the natural world. Scientists use the principles of their hypothesis to make predictions, and then test them to see if their predictions are to be confirmed or rejected. Q: Scientists use the principles of what to make predictions, which they then test? Choices: - their teachers - their guesses - their faith - their hypothesis A:
A: their hypothesis
Question: Answer the following question given this paragraph: Both stages of photosynthesis take place in chloroplasts. The light reactions take place in the thylakoid membranes, and the Calvin cycle takes place in the stroma. Q: The light reactions take place in which membranes? Choices: - the cell membranes - the phospholipid - the stroma - the thylakoid A:
Answer: the thylakoid
*Question*
Answer the following question given this paragraph: Hemoglobin is a compound in the class of compounds called proteins. Proteins are one of four classes of biochemical compounds, which are compounds in living things. (The other three classes are carbohydrates, lipids, and nucleic acids. ) Proteins contain carbon, hydrogen, oxygen, nitrogen, and sulfur. Protein molecules consist of one or more chains of small molecules called amino acids. Q: How many classes of biochemical compounds are there? Choices: - one - five - three - four A:
**Answer**
four
Answer the following question given this paragraph: Q: What are the most numerous blood cells? Choices: - neutrophils - white blood cells - platelets - red blood cells A:
red blood cells