Question: Answer the following question given this paragraph: Bases are less common as foods, but they are nonetheless present in many household products. Many cleaners contain ammonia, a base. Sodium hydroxide is found in drain cleaner. Antacids , which combat excess stomach acid, are comprised of bases such as magnesium hydroxide or sodium hydrogen carbonate. Q: What are antacids comprised of? Choices: - gases - solids - acids - bases A:
Answer: bases

Question: Answer the following question given this paragraph: 22.11.5 Pyrrophytes Pyrrophytes are unicellular, photosynthetic, and mostly aquatic. They have protective coats composed of stiff cellulose. They are more easily identifiable, due to the presence of two flagellae. The longer flagellae propels the dinoflagellate, while the second shorter, flatter flagellae functions as a rudder. Some species of pyrrophytes are zooxanthellae. Since they lack cellulose plates, they make their home in coral reefs and animals, such as sea anemones, and molluscs. In returning the favour of sheltering them, dinoflagellates provide carbohydrates to their host through photosynthesis. This is why there are nutrient-rich coral reefs in malnutritions water. A negative aspect of pyrrophytes is that under certain conditions, species of dinoflagellates reproduce rapidly to form a harmful algal bloom (HAB), known as a red tide if dinoflagellates are the cause. Such pyrrophytes can produce toxins which may injure or kill wildlife, and additionally any consumers of contaminated wildlife. Q: What function does the longer flagellae perform in dinoflagellates? Choices: - defends - grasps - attacks - propels A:
Answer: propels

Question: Answer the following question given this paragraph: If the two isolated populations are brought back together and the hybrid offspring that formed from matings between individuals of the two populations have lower survivorship or reduced fertility, then selection will favor individuals that are able to discriminate between potential mates of their own population and the other population. This selection will enhance the reproductive isolation. Isolation of populations leading to allopatric speciation can occur in a variety of ways: from a river forming a new branch, erosion forming a new valley, or a group of organisms traveling to a new location without the ability to return, such as seeds floating over the ocean to an island. The nature of the geographic separation necessary to isolate populations depends entirely on the biology of the organism and its potential for dispersal. If two flying insect populations took up residence in separate nearby valleys, chances are that individuals from each population would fly back and forth, continuing gene flow. However, if two rodent populations became divided by the formation of a new lake, continued gene flow would be unlikely; therefore, speciation would be more likely. Biologists group allopatric processes into two categories. If a few members of a species move to a new geographical area, this is called dispersal. If a natural situation arises to physically divide organisms, this is called vicariance. Scientists have documented numerous cases of allopatric speciation taking place. For example, along the west coast of the United States, two separate subspecies of spotted owls exist. The northern spotted owl has genetic and phenotypic differences from its close relative, the Mexican spotted owl, which lives in the south (Figure 11.15). The cause of their initial separation is not clear, but it may have been caused by the glaciers of the ice age dividing an initial population into [5] two. Q: What is the term for a natural situation which arises to physically divide organisms? Choices: - assimilation - reproduction - extinction - vicariance A:
Answer:
vicariance