Answer the following question given this paragraph: Figure 20.33 The outer surface of the heart changes from positive to negative during depolarization. This wave of depolarization is spreading from the top of the heart and is represented by a vector pointing in the direction of the wave. This vector is a voltage (potential difference) vector. Three electrodes, labeled RA, LA, and LL, are placed on the patient. Each pair (called leads I, II, and III) measures a component of the depolarization vector and is graphed in an ECG. Q: The outer surface of the heart changes from positive to negative during what? Choices: - inflammation - permeability - reproduction - depolarization A:
depolarization
(Question)
Answer the following question given this paragraph: Your heart pumps blood around your body. But how does your heart get blood to and from every cell in your body? Your heart is connected to blood vessels such as veins and arteries. Organs that work together form an organ system . Together, your heart, blood, and blood vessels form your cardiovascular system . Q: What organ system is comprised of your heart, blood, and blood vessels all working together? Choices: - thoraxic system - nervous system - digestive system - cardiovascular system A:
(Answer)
cardiovascular system
Ques: Answer the following question given this paragraph: Ring species Ring species demonstrate a version of allopatric speciation. Imagine populations of the species A. Over the geographic range of A there exist a number of subpopulations. These subpopulations (A1 to A5) and (Aa to Ae) have limited regions of overlap with one another but where they overlap they interbreed successfully. But populations A5 and Ae no longer interbreed successfully are these populations separate species? In this case, there is no clear-cut answer, but it is likely that in the link between the various populations will be broken and one or more species may form in the future. Consider the black bear Ursus americanus. Originally distributed across all of North America, its distribution is now much more fragmented. Isolated populations are free to adapt to their own particular environments and migration between populations is limited. Clearly the environment in Florida is different from that in Mexico, Alaska, or Newfoundland. Different environments will favor different adaptations. If, over time, these populations were to come back into contact with one another, they might or might not be able to interbreed successfully - reproductive isolation may occur and one species may become many. Q: Organisms categorized by what species descriptor demonstrate a version of allopatric speciation and have limited regions of overlap with one another, but where they overlap they interbreed successfully?. Choices: - surface species - fitting species - species complex - ring species A:
Ans: ring species
(Q).
Answer the following question given this paragraph: Q: What unit of measurement is typically used for rainfall? Choices: - gallons - feet - pounds - inches A:
(A).
inches
Ques:Answer the following question given this paragraph: Farsightedness is also known as hyperopia . It affects about one fourth of people. People with hyperopia can see distant objects clearly, but nearby objects appear blurry. In hyperopia, the eye is too short. This results in images being focused in back of the retina ( Figure above ). Hyperopia is corrected with a convex lens, which curves outward like the outside of a bowl. The lens changes the focus so that images fall on the retina as they should. Q: What do doctors call farsightedness or the inability to see close objects clearly? Choices: - hypopia - dysarthria - myopia - hyperopia A:

Ans:hyperopia
Answer the following question given this paragraph: Photography by Kat. Ferns are common in the understory of the tropical rainforest . CC BY 2.0. Q: In a tropical rainforest, where are ferns common? Choices: - forrest floor - emergent - canopy - understory A:
understory