Answer the following question given this paragraph: In plants, most chloroplasts are found in the leaves. Therefore, all the raw materials needed for photosynthesis must be present in the leaves. These materials include light, water, and carbon dioxide. The shape of the leaves gives them a lot of surface area to absorb light for photosynthesis. Roots take up water from the soil. Stems carry the water from the roots to the leaves. Carbon dioxide enters the leaves through tiny openings called stomata. (The oxygen released during photosynthesis also exits the leaves through the stomata. ). Q: Where are most chloroplasts found in plants? Choices: - roots - stems - flowers - leaves A:
leaves
Answer the following question given this paragraph: Each myofibril is made up of two types of proteins, called actin and myosin. These proteins form thread-like filaments. Q: Each myofibril is made up of two types of proteins, called actin and what? Choices: - dynein - elongation - Fatty Acid - myosin A:
myosin
Q: Answer the following question given this paragraph: Density is an important physical property of matter. It reflects how closely packed the particles of matter are. Density is calculated from the amount of mass in a given volume of matter, using the formula:. Q: What physical property of matter reflects how closely packed the particles are? Choices: - volume - strength - diameter - density A:
A: density
Question: Answer the following question given this paragraph: Stems hold plants upright, bear leaves and other structures, and transport fluids between roots and leaves. Like roots, stems contain dermal, ground, and vascular tissues. Trees have woody stems covered with bark. Q: What part of the plant holds the plant upright? Choices: - roots - leaves - notochord - the stem A:
Answer: the stem
*Question*
Answer the following question given this paragraph: Convection within the Earth's mantle causes the plates to move. Mantle material is heated above the core. The hot mantle rises up towards the surface ( Figure below ). As the mantle rises it cools. At the surface the material moves horizontally away from a mid-ocean ridge crest. The material continues to cool. It sinks back down into the mantle at a deep sea trench. The material sinks back down to the core. It moves horizontally again, completing a convection cell. Q: What does convection within the earth's mantel cause? Choices: - volcanos - hurricanes - microorganisms to move - plates to move A:
**Answer**
plates to move
Answer the following question given this paragraph: Role of Feedback Loops The contribution of feedback loops to homeostasis will only be briefly reviewed here. Positive feedback loops are characterized by the release of additional hormone in response to an original hormone release. The release of oxytocin during childbirth is a positive feedback loop. The initial release of oxytocin begins to signal the uterine muscles to contract, which pushes the fetus toward the cervix, causing it to stretch. This, in turn, signals the pituitary gland to release more oxytocin, causing labor contractions to intensify. The release of oxytocin decreases after the birth of the child. The more common method of hormone regulation is the negative feedback loop. Negative feedback is characterized by the inhibition of further secretion of a hormone in response to adequate levels of that hormone. This allows blood levels of the hormone to be regulated within a narrow range. An example of a negative feedback loop is the release of glucocorticoid hormones from the adrenal glands, as directed by the hypothalamus and pituitary gland. As glucocorticoid concentrations in the blood rise, the hypothalamus and pituitary gland reduce their signaling to the adrenal glands to prevent additional glucocorticoid secretion (Figure 17.6). Q: By allowing blood levels of a hormone to be regulated within a narrow range, feedback loops contribute to maintaining what state? Choices: - hypothesis - hibernation - consciousness - homeostasis A:
homeostasis