input: OPTIONS:
- an occluded front
- a stationary front
- a snow day
- a cold front Now, answer this question: Answer the following question given this paragraph: A cold front occurs when a cold air mass runs into a warm air mass. This is shown in Figure below . The cold air mass moves faster than the warm air mass and lifts the warm air mass out of its way. As the warm air rises, its water vapor condenses. Clouds form, and precipitation falls. If the warm air is very humid, precipitation can be heavy. Temperature and pressure differences between the two air masses cause winds. Winds may be very strong along a cold front. Q: What occurs when a cold air mass runs into a warm air mass? A:
A:
output: a cold front

Answer the following question given this paragraph: The first horizon is the "A" horizon. It is more commonly called the topsoil . The topsoil is usually the darkest layer of the soil. It is the layer with the most organic material. Humus forms from all the plant and animal debris that falls to or grows on the ground. The topsoil is also the region with the most biological activity. Many organisms live within this layer. Plant roots stretch down into this layer. The roots help to hold the topsoil in place. Topsoil is needed to grow most crops ( Figure below ). Q: What is the "a" horizon commonly known as? A:

OPTIONS:
- sediment
- core
- crust
- topsoil

Answer: topsoil

Problem: OPTIONS:
- intestines
- liver
- the arteries
- the kidneys
Q: Answer the following question given this paragraph: The kidneys help the body maintain homeostasis in several ways. They filter all the blood in the body many times each day and produce urine. They control the amount of water and dissolved substances in the blood by excreting more or less of them in urine. Q: Which body organ filters the blood in the body and creates urine? A:
Answer: the kidneys

Problem:OPTIONS:
- insulin
- sucrose
- mitochondria
- glucose

Answer the following question given this paragraph: Active transport pumps can also work together with other active or passive transport systems to move substances across the membrane. For example, the sodium-potassium pump maintains a high concentration of sodium ions outside of the cell. Therefore, if the cell needs sodium ions, all it has to do is open a passive sodium channel, as the concentration gradient of the sodium ions will drive them to diffuse into the cell. In this way, the action of an active transport pump (the sodiumpotassium pump) powers the passive transport of sodium ions by creating a concentration gradient. When active transport powers the transport of another substance in this way, it is called secondary active transport. Symporters are secondary active transporters that move two substances in the same direction. For example, the sodiumglucose symporter uses sodium ions to "pull" glucose molecules into the cell. Because cells store glucose for energy, glucose is typically at a higher concentration inside of the cell than outside. However, due to the action of the sodiumpotassium pump, sodium ions will easily diffuse into the cell when the symporter is opened. The flood of sodium ions through the symporter provides the energy that allows glucose to move through the symporter and into the cell, against its concentration gradient. Q: The flood of sodium ions through the symporter provides the energy that allows what to move through the symporter and into the cell? A:
****
A: glucose

Answer the following question given this paragraph: Q: From what did the first proto-oncogenes arise? A:
OPTIONS:
- spores
- carcinogens
- bacteria
- viral infections
viral infections

Answer the following question given this paragraph: What causes puberty to begin? The hypothalamus in the brain "tells" the pituitary gland to secrete hormones that target the testes. The main pituitary hormone involved is luteinizing hormone (LH) . It stimulates the testes to secrete testosterone. Testosterone, in turn, promotes protein synthesis and growth. It brings about most of the physical changes of puberty, some of which are shown in Figure below . In addition to the changes shown below, during puberty male facial hair begins to grow, the shoulders broaden, and the male voice deepens. You can watch an animation of these and other changes that occur in boys during puberty at the Interactive Body link: http://www. bbc. co. uk/science/humanbody/body/interactives/lifecycle/teenagers/ . Q: What hormone, which is associated with luteinizing hormone and male sexuality, helps bring about physical changes in puberty? A:
OPTIONS:
- steroids
- epinephrine
- estrogen
- testosterone

Answer:
testosterone