*Question*
Answer the following question given this paragraph: Surface mining is used to obtain mineral ores that are near the surface. Blasting breaks up the soil and rocks that contain the ore. Enormous trucks haul the broken rocks to locations where the ores can be removed. Surface mining includes open-pit mining, quarrying, and strip mining. Q: What type pf mining is used to obtain mineral ores that are near the surface? Choices: - multi-layered mining - function mining - core mining - surface mining A:
**Answer**
surface mining

*Question*
Answer the following question given this paragraph: The structure of the different types of blood vessels reflects their function or layers. There are three distinct layers, or tunics, that form the walls of blood vessels (Figure 40.16). The first tunic is a smooth, inner lining of endothelial cells that are in contact with the red blood cells. The endothelial tunic is continuous with the endocardium of the heart. In capillaries, this single layer of cells is the location of diffusion of oxygen and carbon dioxide between the endothelial cells and red blood cells, as well as the exchange site via endocytosis and exocytosis. The movement of materials at the site of capillaries is regulated by vasoconstriction, narrowing of the blood vessels, and vasodilation, widening of the blood vessels; this is important in the overall regulation of blood pressure. Veins and arteries both have two further tunics that surround the endothelium: the middle tunic is composed of smooth muscle and the outermost layer is connective tissue (collagen and elastic fibers). The elastic connective tissue stretches and supports the blood vessels, and the smooth muscle layer helps regulate blood flow by altering vascular resistance through vasoconstriction and vasodilation. The arteries have thicker smooth muscle and connective tissue than the veins to accommodate the higher pressure and speed of freshly pumped blood. The veins are thinner walled as the pressure and rate of flow are much lower. In addition, veins are structurally different than arteries in that veins have valves to prevent the backflow of blood. Because veins have to work against gravity to get blood back to the heart, contraction of skeletal muscle assists with the flow of blood back to the heart. Q: Three distinct layers or tunics form the walls of what structures; the first is a smooth, inner lining of endothelial cells in contact with the red blood cells? Choices: - lungs - white blood cells - alveoli - blood vessels A:
**Answer**
blood vessels

*Question*
Answer the following question given this paragraph: Saturated hydrocarbons are given the general name of alkanes . The name of specific alkanes always ends in - ane . The first part of the name indicates how many carbon atoms each molecule of the alkane has. The smallest alkane is methane. It has just one carbon atom. The next largest is ethane, with two carbon atoms. The chemical formulas and properties of methane, ethane, and several other alkanes are listed in Table below . The boiling and melting points of alkanes are determined mainly by the number of carbon atoms they have. Alkanes with more carbon atoms generally have higher boiling and melting points. Q: What is the general name for saturated hydrocarbons? Choices: - petrolatums - enzymes - halides - alkanes A:
**Answer**
alkanes

*Question*
Answer the following question given this paragraph: The endoplasmic reticulum (ER) is an organelle that helps make and transport proteins and lipids. It's made of folded membranes. Bits of membrane can pinch off to form tiny sacs called vesicles. The vesicles carry proteins or lipids away from the ER. Q: What is the name of the organelle that helps make and transport proteins and lipids? Choices: - plasma membrane - nucleus - mitochondria - endoplasmic reticulum A:
**Answer**
endoplasmic reticulum