Answer the following question given this paragraph: Some reactions need extra help to occur quickly. They need another substance called a catalyst. A catalyst is a substance that increases the rate of a chemical reaction. A catalyst isn't a reactant, so it isn't changed or used up in the reaction. Therefore, it can catalyze many other reactions. Q: Some reactions need extra help to occur quickly. they need another substance called what? Choices: - neurotransmitter - protein - hormone - a catalyst A:
a catalyst
(Question)
Answer the following question given this paragraph: Frogs typically lay their eggs in puddles, ponds, or lakes. Their larvae, or tadpoles , have gills, a tail, but no legs, and need to live in water. If fact, they are quite similar to a fish. Tadpoles develop into adult frogs in water ( Figure below ). During this transformation, they develop lungs, lose their tails and form their four legs. Q: What to tadpoles develop into? Choices: - toads - mosquitos - snakes - frogs A:
(Answer)
frogs
Ques: Answer the following question given this paragraph: The Uterine Tubes The uterine tubes (also called fallopian tubes or oviducts) serve as the conduit of the oocyte from the ovary to the uterus (Figure 27.14). Each of the two uterine tubes is close to, but not directly connected to, the ovary and divided into sections. The isthmus is the narrow medial end of each uterine tube that is connected to the uterus. The wide distal infundibulum flares out with slender, finger-like projections called fimbriae. The middle region of the tube, called the ampulla, is where fertilization often occurs. The uterine tubes also have three layers: an outer serosa, a middle smooth muscle layer, and an inner mucosal layer. In addition to its mucus-secreting cells, the inner mucosa contains ciliated cells that beat in the direction of the uterus, producing a current that will be critical to move the oocyte. Following ovulation, the secondary oocyte surrounded by a few granulosa cells is released into the peritoneal cavity. The nearby uterine tube, either left or right, receives the oocyte. Unlike sperm, oocytes lack flagella, and therefore cannot move on their own. So how do they travel into the uterine tube and toward the uterus? High concentrations of estrogen that occur around the time of ovulation induce contractions of the smooth muscle along the length of the uterine tube. These contractions occur every 4 to 8 seconds, and the result is a coordinated movement that sweeps the surface of the ovary and the pelvic cavity. Current flowing toward the uterus is generated by coordinated beating of the cilia that line the outside and lumen of the length of the uterine tube. These cilia beat more strongly in response to the high estrogen concentrations that occur around the time of ovulation. As a result of these mechanisms, the oocytegranulosa cell complex is pulled into the interior of the tube. Once inside, the muscular contractions and beating cilia move the oocyte slowly toward the uterus. When fertilization does occur, sperm typically meet the egg while it is still moving... Q: What anatomical structure serves as the conduit of the oocyte from the ovary to the uterus? Choices: - urethra - ureters - nephrons - uterine tubes A:
Ans: uterine tubes
(Q).
Answer the following question given this paragraph: Infectious diseases caused by viruses include the common cold, influenza, and acquired immunodeficiency syndrome (AIDS) and are among the most significant health problems in our society. Viruses are infectious agents far smaller and simpler than bacteria that are composed of a tightly packed central core of nucleic acids enclosed in a protective shell. The shell consists of layers of one or more proteins and may also have lipid or carbohydrate molecules on the surface. Because of their simplicity, viruses must invade the cells of other organisms to be able to reproduce. Viruses are visible only under an electron microscope. They come in a variety of shapes, ranging from spherical to rod shaped. The fact that they contain either deoxyribonucleic acid (DNA) or ribonucleic acid (RNA)but never bothallows them to be divided into two major classes: DNA viruses and RNA viruses (Figure 19.17 "Viruses"). Figure 19.17 Viruses. Q: Culprits in the common cold and aids, what infectious agents are far smaller and simpler than bacteria? Choices: - poisons - pathogens - parasites - viruses A:
(A).
viruses
Ques:Answer the following question given this paragraph: Many chemical reactions and physical processes release energy that can be used to do other things. When the fuel in a car is burned, some of the released energy is used to power the vehicle. Free energy is energy that is available to do work. Spontaneous reactions release free energy as they proceed. Recall that the determining factors for spontaneity of a reaction are the enthalpy and entropy changes that occur for the system. The free energy change of a reaction is a mathematical combination of the enthalpy change and the entropy change. Q: Spontaneous reactions release what type of energy, meaning it is available to do work? Choices: - potential energy - radioactive energy - kinetic energy - free energy A:

Ans:free energy
Question: Answer the following question given this paragraph: In this lesson, you learned that electromagnetic waves are transverse waves. Like other transverse waves, electromagnetic waves have certain properties. Q: What kind of waves are electromagnetic waves? Choices: - amplitude - curved - inverse - transverse A:
Answer:
transverse