Answer the following question given this paragraph: Scientists use models to help them understand and explain ideas. Models explain objects or systems in a more simple way. Models often only show only a part of a system. The real situation is more complicated. Models help scientists to make predictions about complex systems. Some models are something that you can see or touch. Other types of models use an idea or numbers. Each type is useful in certain ways. Q: What do scientists use to help explain objects or systems in simpler ways? Choices: - theories - measurements - plants - models A:
models
(Question)
Answer the following question given this paragraph: Hormones Hormones are molecular signals that help regulate a number of biochemical processes. Single amino acids and short protein chains are very common types of hormones. For example, insulin is a protein hormone that regulates the amount of glucose present in the bloodstream. Q: What do you call the type of molecular signals that include insulin and that help regulate a number of biochemical processes? Choices: - nerves - acids - enzymes - hormones A:
(Answer)
hormones
Ques: Answer the following question given this paragraph: Cell division is just one of several stages that a cell goes through during its lifetime. The cell cycle is a repeating series of events that include growth, DNA synthesis, and cell division. The cell cycle in prokaryotes is quite simple: the cell grows, its DNA replicates, and the cell divides. In eukaryotes, the cell cycle is more complicated. Q: What is defined as a repeating series of events that include growth, dna synthesis, and cell division? Choices: - photosynthesis - meiosis - puberty - cell cycle A:
Ans: cell cycle
(Q).
Answer the following question given this paragraph: Ionic compounds have positive ions and negative ions. Q: What compound has positive and negative ions? Choices: - hydrocarbon - protein - covalent - ionic A:
(A).
ionic
Ques:Answer the following question given this paragraph: Aging is associated with the death of cells. Give two reasons why cells die. Q: Aging is associated with the death of what? Choices: - proteins - genes - muscles - cells A:

Ans:cells
Answer the following question given this paragraph: Monotreme reproduction is the least risky for the mother. However, eggs are harder to protect than is an embryo or a fetus in a pouch or uterus. Therefore, monotreme offspring may have a lower chance of surviving than the offspring of therian mammals. Q: What kind of mammalian reproduction is risky for the offspring but not the mother? Choices: - asexual - sexual - cactaceae - monotreme A:
monotreme