What is a hypothetical explanation for an occurrence that is based on prior knowledge called?
A. Independent variable
B. Dependent variable
C. Trial
D. Hypothesis
A hypothesis is the use of prior knowledge in order to provide a hypothetical explanation for why something may or may not occur. A hypothesis can be proved wrong or right based on the results of the experiment and repeated trials.
Therefore, the Correct Answer is D.
More Questions on TEAS 7 Science
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Q #1: Which of the following answers shows CH4 +2O2=CO2 +H2O as balanced?
A. CH4 + 2O2 = 2CO2 + 2H2O
B. 2CH4 + 4O2 = 2CO2 + H2O
C. 2CH4 + O2 = 2CO2 + H2O
D. CH4 + 2O2 = CO2 + 2H2O
Answer Explanation
For the formula CH4 + 2O2 = CO2 + H2O to be balanced there must be an equal number of molecules on both the reactant and product sides. In this case, for the formula to be balanced, a coefficient of a 2 needs to be placed in front of the O2 and the H2O molecules. This would make both the reactant and product sides have one carbon, four hydrogens, and four oxygens
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Q #2: Enzymes catalyze biochemical reactions by ________
A. Lowering the potential energy of the products
B. Separating inhibitors from products
C. Forming a complex with the products
D. Lowering the activation energy of the reaction
Answer Explanation
Enzymes act as catalysts for biochemical reactions. A catalyst is not consumed in a reaction, but rather lowers the activation energy for that reaction. The potential energy of the substrate and the product remain the same, but the activation energy-the energy needed to make the reaction progress can be lowered with the help of an enzyme.
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Q #3: Which of the following are formed when the plasma membrane surrounds a particle outside of the cell?
A. Golgi bodies
B. Rough endoplasmic reticulum
C. Secretory vesicles
D. Endocytic vesicles
Answer Explanation
Endocytosis is a process by which cells absorb larger molecules or even tiny organisms, such as bacteria, that would not be able to pass through the plasma membrane. Endocytic vesicles containing molecules from the extracellular environment often undergo further processing once they enter the cell.
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Q #4: Which of the following are examples of homeostatic mechanisms?
A. Increasing heart rate when blood pressure is low, Consuming excess calories to gain weight
B. Lifting weights to increase muscle mass
C. Shivering when the body temperature falls
D. Shivering when the body temperature falls, Secreting insulin to decrease blood sugar concentration, Increasing heart rate when blood pressure is low
Answer Explanation
Homeostatic mechanisms are involuntary actions by organs, glands, tissues and cells to maintain balance within the body. For example, if a person becomes dehydrated, the kidneys will retain fluid by decreasing urine output.
Consuming excess calories and lifting weights are not involuntary actions, nor do they maintain the body in its baseline state. Rather, they are actions specifically taken to move the body away from its baseline.
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Q #5: What is the name for the physical presentation of an organism's genes?
A. Phenotype
B. Species
C. Phylum
D. Genotype
Answer Explanation
Phenotype is the physical presentation of an organism's genes. In other words, the phenotype is the physical characteristics of the organism. Phenotype is often contrasted with genotype, the genetic makeup of an organism. The genotype of the organism is not visible in its presentation, although some of the characteristics encoded in the genes have to do with physical presentation. A phylum is a group of classes that are closely related. A species is a group of like organisms that are capable of breeding together and producing similar offspring.
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Q #6: When animals eat, insulin is released from the pancreas, stimulating glucose uptake by the liver. When glucose levels drop, the pancreas reduces insulin release. This is an example of which mechanism for maintaining homeostasis?
A. Negative feedback
B. Positive feedback
C. Stress response
D. Parasympathetic regulation
Answer Explanation
Maintaining homeostasis means that conditions are kept stable and relatively constant. Negative feedback is a mechanism used to reverse or minimize changes in a system. In this example, negative feedback is used to keep the body's glucose and insulin levels stable. Positive feedback (B) is a mechanism that Increases changes in a system. A stress response (C) describes the body's reaction to threats or pressures. Parasympathetic regulation (D) refers to activities of the nervous system, including slowing the heart rate and boosting Intestinal activity.
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Q #7: What types of reaction is Cu (s) + 2AgNO3(aq) → 2Ag(s) + Cu(NO3)2(aq)?
A. Single replacement
B. Double replacement
C. Synthesis
D. Decomposition
Answer Explanation
This is a single replacement reaction in which copper replaces silver. The copper combines with the nitrate ions, and the silver precipitates out. Single replacement reactions have the general form of
A + BC →
AC + B. Double replacement reactions have the general form of AB + CD→
AD + CB. Synthesis reactions have the general form of A + B →
AB. Decomposition reactions have the general form AB→
A+B. -
Q #8: A doctor needs to convince his boss to approve a test for a patient. Which statement below best communicates a scientific argument that justifies the need for the test?
A. The patient looks like he needs this test.
B. The doctor feels that the patient needs this test.
C. The patient's symptoms and health history suggest that this test will enable the correct diagnosis to help the patient.
D. The patient has excellent insurance that will pay for several tests, and the doctor would like to run as many tests as possible.
Answer Explanation
A scientific argument should be based on measurable and observable facts such as the patient's current symptoms and health history. Discussing the patient's appearance or the doctor's feelings does not communicate a scientific argument. While insurance may be a factor in most healthcare systems, the status of the patient's Insurance does not communicate a scientific argument that justifies the need for the test
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Q #9: Which is NOT a type of protein?
A. Fibrous
B. Membrane
C. Globular
D. Unsaturated
Answer Explanation
There are three types of proteins: fibrous, membrane, and globular. Fibrous or structural proteins consist of collagen, elastin, and keratin. Membrane proteins are interactive and anchored to a membrane. Globular proteins consist of functional proteins like enzymes, hemoglobin, and insulin.
Therefore unsaturated is the correct answer.
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Q #10: What is a hypothetical explanation for an occurrence that is based on prior knowledge called?
A. Independent variable
B. Dependent variable
C. Trial
D. Hypothesis
Answer Explanation
A hypothesis is the use of prior knowledge in order to provide a hypothetical explanation for why something may or may not occur. A hypothesis can be proved wrong or right based on the results of the experiment and repeated trials.
