Base your answer on the graph and on your knowledge of biology. Which is a true statement about the relationship between pH and enzyme action?
A. All enzymes work best at a neutral pH.
B. Adding more acid does not affect the rate of activity of an enzyme.
C. Enzymes function only in a pH range of 4.0 to 5.5.
D. The activity of an enzyme is affected by pH.
Therefore, the Correct Answer is D.
More Questions on TEAS 7 Science
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Q #1: Base your answer on the graph and on your knowledge of biology. Which is a true statement about the relationship between pH and enzyme action?
A. All enzymes work best at a neutral pH.
B. Adding more acid does not affect the rate of activity of an enzyme.
C. Enzymes function only in a pH range of 4.0 to 5.5.
D. The activity of an enzyme is affected by pH.
Answer Explanation
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Q #2: Which of the following indicates the function of sodium bicarbonate released by the pancreas?
A. Sodium bicarbonate inhibits peristalsis
B. Sodium bicarbonate is a protease that digests carbohydrates
C. Sodium bicarbonate stimulates the pyloric sphincter
D. Sodium bicarbonate neutralizes the acidity of chyme
Answer Explanation
Sodium bicarbonate is an alkaline solution, which is released by the pancreas. Chyme is acidic coming from the stomach is neutralized by sodium bicarbonate to protect the duodenum.
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Q #3: Which of these organs is not considered an accessory digestive structure?
A. mouth
B. salivary glands
C. pancreas
D. liver
Answer Explanation
Accessory organs of the digestive system comprise of organs that empty secretions into the alimentary canal. These organs include salivary glands, liver, gallbladder and pancreas. The mount if path of the alimentary canal.
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Q #4: Which of the following best describes veins?
A. thick walled, small lumens, low pressure, lack valves
B. thin walled, large lumens, low pressure, have valves
C. thin walled, small lumens, high pressure, have valves
D. thick walled, large lumens, high pressure, lack valves
Answer Explanation
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Q #5: Nitrogen gas is an extremely stable molecule because its structure contains which of the following?
A. Resonance bonds
B. Ionic bonds
C. Triple covalent bonds
D. Hydrogen bonds
Answer Explanation
The Lewis structure of nitrogen gas is shown below. Triple bonds are stronger than double or single bonds. Therefore, we can infer that the triple bond between the two nitrogen atoms makes nitrogen gas more stable.
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Q #6: The process that moves nutrients into the blood or lymph is
A. digestion
B. ingestion
C. elimination
D. absorption
Answer Explanation
Digestion is the breakdown of large insoluble food molecules into small water-soluble food molecules so that they can be absorbed into the watery blood plasma.
Ingestion is the process of taking food, drink, or another substance into the body by swallowing or absorbing it.
Elimination refers to the removal of indigestible wastes through the anus, in the form of feaces.
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Q #7: Which of these infectious agents do not have nucleic acid?
A. viroids
B. viruses
C. bacteria
D. prions
Answer Explanation
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Q #8: Metabolism of proteins Which of the following substances is excreted by sweat glands in response to the breakdown of proteins and the formation of ammonia?
A. Sebum
B. Urea
C. Lysozymes
D. Water
Answer Explanation
Proteins are nitrogen-based compounds, which when broken down release ammonia. Ammonia is a toxic substance to the body, and sebaceous glands coverts it to urea.
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Q #9: Contraction of the external intercostal muscles causes which of the following to occur?
A. The diaphragm moves downward
B. The rib cage is compressed
C. The thoracic cavity volume decreases
D. The ribs and sternum move upward
Answer Explanation
The intercostal muscles are muscles are located along the ribs. The intercostal muscles assist in respiration mechanically. This allows the expansion and contraction of the thorax.
Contraction of the external intercostal muscle causes the ribs and sternum move upward. -
Q #10: In a plant in which fuzzy leaves (F) are dominant over smooth leaves (f), which of the following crosses will produce only offspring with smooth leaves?
A. Ff x ff
B. Ff x Ff
C. FF x FF
D. ff x ff
Answer Explanation
Crossing is the breeding of parents to produce an offspring. Given that f is a recessive allele of smooth leaves while F is the dominant allele of fuzzy leaves. Therefore, where there is F crossing with f, the offspring will have fuzzy leaves over smooth one.
Therefore, for an offspring to have smooth leaves, ff and ff must cross to produce an offspring with smooth leaves.
