FREE ATDH Biology and General Chemistry Questions and Answers
A sample containing helium gas at 0.20 atm compresses so that its volume is halved at a constant temperature. What is the new pressure in atmospheres?
Explanation:
When a gas is compressed at a constant temperature, its pressure increases inversely to the volume. So, if the volume is halved, the pressure doubles.
In this case, if the initial pressure is 0.20 atm and the volume is halved, the new pressure becomes 0.40 atm, as the pressure doubles when the volume is halved.
Which is the strongest attractive interaction in pure ethanol?
Explanation:
In pure ethanol, the strongest attractive interaction is hydrogen bonding. This occurs because ethanol molecules contain hydrogen atoms bonded to highly electronegative oxygen atoms. These hydrogen atoms can form hydrogen bonds with other ethanol molecules, where the partially positive hydrogen atom of one molecule is attracted to the partially negative oxygen atom of another molecule. This type of bonding is stronger than dipole-dipole forces, London dispersion forces, and ionic bonding in the context of pure ethanol.
What is the major function of the Golgi apparatus?
Explanation:
The Golgi apparatus is responsible for modifying, sorting, and packaging proteins and lipids into vesicles for delivery to targeted destinations within or outside the cell. This includes sorting secretory proteins destined for secretion outside the cell and membrane proteins that are integrated into the cell membrane or other cellular compartments.
Which of the following is a noble gas?
Explanation:
Helium is a noble gas. Noble gases are a group of chemical elements characterized by their low reactivity under normal conditions. They are found in group 18 of the periodic table and include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). Noble gases have full valence electron shells, making them stable and unreactive with other elements. Helium, specifically, is the second lightest and second most abundant element in the universe, commonly used in balloons, airships, and cryogenic applications.
Which condition is characterized by a symbiotic association between two species, without harm to either, but with some benefit to both symbionts?
Explanation:
Mutualism is a type of symbiotic relationship between two species in which both organisms benefit from the association. In mutualism, neither species is harmed, and both receive some form of benefit. This contrasts with predation, where one organism benefits at the expense of the other, and parasitism, where one organism benefits while the other is harmed. Commensalism, while similar to mutualism, involves one organism benefiting while the other is unaffected.
Which type of RNA binds an amino acid and carries it to the ribosome?
Explanation:
Transfer RNA (tRNA) is the type of RNA that binds to specific amino acids and carries them to the ribosome during protein synthesis. Each tRNA molecule has an anticodon region that recognizes a specific codon on the mRNA (messenger RNA) and an attachment site for a specific amino acid. This allows tRNA to "translate" the information encoded in the mRNA into the corresponding sequence of amino acids in the growing polypeptide chain at the ribosome.
To maintain homeostasis, a drop in body temperature in a mammal is generally followed by:
Explanation:
When a mammal experiences a drop in body temperature, one of the primary responses to maintain homeostasis is shivering. Shivering is a physiological mechanism in which rapid muscle contractions generate heat, helping to increase body temperature back to the normal range. This response helps to counteract the decrease in temperature and restore equilibrium within the body.
Which might have an RNA genome?
Explanation:
Viruses can have RNA genomes. Unlike bacteria, fungi, and protists, which typically have DNA genomes, viruses can contain either RNA or DNA as their genetic material. Some viruses, known as RNA viruses, have RNA genomes, while others have DNA genomes.
What is the formula for sulfuric acid?
Explanation:
Sulfuric acid is represented by the chemical formula H2SO4. It is a strong mineral acid with the chemical formula H2SO4. It is soluble in water at all concentrations, and its aqueous solution is known as "battery acid" or "diluted sulfuric acid." It is one of the most important industrial chemicals, primarily used in the production of fertilizers, explosives, detergents, and various other chemicals.
Which organelle is responsible for cellular respiration?
Explanation:
The mitochondrion is responsible for cellular respiration, a process that produces ATP (adenosine triphosphate), the cell's main energy currency. Within the mitochondria, various enzymes and metabolic pathways convert glucose and oxygen into ATP through a series of biochemical reactions. This process provides energy for cellular activities and is essential for the survival and functioning of eukaryotic cells.
What is the primary function of the chloroplast in plant cells?
Explanation:
The chloroplast's primary function in plant cells is photosynthesis, the process by which plants convert light energy into chemical energy in the form of glucose. Chloroplasts contain chlorophyll, a green pigment that captures light energy from the sun. This energy is used to drive the synthesis of glucose from carbon dioxide and water, releasing oxygen as a byproduct. Photosynthesis is vital for the production of organic compounds that sustain plant growth and provide energy for all living organisms.