Properties of Water
What property of water allows it to form hydrogen bonds with other water molecules and other polar substances?
Water's property of cohesion allows it to form hydrogen bonds with other water molecules and other polar substances.
What are the four main classes of macromolecules found in living organisms?
The four main classes of macromolecules are carbohydrates, lipids, proteins, and nucleic acids.
Which enzyme is responsible for unwinding the DNA double helix during DNA replication?
Answer: C) DNA helicase
Question: During which phase of the cell cycle does DNA replication occur?
Answer: B) Interphase
Question: Which scientist proposed the theory of evolution by natural selection?
Answer: B) Charles Darwin
Describe the significance of water's high specific heat capacity in biological systems.
Water's high specific heat capacity allows it to absorb and release large amounts of heat with minimal temperature change, providing stability to temperature-sensitive biological systems.
Describe the general structure and function of carbohydrates in living organisms.
Carbohydrates are composed of carbon, hydrogen, and oxygen in a 1:2:1 ratio. They serve as a primary source of energy and provide structural support in cells. Examples include glucose, cellulose, and glycogen.
During transcription, which enzyme synthesizes RNA using a DNA template?
Answer: C) RNA polymerase
Question: How many daughter cells are produced at the end of mitosis in a diploid cell?
Answer: A) Two
Question: What is the term for the process by which unrelated species evolve similar traits due to similar environmental pressures?
Answer: A) Convergent evolution
Explanation: Convergent evolution occurs when unrelated species develop similar traits in response to similar environmental pressures, such as the development of wings in birds and bats for flight.
How does the property of adhesion contribute to the process of capillary action in plants?
Adhesion causes water molecules to be attracted to the walls of narrow tubes, such as those found in plant xylem, allowing water to defy gravity and move upward through the plant in a process called capillary action.
Explain the difference between saturated and unsaturated fatty acids, and discuss their implications for human health.
Saturated fatty acids have no double bonds between carbon atoms and are typically solid at room temperature. Unsaturated fatty acids have one or more double bonds and are usually liquid at room temperature. High consumption of saturated fats is associated with increased risk of cardiovascular diseases, while unsaturated fats, especially omega-3 fatty acids, are considered beneficial for heart health.
Question: In the genetic code, a sequence of three nucleotides on mRNA that specifies a particular amino acid is called a:
Answer: A) Codon
Question: Which of the following accurately describes the ploidy of daughter cells produced in meiosis II?
Answer: B) Haploid
Question: What is an example of a vestigial structure in humans?
A) Appendix
Explanation: The human appendix is considered a vestigial structure, as it appears to have lost its original function over evolutionary time.
Discuss the role of water as a solvent in biological systems, considering its polarity and ability to dissolve a wide range of substances.
Water's polarity allows it to dissolve a variety of substances, making it an essential solvent in biological systems. Its ability to form hydration shells around ions and molecules facilitates chemical reactions and the transport of nutrients and waste in organisms.
Describe the central dogma of molecular biology and the roles of DNA and RNA in the process of protein synthesis.
The central dogma states that DNA is transcribed into RNA, which is then translated into proteins. During transcription, RNA polymerase synthesizes mRNA using DNA as a template. In translation, ribosomes read the mRNA sequence and assemble amino acids into a polypeptide chain according to the genetic code. DNA serves as the hereditary material, while RNA acts as an intermediary molecule in protein synthesis.
Question: Which factor is responsible for recruiting charged tRNA molecules to the ribosome during translation?
Answer: B) Elongation factor
Question: What is the role of crossing over in meiosis?
Answer: B) It increases genetic diversity by exchanging genetic material between homologous chromosomes.
Question: Which type of selection favors individuals at both extremes of the phenotypic range?
Answer: C) Disruptive selection
Explanation: Disruptive selection favors individuals at both extremes of the phenotypic range, leading to the divergence of traits within a population.
Explain how water's high surface tension is related to the cohesive properties of water molecules.
Water molecules at the surface are attracted to each other and form stronger hydrogen bonds with neighboring molecules, creating surface tension. This cohesion at the surface allows some organisms, like certain insects, to walk on water.
Discuss the structural diversity and biological significance of lipids in living organisms.
Lipids are diverse molecules characterized by their hydrophobic nature. They include triglycerides for energy storage, phospholipids for cell membrane structure, steroids for hormone regulation, and waxes for waterproofing and protection.
Question: How does gene expression differ between prokaryotic and eukaryotic cells in terms of transcription and translation?
A) Transcription and translation occur simultaneously in prokaryotes.
Question: In which phase of meiosis do homologous chromosomes separate?
Answer: C) Anaphase I
Question: What term describes the process by which two species evolve in response to changes in each other over time?
Answer: C) Coevolution
Explanation: Coevolution is the process by which two species evolve in response to changes in each other over time, often resulting in a close ecological relationship such as mutualism or predator-prey dynamics.