Water
What property of water makes it essential for life?
Its ability to act as a universal solvent, facilitating chemical reactions and transporting nutrients and waste in organisms (accept other reasonable responses)
Why is DNA considered the genetic material of all living organisms?
DNA is considered the genetic material of all living organisms because it carries the hereditary information necessary for the development, growth, and functioning of cells and organisms.
What were the conditions on early Earth that led to the pre-biotic formation of carbon compounds?
The conditions on early Earth, such as the presence of reducing atmosphere, volcanic activity, and energy sources like lightning and UV radiation, likely led to the pre-biotic formation of carbon compounds.
What chemical properties of carbon allow for the formation of diverse compounds in life?
The chemical properties of carbon, such as its ability to form stable covalent bonds and create diverse molecular structures, allow for the formation of complex and varied compounds in living organisms.
What is the mechanism that drives evolutionary change?
Natural selection
Explain the significance of hydrogen bonds in water molecules
Hydrogen bonds in water molecules contribute to the cohesion between water molecules, high specific heat capacity, and high heat of vaporization, which are important for maintaining stable temperatures and regulating the climate.
What is the role of the sugar-phosphate backbone in DNA and RNA?
The sugar-phosphate backbone in DNA and RNA provides structural stability and serves as a platform for the attachment of nucleotide bases, which encode genetic information and allow for the formation of complementary base pairs.
What evidence supports the origin of carbon compounds?
Evidence supporting the origin of carbon compounds includes laboratory experiments simulating early Earth conditions, the detection of organic molecules in meteorites and interstellar space, and the observation of complex organic molecules in various environments.
How are macromolecules produced by condensation reactions in cells?
Macromolecules are produced by condensation reactions, where monomers are joined together by the removal of a water molecule. This process is catalyzed by enzymes and occurs in cells.
Explain the roles of mutation and sexual reproduction in generating variation for natural selection.
They contribute to genetic diversity on which natural selection acts.
How does cohesion of water molecules impact organisms?
The cohesion of water molecules allows for surface tension, capillary action, and the formation of droplets, which are crucial for the transportation of water and nutrients in plants and the movement of blood in animals.
How is RNA formed from nucleotide monomers?
RNA is formed from nucleotide monomers through a process called transcription, where an RNA molecule is synthesized using a DNA template. The RNA molecule carries genetic information and can be involved in protein synthesis.
How are vesicles formed by fatty acids related to the origin of cells?
Vesicles formed by fatty acids can create a semi-permeable boundary that separates the internal environment from the external surroundings, potentially allowing for the concentration and organization of molecules necessary for early cellular processes.
What is the structure of cellulose and its function in plants?
Cellulose is a polysaccharide made up of glucose monomers linked by beta-glycosidic bonds. It forms a rigid structure in plant cell walls, providing support and strength to the plant.
How do overproduction of offspring and competition for resources promote natural selection?
They lead to a struggle for survival and reproduction.
Describe how adhesion of water to polar or charged materials affects organisms.
The adhesion of water to polar or charged materials enables water to be transported against gravity in plants through capillary action and helps organisms adhere to surfaces, such as insects walking on water.
Explain the differences between DNA and RNA.
DNA and RNA differ in their sugar component (deoxyribose in DNA and ribose in RNA), the presence of thymine in DNA (replaced by uracil in RNA), and their respective roles (DNA carries genetic information, while RNA is involved in protein synthesis).
How do scientists estimate dates of the first living cells and the last universal common ancestor?
Scientists estimate the dates of the first living cells and the last universal common ancestor through various methods, including fossil records, molecular clock analysis, and geological dating techniques.
Discuss the differences between saturated, monounsaturated, and polyunsaturated fatty acids.
Saturated fatty acids have single bonds between carbon atoms, monounsaturated fatty acids have one double bond, and polyunsaturated fatty acids have multiple double bonds. These differences affect the physical properties and health implications of these fatty acids.
Give an example of an abiotic factor that can act as a selection pressure.
Climate or temperature.
How do the solvent properties of water support metabolic processes?
The solvent properties of water allow it to dissolve various molecules, such as ions and polar compounds, facilitating metabolic reactions and transportation of nutrients, wastes, and signaling molecules in organisms.
What is the significance of the diversity of possible DNA base sequences?
The diversity of possible DNA base sequences allows for the storage of a vast amount of genetic information, which contributes to the genetic variation and adaptability of organisms.
What evidence supports the evolution of the last universal common ancestor near hydrothermal vents?
Evidence supporting the evolution of the last universal common ancestor near hydrothermal vents includes the discovery of microbial life in similar extreme environments, the production of organic molecules in laboratory simulations of hydrothermal vent conditions, and genetic comparisons among modern organisms suggesting a shared ancestry.
How are triglycerides and phospholipids formed in cells?
Triglycerides are formed by the esterification of glycerol with three fatty acid molecules. Phospholipids are formed by the esterification of glycerol with two fatty acid molecules and a phosphate group. These processes occur in cells and are essential for energy storage and the structure of cell membranes.
What is the basis for natural selection in individuals?
Differences in traits (variation), survival, and reproduction.