Properties of life and cell theory
What are the three domains of life?
What is Bacteria, Eukarya, and Archaea?
Which of the subatomic particles CANNOT change in number without changing the identity of the element itself?
The number of protons in an atom determines the element's identity; changing the number of protons changes the element.
What is the difference between quantitative and qualitative data?
What is the importance of genetic variation in evolution?
Genetic variation provides the raw material for natural selection, as it allows for different traits to be favored in different environments, leading to evolutionary changes over time.
What is the difference between covalent and ionic bonds?
What property of water molecules allows it to retain surface tension?
Surface tension is due to the cohesive forces between water molecules. These cohesive forces create a "skin" on the surface of the water, allowing it to resist external forces.
Write the equation for pH.
The equation for pH is: pH=−log[H+]
What do Prokaryotic and Eukaryotic cells have in common?
DNA, Order, regulation, reproduction, growth & development, evolutionary adaptation, energy processing, and response to environment
What are the differences between an atom, an element, and an isotope, and how are they related?
Differentiate between independent vs dependent variable, and controls.
Question: What are the differences between independent variables, dependent variables, and controls?
What is the role of adaptation in Darwin’s theory of evolution?
Adaptation occurs when traits that enhance an organism’s survival and reproductive success become more common in a population over generations due to natural selection.
In what circumstances will an ionic bond form?
An ionic bond forms when there is a large difference in electronegativity between two atoms, typically between a metal and a non-metal. The metal loses electrons to become a positively charged ion, while the non-metal gains those electrons to become a negatively charged ion.
What is the difference between temperature and heat?
What is one “mole” and what do we use a mole to quantify?
One mole is 6.022×10236.022 \times 10^{23}6.022×1023 entities (atoms, molecules, etc.). It is used to quantify the amount of a substance in terms of the number of particles it contains.
What is one thing that makes a Eukaryotic cell different from a prokaryotic cell?
Eukaryotic cells have a membrane-bound nucleus and membranes, while Prokaryotic cells do not.
What is the number of protons in the nucleus of an atom tell us about the atom?
The atomic number of an element is the number of protons in the nucleus of its atoms.
Why must the methods of a research study be repeatable?
The methods of a research study must be repeatable to ensure that the results are reliable and can be verified by other researchers. Repeatability helps confirm that the findings are consistent and not due to random chance or experimental error.
What is common descent?
Common descent is the concept that all living organisms share a common ancestor and have diverged from this ancestral species over time through the process of evolution.
What determines whether a covalent bond will be polar?
A covalent bond is polar if there is a significant difference in electronegativity between the two atoms involved. The atom with the higher electronegativity will attract the shared electrons more strongly, creating a partial negative charge on that atom and a partial positive charge on the other.
Define specific heat.
Specific heat is the amount of heat required to raise the temperature of one gram of a substance by one degree Celsius.
Define acid and base.
What are the four recognized Kingdoms of the Eukarya Domain?
1. Plantae
2. Animalia
3. Fungi
4. Protists
What is the sum of the number of protons and neutrons in an atom's nucleus?
The mass number is the total number of protons and neutrons in an atom's nucleus.
How is the word “theory” defined in scientific terms?
In science, a theory is a well-substantiated explanation of an aspect of the natural world that has been repeatedly tested and confirmed through observation and experimentation. It integrates a range of facts and hypotheses into a coherent framework.
What is the evidence supporting the endosymbiotic origin of mitochondria and chloroplasts?
Evidence includes the presence of their own circular DNA, double membranes, and ribosomes similar to those found in prokaryotes, as well as their ability to replicate independently within the cell.
In what circumstances will a covalent bond be non-polar?
A covalent bond is non-polar when the two atoms involved have similar or identical electronegativities. The electrons are shared equally, resulting in no partial charges on the atoms. Non-polar covalent bonds typically occur between identical atoms (e.g., H₂, O₂) or between atoms with similar electronegativities.
Define heat of vaporization.
Heat of vaporization is the amount of heat required to convert one gram of a liquid into a gas at its boiling point without changing its temperature.
pH is measured on a log scale—explain what one change on this log scale (for example, an increase in pH from 3 to 4) means for the change in concentration of H⁺ in the solution.
An increase in pH by 1 unit represents a tenfold decrease in the concentration of hydrogen ions [H⁺]. For example, a solution with pH 3 has ten times the concentration of H⁺ ions compared to a solution with pH 4.
Does Cell Theory provide a structural or functional definition of life?
Cell Theory provides a structural definition of life, focusing on the idea that all living things are composed of cells.
Define valence, valence shell, and valence electrons
What kinds of conclusions can be drawn from observational studies compared to experimental studies, and how do these study designs differ?
Difference: Observational studies do not involve manipulation of variables and often deal with natural conditions, while experimental studies involve controlled manipulation of variables to test hypotheses.
What is the explanation for the similarities between mitochondria, chloroplasts, and prokaryotic cells according to the serial endosymbiosis theory?
The similarities are explained by the theory suggesting that mitochondria and chloroplasts are descendants of free-living prokaryotes that were engulfed by a host cell, leading to a mutualistic relationship and the integration of these prokaryotes into the eukaryotic cell as organelles.
Order Hydrogen, covalent, Ionic, and Van Der Walls interactions in order of strongest to weakest.
what is Ionic, Covalent, Hydrogen, and van der Waals interactions?
How does water’s high specific heat contribute to its ability to sustain life?
Water’s high specific heat allows it to absorb and release large amounts of heat with only small changes in its own temperature. This helps maintain stable temperatures in organisms and environments, supporting life by protecting against extreme temperature fluctuations.
What is a buffer?
A buffer is a solution that resists changes in pH when small amounts of an acid or base are added. It typically consists of a weak acid and its conjugate base or a weak base and its conjugate acid.
What are the three main tenets of Cell Theory?
What does it mean if an atom of an element is “ionized”?
When an atom is ionized, it has gained or lost one or more electrons, resulting in a net electrical charge.
What is something important when conducting research?
Using reliable sources of information, avoid information from blogs and out of dated textbooks.
What is a major difference between Darwin’s theory of evolution and the serial endosymbiosis theory?
Darwin’s theory of evolution focuses on the mechanisms of natural selection and adaptation over time, while the serial endosymbiosis theory explains the origin of eukaryotic cells through symbiotic relationships with prokaryotic cells.
Differentiate between "reactants" and "products" in a chemical reaction.
What is the equation for the natural ionization (or dissociation) of water molecules?
The equation for the natural ionization of water is: H2O⇌H++OH−\text{H}_2\text{O} \rightleftharpoons \text{H}^+ + \text{OH}^-H2O⇌H++OH−
Describe the “law of mass action” in the context of buffer systems.
The law of mass action states that the position of equilibrium in a reversible reaction is determined by the concentrations of reactants and products. In buffer systems, the law of mass action helps maintain pH stability by shifting the equilibrium between the weak acid and its conjugate base to counteract pH changes.
What are some life-like entities that are not considered living under Cell Theory?
Viruses are considered life-like entities because they can reproduce and evolve, but they are not considered living organisms under Cell Theory because they do not consist of cells and require a host cell to replicate.
What is electronegativity?
pt.2 Out of C, N, O, and H, which two are the most electronegative? Which two elements have the most similar electronegativity?
Electronegativity is the measure of an atom's ability to attract and hold onto electrons in a chemical bond.
What are the steps of the scientific method in order?
Observation, prediction, hypothesis, Experiment, collect data, analyze data, conclusion, report results.
How is the emergence of antibiotic resistance in bacteria an example
of rapid natural selection?
Within any bacterial population, there is genetic variation. Some bacteria naturally possess or acquire mutations that provide resistance to antibiotics. This variation arises through random genetic mutations or through the acquisition of resistance genes from other bacteria.
bacteria that are resistant to antibiotics survive and reproduce in the presence of the drug, while those that are not resistant are killed. As a result, the proportion of resistant bacteria increases rapidly in the population, as they reproduce and pass on their resistance traits to their offspring.
Bacteria reproduce rapidly, often within hours, which allows for quick changes in their populations. When exposed to antibiotics, the selection pressure is immediate and intense, leading to rapid evolution of resistance within a very short period compared to the timescales of many other evolutionary processes.
What is a cation?
Pt. 2 what is an anion?
A cation is a positively charged ion. It forms when an atom loses one or more electrons, resulting in a net positive charge. For example, a sodium atom (Na) that loses one electron becomes a sodium cation (Na⁺).
An anion is a negatively charged ion. It forms when an atom gains one or more electrons, resulting in a net negative charge. For example, a chlorine atom (Cl) that gains one electron becomes a chloride anion (Cl⁻).
What is the concentration of hydrogen ions [H⁺] in pure water? Write the number in scientific notation.
In pure water, the concentration of hydrogen ions [H⁺] is 1×10−71 \times 10^{-7}1×10−7 moles per liter.
Given the equation of our blood’s buffering system, predict how the addition of an acid or a base to the bloodstream would impact the equilibrium of the reaction, and how the reaction may “shift” to reestablish dynamic equilibrium.
The blood’s buffering system is represented by the equation: H2CO3⇌H++HCO3−\text{H}_2\text{CO}_3 \rightleftharpoons \text{H}^+ + \text{HCO}_3^-H2CO3⇌H++HCO3−