Understanding Scientific Method and Statistics

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the difference between a hypothesis and a theory?

A hypothesis is broader in scope than a theory.

A hypothesis is a tentative explanation, while a theory is a well-substantiated explanation. (correct)

A hypothesis is a proven fact, while a theory is just a guess.

A theory can be tested, whereas a hypothesis cannot.

Which of the following correctly defines standard deviation?

The average of a dataset.

The same as the mean of a dataset.

The middle value in a dataset when arranged in order.

A measure of how spread out the numbers in a data set are. (correct)

What does an error bar represent on a graph?

The average value of the data point.

The maximum possible error in data collection.

The range of values that a data point can take.

The standard deviation of the data set. (correct)

Which of the following statements is true regarding prokaryotic and eukaryotic cells?

Eukaryotic cells contain membrane-bound organelles, while prokaryotic cells do not. Signup and view all the answers

What is the primary function of ribosomes in a cell?

Protein synthesis. Signup and view all the answers

In a scientific experiment, which of the following would be considered a dependent variable?

The growth of the plant. Signup and view all the answers

What is active transport in cellular biology?

The movement of substances against their concentration gradient using energy. Signup and view all the answers

How would a decrease in the surface area to volume ratio affect a cell?

It would hinder the exchange of materials and waste. Signup and view all the answers

In a comparison of solutions A and B, which solution had more solute dissolved into it?

Solution B, as it lost mass. Signup and view all the answers

What term defines a solution that has a lower concentration of solute compared to another solution?

Hypotonic solution Signup and view all the answers

What aspect of water is primarily responsible for its high surface tension?

Hydrogen bonding between molecules Signup and view all the answers

Which of the following statements correctly describes a difference between saturated and unsaturated fatty acids?

Saturated fatty acids are solid at room temperature. Signup and view all the answers

Which of the following best explains why enzymes are not considered reactants in a reaction?

Enzymes remain unchanged after the reaction. Signup and view all the answers

What is formed during the process of dehydration synthesis?

Water molecules are released. Signup and view all the answers

What defines a hypertonic solution?

It has a higher concentration of solute than the cell. Signup and view all the answers

Which of the following structures is formed by the arrangement of multiple polypeptides?

Quaternary structure Signup and view all the answers

What is the primary function of ATP in cellular processes?

To provide energy for biochemical reactions. Signup and view all the answers

Which of the following is an example of catabolism?

Glycolysis Signup and view all the answers

Study Notes

Scientific Method

General steps of the scientific method are not detailed.

Theories vs. Hypotheses

A hypothesis is a testable explanation for an observation.
A theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Theories are comprehensive and more encompassing than hypotheses.

Scientific Errors vs. Mistakes

A source of scientific error is a flaw in the experimental design or procedure that could lead to inaccurate results. This isn't a human fault but a systemic problem in the procedure itself.
A mistake is an unintentional error by the experimenter or a flaw in execution. Mistakes happen during the experiment.

Mean, Mode, and Median

Mean: The average of a data set.
Mode: The most frequent value in a data set.
Median: The middle value in a sorted data set.

Standard Deviation

Standard deviation measures the spread or dispersion of a data set around the mean.
It provides a more detailed understanding of the data distribution than just looking at the mean.

Error Bars

Error bars show the range of values that likely include the true mean of measured data.
Created by displaying the mean ± standard deviation
Related to standard deviation due to standard deviations inclusion in the measures.

Cell Biology

1.1 - Introduction to Cells

Dependent Variable: Plant growth (c)
Cell Theory:
- All known living things are made up of one or more cells.
- All living cells arise from pre-existing cells by division.
- The cell is the fundamental unit of structure and function in all living organisms.
Small Cell Size: Due to a high surface area to volume ratio; this is essential for efficient exchange of materials with the environment.
Decreased Surface Area to Volume Ratio: Reduced efficiency in nutrient intake and waste removal. Resulting in organelle malfunction, cellular death.
Prokaryotes vs. Eukaryotes:
- Prokaryotes have no membrane-bound organelles or nucleus
- Eukaryotes have membrane-bound organelles and a nucleus.
Functions of Life: Necessary for an organism to be considered living; includes metabolism, growth, reproduction, response to stimuli, homeostasis, nutrition, excretion, and evolution.
Cell Size Determination: Divide the drawing size (in mm) by the magnification size (e.g., 10x or 100x).

1.2 - Ultrastructure of Cells

(Organelle functions are described, but specific details are omitted due to the extensive nature of the request. Descriptions of organelles are only brief)

Cytoplasm - Contains all the organelles in a cell
Ribosomes - Synthesize proteins
Nucleus (in eukaryotes) - Contains DNA, stores and controls the genes and thus all cell activity.
Rough Endoplasmic Reticulum - Modification and packaging of proteins
Smooth Endoplasmic Reticulum - Lipid synthesis
Golgi Apparatus - modifies sorts and packages proteins.
Lysosomes - Digest waste material
Mitochondria - Cellular respiration (ATP production)
Chloroplasts (in plant cells) - Photosynthesis.
Vacuoles - Storage and regulation of water pressure.
Vesicles - Transport
Microtubules- cytoskeleton supports, structure and cell division
Centrioles - Cell division in animal cells.
Cilia - Movement
Flagella - Movement

1.3 - Membrane Structure

Cholesterol: Maintains membrane fluidity and stability.
Proteins: Transport, signaling, and structural support.
Phospholipid Amphipathic Properties: Explains the bilayer structure of cell membranes due to hydrophobic (water-fearing) tails and hydrophilic (water-loving) heads.

1.4 - Membrane Transport

Solutions with differing concentrations and a semi-permeable membrane: The solution with more solute (the 10% sugar) will result in net water movement across the membrane to the other side until equilibrium is established
Daily Life Diffusion Example: Perfume spreading through a room.
Passive Transport: Movement of molecules from high to low concentration. Does not require energy
Active Transport: Movement of molecules against their concentration gradient and requires the use of energy.
Osmosis: Passive transport of water across a semi-permeable membrane.
Potato Experiment: The solution with a higher concentration of solute (solution B) resulted in a mass loss of the potato; therefore, solution B has more solute than solution A.
Hypotonic, Hypertonic, and Isotonic Solutions:
- Hypotonic: A solution with a lower solute concentration than another solution (water enters the cell).
- Hypertonic: A solution with a higher solute concentration than another solution (water leaves the cell).
- Isotonic: A solution with the same solute concentration as another solution (no net water movement).
Honeycrisp Apple Hypertonic Solution: The answer will vary depending on the concentration of the solution and the equilibrium point of the apple in the mixture. (The information is not detailed to allow precise calculation).

Molecular Biology

2.2 - Water

Adhesion: Water molecules stick to other surfaces.
Cohesion: Water molecules stick to each other.
Surface Tension: Water molecules stick together at the surface.
Specific Heat: Water absorbs a lot of heat without changing temperature significantly.
Water's Dipolarity: Explain how these properties relate to water's polarity.
Hydrogen Bonds: Due to the attraction between the positive hydrogen of one water molecule and the negative oxygen of another.
Hydrophilic/Hydrophobic: Hydrophobic substances are repelled by water, hydrophilic substances are attracted to water
Polar/Nonpolar: Polar molecules have unevenly distributed charges, nonpolar do not.

2.1 - Molecules to Metabolism

Carbon: It can form four covalent bonds, which allows for a vast array of complex molecules.
Monomer/Polymer: Monomers are single units, while polymers are made from linked monomers.
Macromolecule Monomers and Polymers:
- Carbohydrates (monosaccharides/polysaccharides)
- Lipids (fatty acids/triglycerides, phospholipids)
- Proteins (amino acids/polypeptides)
- Nucleic acids (nucleotides/DNA, RNA)

2.3 - Carbohydrates and Lipids

Carbohydrate Properties: Sugary, energy-rich molecules.
Lipid Properties: Fatty, nonpolar, hydrophobic molecules, energy storage.
Saturated/Unsaturated Fatty Acids: Saturated fatty acids have single bonds, are solid at room temp; unsaturated fatty acids have double bonds, liquid at room temp. Cis or trans isomers depend on the configuration of the double bonds (geometric arrangement). This relates to health by the types of fats consumed.
Condensation/Dehydration Synthesis: Combining monomers by removing water.
Hydrolysis: Breaking polymers by adding water.
Cellulose, Starch, Glycogen: Compare and contrast their structures and functions in energy storage and/or structural support.

2.4 - Proteins

Amino Acids, Polypeptides, and Proteins: Amino acids link together to form polypeptides, and polypeptides fold into proteins.
Protein Structure and Function: How protein structure relates to function will depend on the specific protein and not all are included: hemaglobin, insulin, collagen, actin, myosin, Rubisco, immunoglobulins, rhodopsin, spider silk.
Protein Structures: primary, secondary, tertiary, and quaternary structures.
Amino Acid Properties: How these properties determine the 3-D shape of proteins.
Denaturing Proteins: Altering the shape and thus function of proteins.

2.5 - Enzymes

Substrate/Product: Substrate is the molecule the enzyme acts on, the end product comes after the enzyme's work.
Enzyme Conditions: Enzymes function optimally within a specific range of pH, temperature and substrate concentration.
Active Site Changes: The active site undergoes changes in shape according to the alterations in function caused by changing conditions.
Enzyme Role: Enzymes speed up reactions, their activity is not consumed or used up.

Cellular Respiration and Photosynthesis

2.8 - Cell Respiration

Overall Equation: Glucose + Oxygen → Carbon dioxide + Water + ATP (energy).
ATP Function: Energy currency of cells; powers cellular processes.
Aerobic vs. Anaerobic Respiration:
- Aerobic requires oxygen, releases more ATP, produces carbon dioxide.
- Anaerobic does not require oxygen, releases less ATP, other products are listed but not exhaustive.

2.9 - Photosynthesis

Description: The process by which plants and some other organisms use sunlight to synthesize foods such as sugars, and release oxygen.
Overall Equation: Carbon dioxide + Water + Light Energy → Glucose + Oxygen
Tree Mass: Primarily from carbon dioxide, absorbed from the atmosphere during photosynthesis.
Visible Light Wavelengths and Photosynthesis: Photosynthesis primarily uses light in the blue and red portions of the visible light spectrum.

DNA and Protein Synthesis

2.6 - DNA & RNA

Nucleotide Components: Phosphate, sugar, and nitrogenous base.
DNA vs. RNA Venn Diagram: The Venn diagram should show similarities and differences between the two molecules.
Bonds in DNA: Covalent bonds link nucleotides, hydrogen bonds hold the two strands together.

2.7 - Replication, Transcription, Translation

Semi-conservative Replication: The new DNA molecule has one original strand and one new strand.
Replication, Transcription, and Translation:
- Replication copies DNA
- Transcription makes mRNA from DNA
- Translation uses mRNA to make proteins
mRNA, rRNA, and tRNA: mRNA carries genetic instructions, rRNA forms ribosomes, tRNA transfers amino acids to ribosomes.
Codons/Anticodons: Codons are three-base sequences on mRNA coding for an amino acid, anticodons are three-base sequences on tRNA, complementary to codons.
DNA Sequence Transcription and Translation (TAC CCC ACG): (The specific amino acid sequence translation will be dependent upon a codon chart and correct interpretation.

Note: Some questions require further details, specific calculations, examples or drawings. This summary provides a foundational overview.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers the essential concepts of the scientific method, the differences between theories and hypotheses, and the definitions of scientific errors and mistakes. Additionally, it explores statistical measures such as mean, mode, median, and standard deviation, providing a comprehensive overview of key scientific principles and data analysis methods.