Nature of Science and Cell Biology

Study Notes

Nature of Science

The scientific method follows a process of observation, hypothesis formation, experimentation, data collection, and conclusion.
A theory is a well-supported explanation, distinguishing it from a testable prediction, or hypothesis.
Errors in experiments are systematic inaccuracies; mistakes are unintended actions.
Mean represents the average; mode is the most frequent value; median is the middle value.
Standard deviation quantifies data variability, depicted visually by error bars on graphs.

Cell Biology

Cells are small to maximize surface area-to-volume ratios for efficient exchange.
Prokaryotic cells lack a nucleus, while eukaryotic cells have membrane-bound organelles.
Key life functions include metabolism, growth, reproduction, response, and homeostasis.
Major organelles include the nucleus (DNA storage), ribosomes (protein synthesis), mitochondria (energy production), and Golgi apparatus (protein modification).
Cholesterol stabilizes cell membranes; amphipathic phospholipids form bilayers.
Osmosis involves water movement from lower to higher solute concentration; potatoes in hypotonic solutions gain mass; those in hypertonic solutions lose mass.
Passive transport (diffusion, osmosis) requires no energy; active transport (Na+/K+ pump) requires energy.
Hypertonic solution: higher solute concentration; hypotonic solution: lower solute concentration; isotonic solution: equal solute concentration

Molecular Biology

Water's dipolarity facilitates cohesion, adhesion, and surface tension.
Carbon's versatility enables the formation of diverse macromolecules.
Four main macromolecules are proteins, carbohydrates, lipids, and nucleic acids, built from specific monomers forming polymers.
Anabolism builds molecules (e.g. photosynthesis); catabolism breaks molecules down (e.g., respiration).
Saturated fats are solid at room temperature; unsaturated fats are generally healthier.
Proteins denature under extreme conditions, losing their shape and function.
Enzymes act on substrates to form products, being reusable.

Cellular Respiration and Photosynthesis

Cellular respiration equation: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + ATP.
Aerobic respiration yields more ATP than anaerobic respiration.
Photosynthesis equation: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂.
Light wavelength influences photosynthesis; red and blue light are most effective.

DNA and RNA

DNA uses deoxyribose, while RNA uses ribose.
DNA is double-stranded, RNA is single-stranded; both are nucleic acids.
Covalent bonds form the sugar-phosphate backbone; hydrogen bonds link base pairs.
Replication (DNA → DNA), transcription (DNA → RNA), and translation (RNA → protein) occur in the nucleus and cytoplasm.
Codons (mRNA triplets) pair with anticodons (tRNA) to form proteins.

Genetic Code

The codon chart matches RNA codons to amino acids.
AUG is the start codon (methionine); UAA, UAG, and UGA are stop codons.
Example: DNA sequence TAC CCC ACG → mRNA AUG GGG UGC → Amino acids: Met-Gly-Cys.

Digestive System

Major organs include the mouth (mechanical digestion), esophagus (food transport), stomach (protein digestion), and intestines (nutrient absorption).
Accessory organs are the liver (bile production) and pancreas (enzyme secretion).

Description

This quiz covers essential concepts in the nature of science and cell biology. You'll explore the scientific method, types of cells, key organelles, and important statistical measures. Test your knowledge on how these fundamental ideas interconnect within the realm of biological sciences.