Biology Exam 1 Flashcards

Hypothesis and Testing Concepts

• Hypothesis: Testable and falsifiable explanation for a specific question; cannot be proven absolutely true.
• Null Hypothesis: Proposes no relationship exists between two variables.
• Control Group: Serves as a baseline for comparison; remains unmanipulated.
• Treatment Group: Group that receives the manipulated condition for comparison.

Variables in Research

• Independent Variable: Condition that researchers change to observe its effects.
• Dependent Variable: The outcome that is measured to determine the effects of the independent variable.
• Sample Size: Larger sample sizes provide more reliable and generalizable results.

Psychological and Statistical Concepts

• Placebo Effect: Phenomenon where individuals experience positive outcomes from a treatment due to their expectations, emphasizing the need for control groups.
• Statistics: Numerical data summary that identifies patterns and allows generalizations from sample to population.

Common Misunderstandings

• Pseudoscience: Claims made without rigorous scientific support; often sounds scientific but lacks methodical studies.
• Anecdotal Observations: Conclusions drawn from limited personal experiences rather than systematic evidence.

Scientific Theory and Biological Concepts

• Theory: Highly substantiated explanation for natural phenomena, built from hypotheses supported by extensive evidence.
• Biological Molecules: Molecules produced by living organisms, which include organic molecules.

Molecules and Chemical Bonds

• Organic Molecules: Contain carbon; categories include carbohydrates, lipids, proteins, and nucleic acids.
• Ionic Bond: Occurs through the attraction of oppositely charged ions.
• Covalent Bond: Involves the sharing of electrons between atoms; stronger than ionic bonds.
• Hydrogen Bond: Weak bond formed between polar molecules, affecting properties like water density.

Properties of Water

• Cohesion: Water molecules attract each other, forming droplets.
• Large Heat Capacity: Water can absorb substantial heat without significant temperature changes.
• Low Density as a Solid: Ice floats on water due to its molecular structure.
• Good Solvent: Water effectively dissolves a variety of substances, enhancing biological processes.

Macromolecules and Carbohydrates

• Macromolecules: Large molecules like carbohydrates, lipids, proteins, and nucleic acids composed of smaller subunits.
• Carbohydrates: Main energy source for cells, also serve structural roles.
• Monosaccharides: Simple sugars acting as the basic units of carbohydrates, containing 3-7 carbon atoms.
• Polysaccharides: Complex carbohydrates like starch; consist of long chains of monosaccharide units.
• Cellulose: Provides dietary fiber that aids digestion and reduces disease risk.

Health and Dietary Concepts

• Diabetes: Condition marked by impaired insulin response or production.
• High Fructose Corn Syrup: Common sweetener in beverages; rapidly increases blood sugar and is metabolized differently than carbohydrates.

Statistical Probability

• The probability of a coin toss resulting in heads after eight consecutive tails remains 1/2, demonstrating Independence of events.

Scientific Method

• Steps include articulating a problem, analyzing data, formulating a hypothesis, and sharing results with the scientific community.