Biology Chapter 1: Introduction to Biology

Chapter 1: Introduction to Biology

• Biology is the scientific study of life, encompassing order, reproduction, growth/development, energy processing, regulation, response to the environment, and evolutionary adaptation.
• The cell is the fundamental structural and functional unit of life.
• Life is organized hierarchically: biosphere, ecosystem, community, population, organism, organ system, organ, tissue, cell, organelle, molecule.
• Emergent properties arise from interactions among component parts at each level of biological organization.
• Science uses an evidence-based process of inquiry to investigate the natural world, involving observations, hypotheses, predictions and tests (through experiments or further observation), and analysis of data.
• Scientific theories are broad in scope and supported by a large body of evidence.
• Hypotheses are tested using controlled experiments.
• Hypotheses can also be tested using observational data.
• Hypotheses about evolutionary relationships can be tested by comparing DNA sequences.
• Natural selection is a process resulting in adaptation by selectively reproducing changes in an organism's genotype.

Chapter 2: Chemical Concepts in Biology

• Organisms are composed of elements, with oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus comprising most of living matter.
• Atoms consist of protons, neutrons, and electrons.
• Radioactive isotopes are valuable in research and medicine.
• Atoms bond to form molecules via chemical bonds.
• Covalent bonds form by sharing electrons.
• Ionic bonds form through the attraction of oppositely charged ions.
• Hydrogen bonds are weak attractions between molecules.
• Chemical reactions involve the making and breaking of chemical bonds.
• Water has properties that are crucial for life: cohesion, high specific heat, high heat of vaporization, and density (ice floats).
• Water is the universal solvent.
• Cohesion helps water move in plants.
• Water moderates temperature.
• Aqueous solutions are important in biological systems.

Chapter 3: The Molecules of Life

• Life's molecular diversity is due to carbon's ability to form four covalent bonds.
• Hydrocarbons consist solely of carbon and hydrogen.
• Isomers have the same molecular formula but different structures.
• Chemical groups attached to carbon skeletons impart specific chemical properties.
• Cells make large molecules from small monomers.
• Carbohydrates are composed of carbon, hydrogen, and oxygen (CH2O) in a 1:2:1 ratio.
• Monosaccharides are simple sugars; disaccharides and polysaccharides are complex carbohydrates.
• Fats (triglycerides) are the main energy storage form in animals.
• Phospholipids are critical components of cell membranes.
• Steroids have diverse functions and include cholesterol.

Chapter 4: Cells: The Fundamental Units of Life

• Microscopes enable visualization of cells and their internal structures (ultrastructure).
• Cell size is vital for material exchange.
• Prokaryotic cells lack membrane-bound organelles.
• Eukaryotic cells are compartmentalized.
• The nucleus contains DNA.
• Ribosomes are the sites of protein synthesis.
• The endomembrane system includes components like the endoplasmic reticulum, Golgi apparatus, and lysosomes.
• Mitochondria are the organelles of cellular respiration.
• Chloroplasts carry out photosynthesis.
• Cell walls enclose and support plant cells.

Chapter 5: Membrane Structure and Function

• Membranes are fluid mosaics of lipids and proteins.
• Membranes form spontaneously.
• Passive transport is the movement of substances across membranes without energy input.
• Osmosis is the diffusion of water across a membrane.
• Active transport requires energy to move substances against their concentration gradient.
• Exocytosis and endocytosis are methods for transporting large molecules across the plasma membrane.
• Cells transform energy through chemical reactions.

Chapter 6: Cellular Respiration and Fermentation

• Photosynthesis uses solar energy to produce organic molecules.
• Cellular respiration breaks down organic molecules to release energy.
• Breathing provides oxygen for cellular respiration and removes carbon dioxide.
• Cellular respiration primarily occurs in mitochondria.
• Glycolysis, the citric acid cycle, and oxidative phosphorylation are three main stages of cellular respiration, producing ATP.

Explore the foundational concepts of biology in this chapter. Learn about the characteristics of life, hierarchical organization, and the scientific method as it applies to biological inquiry. Discover how emergent properties and evolutionary concepts relate to life forms on Earth.