BIO160 - Exam 1 Study Guide(1) - Tagged
Important Terms from Chapters 1 to 3
Chapter 1
Biology
Biology: The study of living organisms, encompassing their structure, function, growth, evolution, and interactions with the environment. It connects various domains of science, including genetics, ecology, and physiology.
Levels of Organization
Atom: The basic unit of matter, which combines to form molecules.
Molecule: Groups of atoms bonded together, forming the chemical building blocks of life.
Organelle: Specialized structures within a cell that perform distinct functions, such as mitochondria for energy production.
Cell: The basic unit of life, capable of performing all life processes, including growth and reproduction.
Tissue: A group of similar cells that work together to perform a common function, such as muscle tissue.
Organ: A structure consisting of various tissues working together to perform specific tasks, like the heart or lungs.
Organ System: Groups of organs that collaborate to perform complex functions; examples include the circulatory and respiratory systems.
Organism: An individual living entity capable of growth and reproduction.
Population: A group of individuals of the same species residing in a particular area, interbreeding and sharing genetic material.
Community: Different populations of various species interacting within a shared environment.
Ecosystem: The interaction between living organisms (the community) and their physical environment, including abiotic factors like soil and climate.
Biosphere: The global sum of all ecosystems; it represents all regions of Earth where life exists.
Emergent Properties: Unique characteristics that arise from the interaction of simpler components within a system, such as consciousness emerging from neural networks.
Homeostasis: The process through which living organisms maintain stable internal conditions despite external changes, critical for survival.
Characteristics of Life
Asexual Reproduction: A mode of reproduction where a single organism can reproduce independently, leading to offspring genetically identical to the parent.
Sexual Reproduction: Involves the combination of genetic material from two parents, increasing genetic diversity among offspring.
Taxonomy: The scientific classification of organisms into categories based on similarities and differences, aiding in the study of biodiversity.
Heterotroph: Organisms that cannot produce their own food and must consume other organisms for energy, like animals and fungi.
Autotroph: Organisms that can produce their own food through photosynthesis or chemosynthesis, such as plants and certain bacteria.
Prokaryote: Simple, unicellular organisms without a nucleus or membrane-bound organelles, like bacteria.
Eukaryote: More complex cells that contain a nucleus and organelles, including plant and animal cells.
Scientific Research Methods
Dependent Variable: The variable that is measured and observed in response to changes made in the experiment.
Independent Variable: The variable that is manipulated by researchers to assess its effect on the dependent variable.
Standardized Variable: Factors that are kept constant throughout the experiment to ensure that results are due to the independent variable alone.
Control Group: The baseline group in an experiment that does not receive the experimental treatment, allowing for a comparison to other groups.
Experimental Group: The group that receives the treatment or intervention as part of the experiment.
Placebo: An inactive substance or treatment designed to mimic the experience of the experimental group without any therapeutic effect.
Double-blinded: A research design where neither the participants nor the researchers know which individuals belong to the control or experimental groups, reducing bias.
Randomized: Participants are assigned to groups randomly to minimize selection bias and ensure that the groups are comparable.
Peer Review: A critical evaluation process by experts in the field prior to publication, ensuring the research meets the scientific standards.
Hypothesis: A testable statement predicting the outcome of an experiment, forming the basis for scientific inquiry.
Scientific Method: A systematic approach to research that involves making observations, forming a hypothesis, conducting experiments, and drawing conclusions.
Chapter 2
Structure of an Atom
Proton: A positively charged particle found in the nucleus of an atom, determining the element's identity and its atomic number.
Electron: A negatively charged particle orbiting the nucleus, influencing the atom's chemical behavior and bonding.
Neutron: A neutral particle also located in the nucleus, contributing to the atom's mass but not its charge.
Atomic Number: Equal to the number of protons in the nucleus, it determines the element type.
Mass Number: The total number of protons and neutrons in an atom's nucleus, indicating its mass.
Charge: The net electrical charge of an atom, determined by the balance of protons and electrons.
Isotopes: Variants of an element that have the same number of protons but a different number of neutrons, leading to different atomic masses.
Chemical Bonds
Nonpolar Covalent Bonds: Bonds formed when two atoms share electrons equally, resulting in no charge separation across the molecule.
Polar Covalent Bonds: Occurs when there is an unequal sharing of electrons, causing a partial positive charge on one end and a partial negative charge on the other.
Ionic Bonds: Formed through the transfer of electrons from one atom to another, generating oppositely charged ions that attract each other.
Hydrogen Bonds: Weak attractions between a hydrogen atom and electronegative atoms (like oxygen or nitrogen), important for biological structures like DNA.
Electronegativity: A measure of the tendency of an atom to attract a bonding pair of electrons, influencing molecular interactions.
Water and Its Properties
Cohesion: The phenomenon where water molecules stick to each other due to hydrogen bonding, important for water transport in plants.
Adhesion: The ability of water to adhere to other substances, crucial for processes like capillary action in plants.
pH Scale: Measures the acidity or basicity of a solution, ranging from 0 (acidic) to 14 (basic), with 7 being neutral.
Buffer: A substance that minimizes pH changes in biological systems by neutralizing excess acids or bases.
Biological Macromolecules
Monomer: A small, basic molecular unit that can join together to form larger molecules or polymers.
Polymer: Large molecules made up of repeating monomer units, essential for biological functions.
Hydrolysis: A reaction that breaks down polymers into their constituent monomers by the addition of water.
Dehydration Synthesis: The process of joining monomers to form polymers, during which water is released as a byproduct.
Carbohydrates: Organic molecules composed of carbon, hydrogen, and oxygen; they serve as energy sources and structural components (e.g., glucose as a monomer, starch as a polymer).
Proteins: Composed of amino acids; they play various roles such as enzymes, hormones, and structural components of cells.
Nucleic Acids: DNA and RNA, made up of nucleotides, responsible for storing and transmitting genetic information.
Lipids: A diverse group of nonpolar molecules, mainly involved in energy storage and forming cell membranes.
Triglycerides: Formed from glycerol and three fatty acids, serving as energy storage.
Phospholipids: Comprising a hydrophilic head and hydrophobic tail, crucial for forming cellular membranes.
Saturated vs. Unsaturated: Saturated fats contain no double bonds between carbon atoms, while unsaturated fats contain one or more double bonds, affecting their physical properties and health implications.
Chapter 3
Cell Theory
The foundation of biological sciences stating that:
All living organisms are composed of one or more cells.
Cells are the fundamental units of life.
All cells arise from pre-existing cells through cell division.
Microscopy
Light Microscope: Utilizes visible light to magnify specimens, suitable for observing living cells.
Transmission Electron Microscope (TEM): Utilizes electron beams to achieve high magnification, allowing the observation of internal cell structures.
Scanning Electron Microscope (SEM): Provides three-dimensional images of surfaces, allowing for detailed examination of cell structures.
Cell Size: Smaller cells have a higher surface area-to-volume ratio, which enhances efficiency in nutrient uptake and waste elimination.
Prokaryotes vs. Eukaryotes
Prokaryotes: Simple, single-celled organisms without a nucleus; they reproduce via binary fission and include bacteria and archaea.
Eukaryotes: More complex cells with a defined nucleus and membrane-bound organelles, comprising plants, animals, fungi, and protists.
Organelles and Their Functions
Nucleus: Acts as the control center of the cell, containing the cell's genetic material (DNA) and coordinating activities such as growth and reproduction.
Smooth Endoplasmic Reticulum (ER): Involved in lipid synthesis, detoxification, and calcium ion storage.
Rough Endoplasmic Reticulum (ER): Studded with ribosomes; it synthesizes proteins for export or for use in the cell membrane.
Lysosomes: Digestive organelles containing enzymes that break down waste materials and cellular debris.
Peroxisomes: Organelles that detoxify harmful substances and break down fatty acids through oxidation.
Vacuoles: Storage organelles that hold materials such as nutrients, waste products, or water in both plant and animal cells.
Golgi Apparatus: Modifies, sorts, and packages proteins and lipids for transport to their destinations.
Mitochondrion: The powerhouse of the cell, responsible for generating ATP through cellular respiration.
Chloroplast: Found in plant cells; the site of photosynthesis, converting solar energy into chemical energy in the form of glucose.
Membrane Composition
Plasma Membrane: A semipermeable phospholipid bilayer embedded with proteins that facilitate transport and communication across the cell.
Cytoskeleton
Microfilaments: Composed of actin, they provide structural support and are involved in cell movement and shape changes.
Intermediate Filaments: Provide mechanical support and help maintain the integrity and shape of cells.
Microtubules: Hollow tubes that support cell shape and are involved in intracellular transport and cell division.
Cell Junctions
Tight Junctions: Create barriers between cells to prevent leakage of fluids and maintain polarity.
Anchoring Junctions: Provide mechanical stability, connecting the cytoskeletons of adjacent cells and enabling them to withstand stress.
Gap Junctions: Allow for direct communication between adjacent cells through channels that permit the passage of ions and small molecules.
Plant Cell Structures
Cell Wall: A rigid outer layer that provides structure and protection, mainly composed of cellulose, and helps maintain turgor pressure in plant cells.
Plasmodesmata: Channels that connect plant cells, allowing for transport and communication of materials between cells.