BIOL 10103-001 - Exam 1 Study Guide

Identify, describe, and give examples of the 7 basic characteristics of life. Check the lecture for differences with the textbook.

Cellular organization → all living things are made of cells; Metabolism → chemical reactions that sustain life; Homeostasis → regulation of internal conditions; Growth and development → based on specific DNA instructions; Reproduction → sexual or asexual; Response to stimuli → react to environmental changes; Evolutionary adaptation → populations evolve over generations

List, describe, and give examples of levels of biological organization from atoms to the biosphere. (Small to Large)

Atom; Molecule; Organelle; Cell; Tissue; Organ; Organ system; Organism; Population; Community; Ecosystem; Biosphere

Describe the relationship between natural selection and adaptation

Natural Selection and Adaptation are directly connected as process and result. Natural Selection is the process by which individuals with heritable traits that improve survival or reproduction are more likely to survive and reproduce. Over time, these favorable traits become more common in a population. Adaptation is the result of Natural Selection. It is an inherited characteristic that increases an organism's ability to survive and reproduce in a specific environment.

Give examples of evolutionary adaptations.

Antibiotic resistance in bacteria is an evolutionary adaptation that allows resistant bacteria to survive antibiotics and reproduce; Thick fur and fat in polar bears help them survive cold environments; Camouflage in insects reduces the chance of being eaten by predators; Webbed feet in aquatic birds improve swimming ability; Long necks in giraffes allow access to higher food sources; Lactose tolerance in some humans allows adults to digest milk; Cactus spines reduce water loss and protect the plant in desert environments.

Distinguish between the three domains of life and the four kingdoms of Eukaryotes.

The three domains of life are Bacteria, Archaea, and Eukarya, which are classified based on cell type and genetic differences; Bacteria and Archaea are prokaryotic but differ in cell wall and membrane chemistry, while Eukarya includes organisms with a nucleus and membrane-bound organelles. Within the domain Eukarya, organisms are divided into four kingdoms: Protists, which are mostly unicellular; Fungi, which absorb nutrients and have chitin cell walls; Plants, which are multicellular, photosynthetic, and have cellulose cell walls; and Animals, which are multicellular heterotrophs that ingest food and lack cell walls.

Distinguish between science and technology.

Science is the systematic study of the natural world that seeks to understand how natural processes work through observation and experimentation, while technology is the application of scientific knowledge to develop tools, products, and solutions that solve practical problems.

Summarize some of the major challenges facing science.

Major challenges facing science include ethical issues surrounding new technologies such as genetic engineering and cloning, global problems like climate change and emerging diseases, the development of antibiotic resistance, limited natural resources, and the spread of misinformation and public misunderstanding of scientific findings.

List and describe the strengths of science.

The strengths of science include its reliance on evidence gathered through observation and experimentation, its testability and repeatability, its ability to self-correct when new data emerge, and its use of logical reasoning to build reliable explanations about the natural world.

Describe the difference between experimental and observational science.

Experimental science involves manipulating variables under controlled conditions to test cause-and-effect relationships, while observational science relies on observing and analyzing natural events without manipulating variables when experiments are not possible.

Distinguish between a law/principle and a theory as defined in the lecture and not the textbook.

A scientific law or principle describes what happens in nature and is often expressed mathematically, but it does not explain why the phenomenon occurs. A scientific theory explains how and why natural processes occur and is supported by extensive experimental and observational evidence.

Analyze a scientific experiment and identify the hypotheses, experimental groups, control groups, experimental/independent variables, response/dependent variables, and conclusions.

When analyzing a scientific experiment, the hypothesis is a testable explanation or prediction. The experimental group receives the treatment, while the control group does not. The independent variable is the factor that is manipulated, and the dependent variable is the factor that is measured. The conclusion states whether the results support or reject the hypothesis.

Formulate the predictive hypotheses, Null and Alternative, for an experiment.

A predictive hypothesis states that if one variable changes, then another will change as a result. The null hypothesis proposes that there is no difference or effect, while the alternative hypothesis states that a difference or effect does exist.

Determine whether inductive or deductive reasoning is being used. Identify examples of each.

Inductive reasoning involves making general conclusions based on specific observations, whereas deductive reasoning uses general principles to make specific predictions.

Describe each of the following as they have to do with experiments: model organism, confounding variables, replicates, objectivity, and data collection.

A model organism is a species commonly studied to understand biological processes. Confounding variables are uncontrolled factors that may affect experimental results. Replicates are repeated trials that improve reliability. Objectivity means minimizing bias, and data collection involves the systematic recording of observations and measurements.

Describe the peer review process.

The peer review process occurs when other scientists evaluate research for accuracy, validity, and quality before it is published.

Identify popular and peer-reviewed primary scientific literature.

Popular scientific literature is written for the general public and includes magazines and news articles, while peer-reviewed primary literature consists of original research articles written by scientists for scientists.

Describe the parts of a graph presenting scientific data.

A scientific graph includes a title, labeled x- and y-axes, appropriate scales, and a legend if multiple data sets are shown.

Logically draw conclusions from the scientific data presented on a graph.

Conclusions drawn from graphs are based on observable patterns, trends, and comparisons between groups.

Analyze an experiment, identifying strengths and weaknesses in the experimental design.

Strong experimental designs include proper controls, large sample sizes, and replicates, while weaknesses include bias, small sample sizes, and confounding variables.

Describe the atomic structure of atoms in terms of electrons, protons, and neutrons.

Atoms are composed of protons and neutrons in the nucleus and electrons in an electron cloud surrounding the nucleus.

Interpret the atomic structure of an atom using information from the periodic table, including atomic number, mass number, and atomic symbol.

The atomic number of an element represents the number of protons, the mass number is the total of protons and neutrons, and the atomic symbol is the element's abbreviation.

Distinguish between radioactive and stable isotopes.

Radioactive isotopes are unstable and emit radiation, whereas stable isotopes do not decay.

List uses for radioactive isotopes.

Radioactive isotopes are used in medical imaging, cancer treatment, and as tracers in biological research.

Define an ion

An ion is an atom that has gained or lost electrons, resulting in a positive or negative charge.

Describe how elements are combined into molecules.

Elements combine into molecules through chemical bonds formed by interactions between electrons.

Describe the different types of chemical bonds.

Elements combine into molecules through chemical bonds formed by interactions between electrons.

Describe how the characteristics of water relate to its chemical structure.

Water's polarity and hydrogen bonding explain its unique properties, including cohesion, adhesion, high heat capacity, and solvent ability.

Describe the characteristics of water and how they are important to life.

These properties make water essential for temperature regulation, chemical reactions, and transport of substances in living systems.

Describe the chemical nature of acid or basic solutions.

Acidic solutions release hydrogen ions and have a low pH, while basic solutions accept hydrogen ions and have a high pH.

Compare organic and inorganic molecules.

Organic molecules contain carbon and hydrogen, whereas inorganic molecules generally do not.

Describe the buildup and breakdown of polymers.

Polymers are built from monomers through dehydration synthesis and broken down through hydrolysis.

Recognize the basic chemical formula for a carbohydrate, as well as the chemical formula for glucose.

Carbohydrates generally have the chemical formula (CH₂O)n, and glucose specifically has the formula C₆H₁₂O₆.

Distinguish between monosaccharides, disaccharides, and polysaccharides.

Monosaccharides are single sugars, disaccharides are two sugars bonded together, and polysaccharides are long chains of sugars.

List the important polysaccharides to plants and animals, and where to find them.

Important polysaccharides include starch and cellulose in plants and glycogen in animals.

Describe the parts of lipid molecules.

Lipids consist of glycerol and fatty acids. Phospholipids form cell membranes, fats and oils store energy, and cholesterol stabilizes membranes. Unhealthy fats increase the risk of cardiovascular disease.

Compare and contrast the structure and functions of phospholipids, fats/oils, and cholesterol.

Proteins function as enzymes, structural components, transporters, and signaling molecules in cells.

Discern healthy fats from unhealthy ones and describe the effect of unhealthy fats on the body.

Polypeptides are formed when amino acids are linked together by peptide bonds.

Describe the functions of proteins in cells.

Protein structure includes primary (amino acid sequence), secondary (folding patterns), tertiary (overall shape), and quaternary (multiple polypeptide chains).

Explain how a polypeptide is constructed from amino acids.

A polypeptide is constructed when amino acids are linked together by peptide bonds. A peptide bond forms between the amino group of one amino acid and the carboxyl group of another through a dehydration synthesis reaction, releasing water. This process creates a long chain of amino acids called a polypeptide, which will later fold into a functional protein.

Describe and compare the 4 levels of protein structure.

Protein structure is organized into four levels. Primary structure is the linear sequence of amino acids in a polypeptide. Secondary structure forms when the chain folds into alpha helices or beta pleated sheets due to hydrogen bonding. Tertiary structure is the overall three-dimensional shape of a single polypeptide caused by interactions between side chains. Quaternary structure occurs when two or more polypeptide chains associate to form a functional protein.

Recognize the structure of a nucleotide.

A nucleotide is composed of three parts: a five-carbon sugar, a nitrogenous base, and one or more phosphate groups. Nucleotides are the building blocks of nucleic acids such as DNA and RNA, and they also form molecules like ATP.

Describe the function of ATP in cells.

ATP functions as the main energy currency of the cell. It stores energy in its phosphate bonds and releases energy when a phosphate group is removed, allowing cells to perform work such as muscle contraction, active transport, and chemical synthesis.

List the principles of the Cell Theory.

The Cell Theory states three main principles: all living organisms are composed of one or more cells, the cell is the basic unit of structure and function in living things, and all cells arise from preexisting cells.

Name the parts of the plasma membrane.

The plasma membrane is made of a phospholipid bilayer with embedded proteins, cholesterol, and carbohydrate chains. Phospholipids form the basic structure, proteins perform various functions, cholesterol helps maintain membrane fluidity, and carbohydrates are involved in cell recognition.

Describe the function of the plasma membrane.

The function of the plasma membrane is to act as a selectively permeable barrier that regulates what enters and leaves the cell. It helps maintain homeostasis, allows communication with other cells, and protects the internal environment of the cell.

Identify the key structures of the bacterial cell and their functions.

Key structures of a bacterial cell include the cell wall, which provides protection and shape; the plasma membrane, which controls movement of substances; the cytoplasm, where metabolic reactions occur; ribosomes, which synthesize proteins; nucleoid DNA, which contains genetic information; and sometimes flagella or pili, which aid in movement and attachment.

Explain the general differences between prokaryotic and eukaryotic cells.

Prokaryotic and eukaryotic cells differ mainly in complexity. Prokaryotic cells, such as bacteria, lack a nucleus and membrane-bound organelles, while eukaryotic cells have a nucleus and specialized organelles. Eukaryotic cells are generally larger and more complex than prokaryotic cells.

Recognize the structure and function of organelles of eukaryotic cells.

Eukaryotic cells contain specialized organelles that perform specific functions. The nucleus stores DNA and controls cell activities. Mitochondria produce ATP through cellular respiration. The endoplasmic reticulum has two forms: rough ER, which has ribosomes and synthesizes proteins, and smooth ER, which synthesizes lipids and detoxifies chemicals. The Golgi apparatus modifies, sorts, and ships proteins and lipids. Lysosomes contain digestive enzymes that break down waste and old organelles, and peroxisomes carry out oxidation reactions that detoxify harmful substances.

Identify cellular structures unique to plant and animal cells.

Some cellular structures are unique to certain types of eukaryotic cells. Plant cells contain a cell wall, chloroplasts, and a large central vacuole, which provide structure, enable photosynthesis, and store water. Animal cells contain centrioles, which are involved in cell division, and typically have smaller vacuoles.

Describe the structure and function of the cytoskeleton in cells.

The cytoskeleton is a network of protein fibers that extends throughout the cytoplasm. It provides structural support, maintains cell shape, allows movement of organelles, and plays a role in cell division.

Explain the roles of different cytoskeletal elements in cells.

The cytoskeleton is composed of three main elements. Microfilaments are thin fibers involved in cell movement and muscle contraction. Intermediate filaments provide mechanical strength and help cells resist tension. Microtubules are thick hollow tubes that maintain cell shape, transport materials, and form the spindle fibers during cell division.

Describe the origin of mitochondria and chloroplasts in the endosymbiotic theory of cells.

According to the endosymbiotic theory, mitochondria and chloroplasts originated from free-living prokaryotes that were engulfed by a larger ancestral cell. These prokaryotes formed a symbiotic relationship and eventually became permanent organelles, which explains why they have their own DNA and double membranes.

Describe the fluid-mosaic model of membrane structure.

The fluid-mosaic model describes the plasma membrane as a flexible phospholipid bilayer with embedded proteins that move laterally within the membrane. The lipids create a fluid background, while the proteins form a mosaic pattern.

Describe the 5 functions of membrane proteins.

Membrane proteins have five major functions. They transport substances across the membrane, act as enzymes, receive and transmit signals, allow cell-to-cell recognition, and anchor the membrane to the cytoskeleton or extracellular matrix.

Explain the relationship between membrane structure and selective permeability.

Selective permeability arises from the membrane's structure. The hydrophobic interior of the phospholipid bilayer allows small nonpolar molecules to pass easily while restricting large or charged molecules, which require transport proteins.

Predict the movement of molecules in different diffusion and osmosis scenarios.

In diffusion, molecules move from areas of higher concentration to lower concentration until equilibrium is reached. In osmosis, water moves across a membrane toward the area with a higher solute concentration. Water moves into a hypertonic solution, out of a hypotonic solution, and shows no net movement in an isotonic solution.

Describe the role of proteins in the movement of molecules across a membrane.

In diffusion, molecules move from areas of higher concentration to lower concentration until equilibrium is reached. In osmosis, water moves across a membrane toward the area with a higher solute concentration. Water moves into a hypertonic solution, out of a hypotonic solution, and shows no net movement in an isotonic solution.

Describe the different types of membrane transport, including whether, when, and how energy is used in each.

There are several types of membrane transport, which differ in whether energy is required. Diffusion is the passive movement of molecules from high to low concentration and does not require energy. Facilitated diffusion also moves substances down their concentration gradient but uses membrane proteins. Osmosis is the diffusion of water across a selectively permeable membrane and does not require energy. Active transport moves substances against their concentration gradient and requires energy, usually in the form of ATP. Vesicular transport, including endocytosis and exocytosis, requires energy to move large molecules or particles into or out of the cell.

Apply concepts from this chapter to the example of diabetes mellitus presented in the lecture.

In diabetes mellitus, cells have difficulty taking up glucose from the blood. In Type 1 diabetes, the pancreas does not produce enough insulin, while in Type 2 diabetes, cells do not respond properly to insulin. In both cases, glucose remains in the bloodstream instead of entering cells, leading to high blood sugar levels.

Describe how insulin is released into the blood.

Insulin is released into the bloodstream by the pancreas when blood glucose levels rise, such as after eating a meal. Specialized pancreatic cells detect the increase in glucose and secrete insulin to signal body cells to absorb glucose.

Describe the function of the GLUT protein.

The GLUT protein functions as a transport protein that allows glucose to enter cells by facilitated diffusion. It enables glucose to move down its concentration gradient across the plasma membrane.

Describe how the GLUT protein gets into the cell membrane.

GLUT proteins are inserted into the cell membrane in response to insulin signaling. Insulin triggers a signaling pathway that causes vesicles containing GLUT proteins to fuse with the plasma membrane.

Describe how insulin affects cells that take up glucose.

Insulin affects glucose uptake by increasing the number of GLUT proteins in the plasma membrane, which allows more glucose to enter the cell. This lowers blood glucose levels and provides cells with energy.

Describe the different forms of energy.

Energy exists in several forms, including kinetic energy, which is energy of motion, and potential energy, which is stored energy. Chemical energy is a form of potential energy stored in chemical bonds.

State the two laws of thermodynamics and describe how they apply to cells.

The first law of thermodynamics states that energy cannot be created or destroyed, only transformed, meaning cells convert energy from one form to another. The second law of thermodynamics states that every energy transfer increases entropy, meaning cells must continually input energy to maintain organization.

Discern which of the two different systems has greater entropy.

Between two systems, the system with greater disorder has higher entropy. Cells maintain low entropy by increasing entropy in their surroundings.

Identify how the terms anabolic, catabolic, endergonic, and exergonic relate to metabolic reactions.

Anabolic reactions build complex molecules and require energy, while catabolic reactions break down molecules and release energy. Endergonic reactions require an input of energy, whereas exergonic reactions release energy.

Summarize the ATP cycle and the role of ATP in the cell.

The ATP cycle transfers energy within the cell by converting ATP to ADP when energy is released and converting ADP back to ATP when energy is stored. ATP powers cellular work such as transport, movement, and chemical reactions.

Explain the purpose of metabolic pathways and how enzymes help to regulate them.

Metabolic pathways organize chemical reactions into efficient, step-by-step processes. Enzymes regulate these pathways by controlling the rate of each reaction and responding to cellular needs.

Explain how enzymes affect the energy of activation of a reaction.

Enzymes lower the activation energy of a reaction by stabilizing the transition state, allowing reactions to occur faster without being consumed.

Describe enzyme function.

Enzymes function as biological catalysts that bind specific substrates at an active site and convert them into products.

Describe the effect of environmental conditions on enzyme function.

Environmental conditions such as temperature, pH, and substrate concentration affect enzyme activity. Extreme conditions can denature enzymes by altering their shape.

Describe the function and importance of coenzymes and cofactors.

Cofactors and coenzymes assist enzymes in catalysis. Cofactors are inorganic ions, while coenzymes are organic molecules, often derived from vitamins, and both are essential for proper enzyme function.