Biogeochemical Cycles: Exam 1 Study Guide

• The study guide is designed to assist in reviewing the material covered in preparation for Exam 1, focusing on biogeochemical cycles.
• Not every detail will be covered, but should help in seeing some of the types of questions.
• Review notes, slides, and textbook sections to feel comfortable explaining these concepts/questions.

General Study Rules

• Quiz yourself first to assess your current knowledge before looking up answers.
• Treat your brain like a muscle; consistent effort strengthens it.
• Use short study periods of 30-45 minutes to allow the brain to transfer information from short-term to long-term memory.
• Avoid multitasking during study sessions to maintain focus.
• Collaborating with study partners and teaching the material can enhance understanding.
• Adequate rest is essential for both body and brain before an exam.

Science/Scientific Method

• The scientific method involves steps of observation, hypothesis, experimentation, analysis, and conclusion.
• Science is cyclical and iterative, with experiments building on previous work.
• Well-designed experiments should include a control group for comparison against a treatment group.
• A larger number of replications, like 100 instead of 10, increases the reliability and statistical power of an experiment.
• Scientific theories are well-substantiated explanations of some aspect of the natural world, while scientific laws are descriptive generalizations about how the natural world behaves under specific conditions.
• Objectivity means not being influenced by personal feelings or opinions in considering and representing facts.
• Parsimony refers to preferring the simplest explanation that accounts for the available evidence.
• Evaluate sources and their motivations to ensure that they are objective.

What is Life

• Consider what characteristics separate living beings from non-living things.
• Life is organized hierarchically, though it's not clear where organic molecules become life forms.
• An emergent property is a characteristic that appears as complexity increases.
• Plants harness energy from sunlight, while animals gather energy by consuming other organisms, after death the energy dissipates.
• Internal constancy, or homeostasis, is the maintenance of a stable internal environment.

Domains of Life

• The three domains of life are Bacteria, Archaea, and Eukarya.
• Each domain has distinct cellular characteristics.

Chemistry Basics

• Atoms are composed of subatomic particles: protons, neutrons, and electrons.
• Electrons orbit the nucleus and are crucial for chemical bonding.
• Chemical bonds include covalent, polar covalent, ionic, and hydrogen bonds.
• Electronegativity is related to how bonds form.
• Partial charges enable hydrogen bonds.
• Partial charges and hydrogen bonds contribute to unique characteristics of water.

Water Characteristics

• Hydrogen and oxygen atoms within a water molecule are held together by polar covalent bonds.
• Hydrogen bonds form between water molecules.
• Cohesion, due to surface tension, makes water very important to living things.
• Adhesion, including capillary action, enables water to adhere to surfaces.
• Water regulates temperature because it is slow to heat and cool because energy is required to break hydrogen bonds, therefore water can hold a lot of energy.

Solvents

• Water is a solvent because of its polarity, but not everything can dissolve in it.
• A solvent is a substance that dissolves another, while a solute is what gets dissolved, together they create a solution.
• Hydrophilic substances dissolve in water, while hydrophobic ones do not.
• Diffusion is driven by a concentration gradient, with molecules moving from areas of high to low concentration until equilibrium is reached.

pH

• pH measures acidity or alkalinity (basicity) and is crucial for cells, fish, humans, and plants.
• Proteins can be affected in structure and function by pH changes.

Why We Eat

• The body needs both energy and chemical building blocks (nutrients).
• Be able to summarize how what you eat is turned into your cells.

Molecules

• Organic molecules contain carbon.
• Dehydration synthesis builds larger molecules by removing water, while hydrolysis breaks them by adding water.
• Hydrophilic molecules dissolve in water; hydrophobic ones don't.
• Know the basics of the structure and functions of carbohydrates, proteins, nucleic acids, and lipids
• Know the monomers and polymers for the 3 major classes of organic molecules like carbohydrates, proteins and nucleic acids.

Molecules Usage

• Triglycerides and phospholipids contain major components, know where they can be found in a human diet.
• All of these molecules can be used for energy.
• R-groups in amino acids define their properties and influence protein structure in a 3D way.
• Proteins have four levels of organization.
• Exposure to extreme conditions can denature proteins, impairing their function.

Nutrient Cycles

• Water moves through living and non-living systems.
• Water's properties are very important to supporting life.
• Human activities impact water systems.
• Inorganic nutrients are taken in by plants and converted into organic macromolecules.
• Macromolecules can be broken into smaller components of carbohydrates, proteins, lipids, and nucleic acids by animals that eat plants.

Nitrogen, Carbon, and Phosphorus

• Nitrogen moves through ecosystems.
• Nitrogen's importance and function for organisms.
• In what form do plants take up nitrogen?
• How animals get nitrogen containing compounds?
• Humans use nitrogen for outside our bodies and how we impact the nitrogen cycle
• Phosphorus transfers through living components.
• What is phosphorus used for in organisms
• Carbon cycles between living organisms.
• How carbon is used or necessary for life
• Energy generation for macromolecules is through carbon building blocks.
• Decomposers recycle nutrients, making them accessible to plants and replenishing the food chain.
• Carbon cycles quickly, what happens with intermediate usage and long term storage in living systems
• Fossil sources of carbon and how humans make use of those carbon sources
• The importance of decomposers in recycling nutrients from living systems back into the soil so they can be taken up by plants and move through the food chain again
• How humans impact the carbon cycle.

Review material for Exam 1 with this study guide on biogeochemical cycles. Understand the scientific method, emphasizing observation, hypothesis, and experimentation. Learn effective study habits, including regular quizzes and focused study sessions.