Evolution and the Foundations of Biology Introduction: Evolution and the Foundations of Biology
Introduction: Evolution- change over time. How an organism adapts to its environment Posing questions about the world and seeking answers through inquiry are central to biology.
Concept 1.1 Studying the diverse forms of life reveals common themes New properties emerge at successive levels of biological organization. From Microscopic organisms to biospheres we have classifications and hierarchy to organize living organisms. Put the following terms in order from least to greatest: Organisms biosphere communities organelles Molecules tissues cells populations Ecosystems organs organ systems
Concept 1.1 cont… Reductionism- the process of reducing complex systems into simpler components that are more manageable to study. Organism-DNA Emergent Porperties- properties that arrise from one level to the next. DNA codon protein trait Arrangement and interactions of the simpler structures cause increasing complexity
Concept 1.1 Systems biology- exploration of a biological system by analyzing the interactions among its parts. Example- how does a drug that lowers blood pressure affect the functioning organs throughout the body. Think about side effects. Sturcture and Function: By analyzing structure of a biological system it gives you an idea about the function of the structure. Cell- an organisms basic unit of structure and function. Smallest unit of organization that can preform all required activities.
THEME: Life’s processes involve the expression and transmission of genetic information. Within cells structures called chromosomes contain genetic information n in the form of DNA. Chromosomes are visible during division. Each time the cell divides it first replicates DNA so each of 2 offspring inherit a complete set identical to the parents DNA Each chromosome contains 1 very long struand of the DNA with hundreds or thousands of GENES (the unit of inheritance) We each began as one cell and now contain trillions of differentiated cells. (WHAT IS CELL DIFFERENTIATION?)
Chromosome Structure
HOW DOES DNA STORE INFORMATION? Double Helix with 4 base pairs ___ ___ ___ and ___ Encodes similarly to our alphabet.
DNA DNA is the blueprint for proteins, which are the driving force in carrying out its activities. Made up of nucleotides. Genes control protein production indirectly using a related molecule called RNA as an intermediary DNARNA Protein = gene expression Not all RNA molecules in the cell are translated into proteins. Some RNA’s carry out other important tasks such as regulation of protein coding genes.
Genes A particular sequence of nucleotides says the same thing in one organism as it does in another. Differences between organisms reflect differences between their nucleotide sequences rather than between their genetic codes. GENOMICS: Large scale analysis of DNA sequences Entire library of genetic instructions that an organism inherits is called its genome. Typical human has 2 similar sets of chromosomes with roughly 3 billion nucleotide pairs
Genetic Revolution Since the early 90’s genetic research has exploded Human Genome Known as well as many other organisms Bacteria, fungi, animals BIOINFORMATICS: Use of computational tools to store organize and analyze huge volumes of data BLAST database
Theme: Life Requires the Transfer and Transformation of Energy and Matter All life requires energy Ultimately where does all energy come from? Trophic Levels and Chlorophyll
THEME: Organisms Interact with other Organisms and the Physical Environment Each organism interacts continuously with the physical factors in its environment. How does a tree interact with its environment? MAKE A CHOICE CHAMBER
CONCEPT 1.2 Evolution accounts for the unity and diversity of life Diversity is the hallmark of life We have currently identified 1.8 million species but biologists estimate 10-100 million out there. Classifying diversity 3 DOMAINS of Life BACTERIA ARCHAEA EUKARYA Although diverse it displays a remarkable amount of unity .. With universal DNA languages and other similarities
Charles Darwin and Evolution Origin of the Species 1. species have arisen from a succession of ancestors that differed from them. 2. Natural selection is a mechanism for descent with modification Darwin had 6 points leading to his theory Adaptation competition Variation natural selection Overproduction speciation
Concept 1.3 BIOLOGICAL INQUIRY entails forming and testing hypotheses based on observations of nature. Science – “to know” INQUIRY- Search for information and explanations of natural phenomena Elements of inquiry include: Challenge careful planning adventure Luck creativity persistence Reasoning patience RESEARCH Science is not as structured as people think. This year you will be bold and adventurous and explore the world around you!
Process of inquiry: Making observations Forming logical hypotheses Recording data both quantitative and qualitative Forming logical hypotheses Testing Reforming hypotheses Collective and analyzing observations can lead to important conclusions based on a type of logic called INDUCTIVE REASONING We derive generalizations from a large # of specific observations
Forming and Testing Hypotheses A HYPOTHESIS is a tentative answer to a well framed question, it is an explanations on trial. Rational accounting for a set of observations based on available data and guided by inductive reasoning leading to TESTABLE predications by further observations and experiments. Flashlight fails Question? Hypothesis?
Inquiry Deductive Reasoning: Inductive takes large sets of information and comes up with a reason Deductive takes a small scale example and applies it to a large scale If…then.. Pg13
Experimental Controls Controlled experiments are designed to demonstrate the effect of one variable by testing control groups and experimental groups that differ in only that variable. Scientific theory broad scope, generaltes new hypotheses and is supported by a large body of evidence. Technology method or device that applies scientific knowledge for a purpose that effects society
Parts of an Experiment Control- standard used for comparison, no variables used Constant- Things that do not change in the experiment. Independent variable- What is being tested or changed in the experiment Dependent variable- the outcome being measure. (What was I looking for? Growth ?) JUSTIFICATION JUSTIFICATION JUSTIFICATION