Study of Life Chapter 1 Themes AP Bio

Pre Assessment Name the kingdoms of life. Name 3 types of cells. Contrast these cells. What are the 3 domains of all living things. Name 1 scientist whose research led to the development of the cell theory. What scientists led to the development of the DNA model? Name 5 characteristics that all living things posess. Who is the father of evolution? What is the purpose of a control group? What are protein catalysts?

OBJECTIVES 1. Briefly describe unifying themes that pervade the science of biology. 2. Diagram the hierarchy of structural levels in biology. 3. Explain how the properties of life emerge from complex organization. 4. Describe seven emergent properties associated with life. 5. Distinguish between holism and reductionism. 6. Explain how technological breakthroughs contributed to the formulation of the cell theory and our current knowledge of the cell. 7. Distinguish between prokaryotic and eukaryotic cells. 8. Explain, in their own words, what is meant by "form fits function." 9. List the five kingdoms of life and distinguish among them. 10. Briefly describe how Charles Darwin's ideas contributed to the conceptual framework of biology. 11. Outline the scientific method. 12. Distinguish between inductive and deductive reasoning. 13. Explain how science and technology are interdependent

Why study themes of Biology? Biology is an ever expanding body of knowledge too much to memorize it all need to generalize create a framework upon which to organize new knowledge themes are the key to understanding the nature of living organisms

Unifying Themes Emergent Properties~ hierarchy of life The Cell~ all organism’s basic structure Heritable Information~ DNA Structure & Function~ form and function Environmental Interaction~ organisms are open systems Regulation~ feedback mechanisms Unity & Diversity~ universal genetic code Evolution~ biology’s core theme; differential reproductive success Scientific Inquiry~ observation; testing; repeatability Science, Technology & Society~ functions of our world

Emergent Properties/Characteristics of Life Order. Organisms are highly organized, and other characteristics of life emerge from this complex organization. Cells. All living organisms are made of cells Reproduction. Organisms reproduce; life comes only from life (biogenesis). Growth and Development. Heredity

6. Energy Utilization. Organisms take in and transform energy to do work, including the maintenance of their ordered state. 7. Response to Environment. Organisms respond to stimuli from their environment. 8. Homeostasis. Organisms regulate their internal environment to maintain a steady-state, even in the face of a fluctuating external environment. 9. Evolutionary Adaptation. Life evolves in response to interactions between organisms and their environment.

I. Life’s Hierarchical Order The living world is a hierarchy, with each level of biological structure building on the level below it

I. Hierarchy of Organization Atoms Molecule Organelle Cells Tissues Organ Organism

Levels of organization beyond the individual organism: Populations Localized group of organisms belonging to the same species Community Populations of species living in the same area Ecosystems An energy-processing system ofi community interactions that include abiotic environmental factors Biosphere The sum of all the planet's ecosystems AP Bio

Form follows function The alignment of structure & function is seen at all levels of biology Levels of organization animation organ organism cell organelle

Check Point Diagram the hierarchy of structural levels in biology beginning with an Atom.

II. Cells are an organism’s basic units of structure and function Lowest level of structure capable of performing all activities of life. All organisms are composed of cells. unicellular or multi cellular The invention of the microscope led to the discovery of the cell and the formulation of the cell theory. Robert Hooke (1665) examination of cork- tiny boxes which he called "cells" (really cell walls). Antonie van Leeuwenhok (1600's) used the microscope to observe living organisms Matthias Schleiden and Theodor Schwann (1839) ~all living things are made of cells. This formed the basis for the cell theory.

Two major kinds of cells Prokaryotic cell = Cell lacking membrane-bound organelles and a membrane-enclosed nucleus. Archaebacteria and bacteria Generally much smaller than eukaryotic cells Contains DNA that is not separated from the rest of the cell, as there is no membrane-bound nucleus Most have tough external walls

Two major kinds of cells Eukaryotic cell = Cell with a membrane-enclosed nucleus and membrane-enclosed Organelles. Protists, plants, fungi, and animals DNA is segregated from the rest of the cell within the nucleus Some cells have a tough cell wall outside the plasma membrane (e.g., plant cells). Animal cells lack cell walls.

Check Point Explain how technological breakthroughs contributed to the formulation of the cell theory and our current knowledge of the cell.

Check Point Distinguish between prokaryotic and eukaryotic cells.

III. Reproduction Asexual Binary Fission~ bacteria Sexual Gametes Fruiting Bodies Flowers Meiosis

IV. Growth and Development Metamorphosis Puberty

You can make more, a lot like you! V. Heredity Heritable information in the form of DNA DNA – the genetic material – carries biological information from one generation to the next T R A I You can make more, a lot like you!

Heredity

Heredity DNA gene chromosomes Role of DNA

VI. Energy transfer Life is an open system need input of energy energy flows through energy comes in, energy goes out need a constant input need input of materials nutrients are recycled around & around nutrients ENTROPY RULES! DECOMPOSERS RULE, too!

Check Point What type of energy enters the atmosphere? What type of energy leaves the atmosphere?

You think they’re eating… They’re harvesting energy! Energy utilization You think they’re eating… They’re harvesting energy!

Organisms are open systems that interact continuously with their environments Organisms interact with their environment, which includes other organisms as well as abiotic factors. Both organism and environment are affected by the interaction between them. Ecosystem dynamics include two major processes: 1. Nutrient cycling 2. Energy flow

VII. Responsiveness Stimuli Response Nervous System Endocrine System Electrical Impulses

VIII. Homeostasis Organisms need to maintain a “steady state” in the face of changing conditions maintain homeostasis achieve this through feedback monitor the body like a thermostat turn on when it’s needed, off when its not

Feedback Positive feedback speeds a process up Negative feedback slows a process down Organisms and cells also use chemical mediators to help regulate processes

Feedback Regulation: Negative Accumulation of an end product of a process slows that process Example: sugar breakdown generates ATP; excess ATP inhibits an enzyme near the beginning of the pathway

Feedback Regulation: Positive An end product speeds up its production Example: blood clotting in response to injury

Examples of Regulation The hormone insulin, for example, signals cells in vertebrate organisms to take up glucose. As a result, blood glucose levels go down. In certain forms of diabetes mellitus, insulin is deficient and cells do not take up glucose as they should, and as a result, blood glucose levels remain high.

Provide an example of positive and negative feedback processes. Ex. Positive~ During pregnancy contractions increase until the baby is delivered.

Metabolism Sum of all chemical reactions in an organism Enzymes Activation energy Anabolism- builds Catabolism- breaks down

Metabolism

IX. Evolution Core theme of biology Charles Darwin

Evolution explains unity & diversity what do organisms have in common & why do similarities exist? common biochemistry & physiology evolutionary relationships connected through common ancestor Diversity but why are there differences? natural selection adaptations allow different individuals to survive in different environments

"Nothing in biology makes sense except in the light of evolution." Theodosius Dobzhansky: Integrating Genetics and Evolution Theodosius Dobzhansky, a Russian geneticist who moved to the United States, provided laboratory evidence for natural selection and variation where previously there had been only field observation. Dobzhansky's work with Drosophila, or fruit flies, provided new evidence that supported Darwin's theory that natural selection, acting on genetic variation in populations, is a driving force in evolution. -- Theodosius Dobzhansky March 1973 Geneticist, Columbia University (1900-1975) AP Bio

Examples Bacterial resistance to antibiotics Peppered Moths

Taxonomy

Taxonomy Need for a universal system Carolus Linnaeus Three Domains Bacteria Arachae Eukaryotes Kingdom-most inclusive Phylum Class Order Family Genus Species

3 Domains of Life- 6 Kingdoms Bacteria, Archaea, Eukarya Bacteria Archaea Eukarya

Organizing systems Making sense out of the diversity Hierarchical scheme Eastern gray squirrel Sciurus carolinensis

Scientific Name Binomial Nomenclature Scientific Name Genus species Examples Homo Sapien System is based on Phylogenetic relationships.

Science as a process of inquiry

Science as a process of inquiry Built on repeatable observations & testable, falsifiable hypotheses

Scientific Method Process which outlines a series of steps used to answer questions. Not a rigid procedure. Based on the conviction that natural phenomena have natural causes. Requires evidence to logically solve problems. The key ingredient of the scientific process is the hypothetico-deductive method Involves: 1. Asking a question and formulating a tentative answer or hypothesis by inductive reasoning. 2. Using deductive reasoning to make predictions from the hypothesis and then testing the validity of those predictions.

Inductive vs Deductive Reasoning Inductive reasoning = Making an inference from a set of specific observations to reach a general conclusion. Deductive reasoning = Making an inference from general premises to specific consequences Usually takes the form of If...then logic. Usually involves predicting experimental results that are expected if the hypothesis is true

Provide an example of Inductive & Deductive reasoning Ex. Deductive reasoning- If I step on the gas and turn the ignition, the car will start. Predicting results from a hypothesis Ex. Inductive-observations lead to generalizations

Holism vs Reductionism The principle that a higher level of order cannot be meaningfully explained by examining component parts in isolation. • An organism is a living whole greater than the sum of its parts. Ex- A cell dismantled to its chemical ingredients is no longer a cell. It is also difficult to analyze a complex process without taking it apart. Reductionism A complex system can be understood by studying its component parts. Ex- Watson and Crick deduced the role of DNA in inheritance by studying its molecular structure.

Provide an Example of Reductionism Ex. In order to understand inheritance, one must understand the molecular structure of DNA

Science, technology & society Science & technology must function within the rules of society Ethics

We have a love-hate relationship with technology. Pros Improved our standard of living. Cons Creation of new problems Ie. Increased population growth, acid rain, deforestation, global warming, nuclear accidents, ozone holes, toxic wastes, and endangered species.

Phylogeny Branching tree of life. Species that are very similar share a common ancestor at a recent branch point on the phylogenetic tree. • Less closely related organisms share a more ancient common ancestor.

Where all life began……. All life is connected and can be traced back to primeval prokaryotes that existed more than 3 billion years ago. In 1859, Charles Darwin published On the Origin of Species in which he made two major points: 1. Species change, and contemporary species arose from a succession of ancestors through a process of "descent with modification." 2. A mechanism of evolutionary change is natural selection.

Organisms don’t adapt; Organisms have adaptations. Natural selection Organisms don’t adapt; Organisms have adaptations.

Requirements for Natural Selection All species have the potential to overpopulate the earth. Many must die at an early age. Variation exists within the members of a species. Those with better adapted traits live longer and reproduce more often (differential reproduction) (Fecundity) Traits are inheritable. Process can account for new species and diversity.

Post Assessment Describe seven emergent properties associated with life. Distinguish between holism and reductionism. Explain how technological breakthroughs contributed to the formulation of the cell theory and our current knowledge of the cell. Explain, in their own words, what is meant by "form fits function.“ List the five kingdoms of life and distinguish among them. Briefly describe how Charles Darwin's ideas contributed to the conceptual framework of biology. Outline the scientific method. Distinguish between inductive and deductive reasoning.

ANY QUESTIONS? AP Bio