Biology Mrs Schalles Chapter 1 The Science of

Biology Mrs. Schalles Chapter 1 The Science of Life Most notes & images in this show from HOLT Biology text unless noted otherwise. Image from: http: //www. le. ac. uk/bl/background 2. jpg

Most topics that will be covered in Biology are introduced in chapter 1 I. The World of Biology A. Branches of Biology B. 7 Characteristics of Living Things II. 3 Themes in Biology A. Unity of life’s: Genetic Code & Classification B. Interdependence: Environment & Ecology C. Evolution: Darwin, Natural Selection, Adaptations III. Scientific Method IV. Tools & Techniques: Microscopes & Other tools

Biology- the study of living things Biologists study life on many levels- from molecular to global. We are beginning to solve puzzles- how does a single cell grow into a multicellular plant or animal, how the human mind works, how solar energy is converted into chemical energy- food, how organisms network in biological communities like coral reefs, what threatens life

I. The World of Biology A. Definitions 1. Biology- the study of life “bio” means “life, “-logy” means the study of. 2. The branches of Biology -something in the vast field of biology interests you & is important to your life. -Biologists study the food supply, microorganisms, plants, health, ecology, biochemistry & more. We’ll look at some of the many fields of biology.

Branches of Biology • • • Anatomy- study of body parts Botany- study of plants Bacteriology- study of bacteria Cytology- study of cells Ecology – study of environment Embryology- study of development of individuals • Entomology- study of insects • Horticulture-study of growing • Immunology- study of immune system

• • Genetics – study of genes & heredity Hematology- study of blood Herpetology- study of snakes Microbiology – study of microorganisms Mycology- study of fungi Pathology- study of abnormal structures or functions Parasitology – study of parasites Paleontology- study of formerly-living organisms like fossils and dinosaurs • • Physiology-study of body part functions Taxonomy- study of classification Virology- study of viruses Zoology -The study of animals

3. Organism a living thing • Oldest fossil of a living organism- over 3. 5 billion years old • Earliest Life on Earth-For millions of years- only characteristics - unicellular, aquatic, microscopic, simple, anaerobic (cannot live in oxygen)

B. 7 Characteristics of Living Things 1. Organization/ Cell theory 2. Response to stimuli 3. Homeostasis 4. Metabolism 5. Growth & Development 6. Reproduction 7. Evolution

1. Organization/ Cell theory Cell Theory – theory that all living things - are made up of one or more cells, 1. Cells are the basic units of organisms 2. In a multicellular organism - cells specialized! 3. Cells come only from existing cells. -A cell is the smallest unit that can perform all life’s processes. Unicellular (single celled organism) Multicellular (many celled organism)

Prokaryotic & Eukaryotic cells

Organization -is the high degree of order within an organism’s internal & external parts & its interactions with the world. Hierarchy of organization of living things • Atom • Organic Molecule • Organelle • Cell • Tissue • Organism **See pages 6 -7 of your textbook

“Emergent Properties” • In the levels of the “hierarchy” there are new characteristics that are not apparent at a simpler level: • Atom-Molecule-Organelle-Cell-Tissue-Organism “A living organism is a whole greater than the sum of its parts. ” (cannot fully explain a higher level of order by breaking it down into its parts)

Cells are made of parts: • Atoms: Carbon (C), Nitrogen (N), Oxygen (O), Hydrogen (H), etc • Molecules -made of atoms: water- H 20, Sugars like Glucose (C 6 H 12 O 6), & large Proteins like Hemoglobin, C 738 H 1166 N 812 O 203 S 2 Fe (amino acids with a Fe ion) Phospholipids, DNA, etc • Organelles -made of molecules: Nucleus, Cell membrane, Chloroplast, Mitochondria, Ribosomes, etc.

Atom-Molecule-Organelle-Cell. Tissue-Organism health. yahoo. com www. scienceaid. co. uk www. answers. com www. mie. utoronto. ca www. search. com Health. yahoo. com web. jjay. cuny. edu http: //orchard. sbschools. net/library/links/body. jpg

7 Characteristics of Living Things 2. Response to Stimuli • Stimulus– a physical or chemical change in the internal or external environment. – that elicits or accelerates a physiological or psychological activity or response. ebiomedia. com • Response– Reaction to stimulus agent or action – For example: The owl dilates pupils in the eye to keep the level of light entering the constant. www. birds. cornell. edu

B. 7 Characteristics of Living Things 3. Homeostasis --The ability or tendency of an organism or cell to maintain stable internal conditions (equilibrium )by adjusting its physiological processes. -conditions such as: temperature, p. H, water content, uptake of nutrients by cells, etc. will be maintained in a constant rangeusually different than outside environment.

Homeostasis Questions: What would happen if: -an amoeba could not maintain a different internal amount of water than it’s surroundings? *It would explode with too much water *It would shrivel up without enough water -what if a desert mouse could not maintain a different internal temperature than the environment? * freeze to death in cold night air * bake in the daytime heat.

Quick Lab- page 8 Observing Homeostasis in Goldfish • • Read through the lab explanation. I will select the lab groups. Do not abuse the fish. dnr. cornell. edu Be very careful with the glass thermometers; be sure the temperature is the same as the labeled beaker. Do not kill the fish. Wipe up any spills. • Each person will hand-write a brief lab report (*see lab report format- no cover page or references needed) • Answer the 3 questions in the analysis section.

Quick Lab Results: • Gills are a respiratory structure that consists of many blood vessels surrounded by a membrane that allows for gas exchange. • It is protected by a hard plate called the operculum. • The gills will move faster at higher temperatures. • There is less dissolved oxygen in warmer water. • The fish is taking in more water & therefore more oxygen. • The rate at which the gills move affects the amount of oxygen- the amount of dissolved gas in the fish blood. This maintains homeostasis.

B. 7 Characteristics of Living Things 4. Metabolism – is the sum of all the chemical reactions that take in and transform energy and materials from the environment.

B. 7 Characteristics of Living Things 5. Growth and Development – Growth of living things results from the division & enlargement of cells. – Development is the process by which an organism becomes a mature adult.

B. 7 Characteristics of Living Things 6. Reproduction • life must have ability to reproduce, no organism lives forever. • Living organisms pass on hereditary information from parents to offspring.

2 Types of Reproduction 1. Asexual Reproduction-one parent divides into 2 identical offspring- EXAMPLES – Binary fission -bacteria – Budding -sponges -fungi like yeasts – Regeneration- earthworms Advantage- don’t need mate; Disadvantage- no genetic variations 2. Sexual Reproduction- 2 parents combine genetic info to form a unique individual -Egg of a female & sperm of a male form a ZYGOTE- info from both parents

Cell Reproduction: Mitosis & Meiosis There are 2 kinds of cell division in eukaryotic cells: • Mitosis occurs in cells for growth, development, repair or asexual reproduction. • Meiosis occurs during formation of gametes for sexual reproduction www. ccs. k 12. in. us/. . . /Humanembryology. htm

Reproduction An interesting organism: Volvox • Common colonial algae • Reproduces- asexually & sexually! • Asexual- 1 parent cell simply splits into 2 identical “daughter” cells • Sexual reproduction: The dark spheres are egg -cells. They are fertilized by small packages of sperm.

Reproduction & Inheritance Some important terms: • DNA molecule– deoxyribonucleic acid – has “how to” info • Gene- a segment on DNA macromolecule - may be 100 s of genes on a DNA strand - codes for a specific trait (like eye color) • Inheritance - traits passed from parent to offspring

B. 7 Characteristics of Living Things 7. Change over Time (Evolution) – Populations of living organisms evolve or change through time. -Evolution- from “evolve” meaning to change.

II. 3 Themes in Biology A. Unity of life’s Diversity -Life is diverse yet shares unity in molecules - DNA & genetic code B. Interdependence of Organisms -organisms interact with biotic & abiotic factors C. Evolution - theory that organisms change over time, the driving force is the environment.

DNA The Genetic code - all life has hereditary information in DNA –DNA molecules (Deoxyribonucleic acid) -Double helix - shape is formed by nitrogenous base pairs attached to a sugarphosphate backbone.

“Unity of Life’s Diversity” • Taxonomy: the classification of organisms • Tree of Life: shows that all living things have descended with modification from a single common ancestor

Phylogenic Tree • Shows relationships: • between 3 Domains & 6 Kingdoms

Taxonomic Classification: • 3 domains: Bacteria, Archaea, and Eukarya. • 6 Kingdoms: Archaea, Bacteria, Protista, Fungi, Plantae, and Animalia. • Further divided into smaller Taxonomic groups: – phyla – class – order – family – genus – species

3 Domains 1. Archaea -Prokaryotic cells (unicellular) -little understood, recently discovered life -probably oldest cells & found in extreme environments KINGDOM– Archaea 2. Bacteria = Prokaryotic cells (unicellular) -all the common bacteria, both good & bad -KINGDOM—Bacteria 3. Eukarya = Eukaryotic cells (have a nucleus) There are four kingdoms in Eukarya * Protista * Fungi * Plantae * Animalia

6 Kingdoms- examples Archaea, www. ucmp. berkeley. edu Fungi, Bacteria, www. dph. state. ct. us Plantae, Protista, www. microscopy-uk. org. uk Animalia. www. wetwebmedia. com danny. oz. au usmo 4. discoverlife. org usuarios. lycos. es

II. 3 Themes in Biology B. Interdependence • Ecology- How organisms interact with both other organisms & the environment. 1. Biotic Factors – living organisms 2. Abiotic Factors - non-living part of the environment (water, temperature, soil type, etc) 3. Ecosystems- Communities of different living species (Biotic factors)& interact with each other & their non-living environment (Abiotic factors).

Ecology • Is the study of how organisms interact with each other and their physical environment. • Environment – everything- biotic & abiotic- surrounding an organism

In ecology we will study: • • Trophic levels in the food chain The Biosphere Population growth, limiting factors Species interactions: Predation, competition, parasitism, Mutualism & Commensalism Successional changes in communities Major Biomes of the world Use of resources, pollution Watershed & Wetlands

Energy Relationships -study how organisms get, use & transfer energy • Sun- Source of almost all energy • Autotrophs- Organisms that make their own energy (food) (photosynthesis) • Heterotrophs – Organisms that obtain energy by eating other organisms

Food Chain & Food web in an Antarctic Ecosystem All food chains must start with a producer (autotroph)!!! What is the difference between a food chain & a food web?

Note numbers of organisms: Chart: many times more producers than large carnivores

BIOSPHERE • the thin layer of Earth’s crust, atmosphere & ocean layers that supports LIFE • includes: – All plant and animal life – Air, soil and water. – A variety of ecosystems that As far as we know so far - we are the only life in the universe…

Are we alone? Earth Age: About 4. 5 Billion Years Old Location: In the Solar System, on the outer edge of the Milky Way, about 28, 000 light years from the galactic center

Life in the Biosphere- 3 parts: • ATMOSPHERE – light blanket of air enveloping the earth, with more than half its mass within 4 miles of the surface and 98% within 16 miles • HYDROSPHERE --- the surface & subsurface waters in oceans, rivers, lakes, glaciers, groundwater • LITHOSPHERE --- upper earth's crust containing the soils that support plant life, the minerals that plants and animals require for life and the fossil fuels and ores that humans exploit.

Hydrosphere: • Surface Data: • 70% of earth is covered by water • Remaining 30% - 7 continental land masses. • Water Composition: • 97% salt water, • 3% fresh water – 2% glaciers/ice – only. 3% usable!

Atmosphere: • Air Composition: – 78% nitrogen, – 21% oxygen, – 1% other • Atmosphere Layers: – Trophosphere – Stratosphere – Mesosphere – Thermosphere – Exosphere

Lithosphere. Earth Layers: Inner core- solid Outer core- liquid Mantle- solid Asthenospheremolten like playdough Lithosphere- solid • Includes the crust, is very thin • Fragmented into tectonic plates which move. • Plate movement is called plate tectonics.

Ecology Levels of Organization • ORGANISM -Simplest Level (1 living thing) • POPULATION- All the members of the same species - that live in one place at a given time & make-up a breeding group. • COMMUNITY- Includes all the interacting populations in one area. • ECOSYSTEM- Includes all the living (biotic) & non-living (abiotic) factors in the environment. • BIOSPHERE- Thin layer of life around earth.

Levels of Organization

A Changing Environment • Abiotic Factors do not remain constant • Organisms able to survive a range of conditions, both natural cycles & manmade change • Most individuals can survive average conditions

Environmental Concerns -what are causes of pollution & where does it end up?

Watersheds • A watershed is the area of land where all of the water that is under it or drains off of it goes into the same place.

Watersheds come in all shapes and sizes. • They cross county, state, and national boundaries. No matter where you are, you're in a watershed! • In southwestern PA- our water drains first in to small creeks, then into the Monongahela river, then into the Ohio River & then the Mississippi River & ultimately the Gulf of Mexico.

Mississippi Watershed

Pollution that is added to water upstream will end up thousands of miles away. • • • Oil dripping from you car Salt & chemicals on the roadways Pesticides sprayed on your grass Cleaners washed down your sink drain Garbage dumped into the environment

Toxic discharge Scientists in Oregon & Washington States speculated that water discharged from a lake pumped almost dry by farmers has contributed to the toxic blue-green algae bloom that killed fish in this river. Dead blue gills, carp and frogs were readily visible in the water, which flows directly to the Tualatin River.

More fish die from a lack of oxygen than any other cause • Algae blooms -from pollution • Stagnant water – from building dams or other construction – cause growth of micro-organisms that use up all the oxygen & build up of undesirable chemicals, especially nutrients and heavy metals. • Also- Artificially warm water from industrial use • Remember: Warm water holds less oxygen than cool water

Pennsylvania Fishes • Note natural environments/ oxygen needs for local fish: • http: //sites. state. pa. us/PA_Exec/Fish_Boat/pafish/fishhtms/chapindx. htm

Municipal Solid Waste: An average person may produce a ton of refuse in a year • a volume that rapidly overflows local dumps.

A Modern Landfill

Problems with Landfills • Full- Many landfills are almost at capacity. • “NIMBY”- where do we put new landfills? ? ? • Leaks: –Leachate- a liquid that has formed as water leaks through compacted waste in a landfill. – Methane Gas -highly explosive, flammable gas formed as organic matter decomposes.

(3 rd Theme in Biology) C. Evolution 1. Theory that organisms change over time, the driving force is the environment. 2. Natural Selection- process by which adaptation is passed on to the next generation for best survival. 3. Adaptations-are favorable traits -Ex. - cactus plants adapted to desert

Science & Religionin answer to your questions: • Occasionally, the media may report on the “conflict” between religion & scienceimplying that one must “choose” – or that science has “replaced” religion. • For most there is no conflict! Many famous scientists were Christians who used their Judeo-Christian belief in a rational God as the foundation for their study. • Even Evolution is NOT contrary to personal faith.

Charles Darwin • English naturalist who presented compelling evidence that all species of life have evolved over time from common ancestors, through the process he called natural selection. http: //oreh. pef. uni-lj. si/~markor/Darwin/Charles_Darwin. jpg

Darwin’s trip around the world on the H. M. S. Beagle, especially the stops in South America & the Galapagos Islands were the basis for his work.

Darwin saw unusual things on his voyage & tried to explain them: • Strange Fossils • Large tortoises • Many kinds of beaks on finches http: //www. thisviewoflife. org/evolution/finch. jpg www. break-fresh-ground. com

Summary: 4 Main Parts of Darwin’s Reasoning • 1. Overproduction- more offspring are produced than can survive • 2. Genetic Variation- within a population, individuals have different traits • 3. Struggle to Survive- individuals must compete with each other to exist. • 4. Differential Reproduction- Organisms with the best adaptations to environment more likely to survive & reproduce.

Chapter 154 Main Parts of Darwin’s Reasoning Natural Selection

A simple example of Natural Selection - tiny fish may be able to hide under rocks and not get eaten by a predator - next generation has fewer large fish, “nature” has selected for smaller fish in that pond

Biology Terms: Extra Info that you will need to know Terms about Structure & Function • Morphology – the structure and form of an organism • Anatomy – the branch of morphology that deals with internal structure Structure is almost always related to function. Example- Bird beaksshape shows how it gets food

Science & Society • Applied Science- knowledge from biological science can be used to improve human life • Bioethics – The study of what is right or wrong as it applies to biological concerns. • Biotechnology- technology based on biology, especially when used in agriculture, food science, and medicine – genetic engineering, & DNA Technology- making new forms of life by transferring genes from one organism into another- like inserting gene for enzyme Chymosin -from the stomach of calves into the DNA of both bacteria and yeasts-

Biotechnology: Genetically engineered cheese –cheese is now cheaply made - with genetically modified yeast chymosin, (an enzyme which curdles milk, found in calves, who drink milk, but not in normal yeast!)

Genetic Medical Applications • Making medicine- until recently- medicine had to be collected from plants or made from chemicals. Now can make body substances like human blood clotting factors, insulin, vaccines & (HGH) Human. Growth. Hormone with GM bacteria. • Making body parts- may be able to clone cells & make new organs so that no rejection occurs. May be able to grow new human liver in another organism like a pig. • May also be able to screen for diseases, create “designer babies”, cure cancer.

Gene Therapy • Example: replace or repair faulty gene for cystic fibrosis. • Insert a copy of good gene from healthy person into virus. • Infect patient’s lungs with virus, virus delivers good gene. Now patient can make the right protein to stop accumulation of mucus & can breathe normally. Imagine being this mother of child with CF, Daily you must massage & loose mucus. Any cold could overwhelm & cause death. Now imagine what gene therapy represents.

Examples: Featherless chicken • a controversial featherless chicken which they say is faster growing. • will not need to be plucked, saving money in processing plants. • they would not be suitable for cooler countries, but OK in hot climates • There was a rumor that KFC uses these already but it is not true. http: //news. bbc. co. uk/1/hi/sci/tech/2000003. stm

Fishy Strawberries Flounder is a fish that can withstand icy cold temperatures. Scientists took the gene in the fish that Produces an antifreeze & inserted it into a plasmid of a bacterium The bacterium infected the strawberry & the flounder antifreeze gene entered the strawberry’s DNA The new GM strawberry cells are grown Into new plants that have strawberries which make a protein that keeps the fruit from frost damage. www. usbornequicklinks. com

GM foods- Golden Rice is part of the solution to world hunger & malnutrition. -Biofortified rice may alleviate life-threatening micronutrient deficiencies in developing countries-(decrease starvation) - Genetically modified- gene for provitamin A (β-carotene), is inserted into rice genome. www. goldenrice. org/

All living things have the same genetic building blocks DNA- deoxyribonucleic acid has 4 nitrogenous bases which make up the “alphabet” for the genetic code. SO- the same sequence of DNA (gene) codes for an enzyme, a protein or other molecule no matter which organism that gene is in. That is the basis for Gene technology

Biotechnology • There is currently much debate among scientists, politicians & environmentalist about the safety & quality of genetically modified products, especially foods. • It is very likely that you have already eaten multiple products that were produced with biotechnology and/or DNA technology

III. The Study of Biology A. The Scientific Method Steps: 1. Observation 2. Hypothesis 3. Prediction 4. Experiment 5. Data Analysis/ Conclusions 6. Communication/ Verification B. Evaluating Bias- at times, scientists have conflicts of interest. A scientist’s goal should be finding facts, not support of government agency agenda or the desired results of a pharmaceutical company.

Remember: Experiment terms – Control group provides a normal standard against which we compare results of the experimental group. – Experimental group is identical to the control group except for one factor. – Variables: factors that change – Theory -a set of related hypotheses confirmed to be true many times – An advantage of the scientific method is that it is unbiased & repeatable.

IV. Tools & Techniques A. Microscopes 1. Types of Microscopes *Compound light microscope -shines light through a specimen (must have thin slice of object) -uses 2 lens to magnify image. *Electron microscope -SEM (scanning electron microscope) -TEM (transmission electron microscope) 2. The parts of the Microscope- see hand out

Compound microscopes Used to magnify thin slices of specimens www. slic 2. wsu. edu

Magnification with each lens • TOTAL MAGNIFICATION= low power magnification X eye piece magnification • The eyepiece is 10 X • Low power is 4 X • Other lens may vary- usually - 10 X - 40 X

Microscope Use: • • Carry the microscope with 2 hands. By the “arm” & one hand under the base Look through eyepiece & keep both eyes open Place the slide that you want to view over the aperture and gently move the stage clips over top of the slide to hold it into place. • ALWAYS begin use & focus with the *Microscope on LOW Power (4 X) !!!! *Make sure the stage is all the way down. !!!!! • Always Begin focusing with the coarse adjustment

Light Microscopes – The eyepiece magnifies the image. – The objective lens enlarges the specimen. – The stage is a platform that supports slides with specimens. – The light source is a light bulb that provides light for viewing images.

Magnification & Resolution – Magnification is the increase of an object’s apparent size. – Resolution is the power to show details clearly in an image.

Figure 1. Relative Size of Microbes. E. M. refers to the Electron Microscope. www. slic 2. wsu. edu

Object Size and Magnifying Power of Microscopes

B. Other tools • Centrifuge-spinning separation of materials in a liquid that have different densities • Autoclave – heating chamber to disinfect • Chromatography -is any technique that separates different substances based on their chemical or physical properties • Electrophoresis - is a technique for separating particles that have an electrical charge. • Spectrophotometer -determines what a substance is by measuring the amount of each wavelength of light absorbed by the sample. • Computers are one of the most important tools used in biology studies. http: //www. chs. k 12. nf. ca/science/b 2201/Web. CT-Copy/units/unit 1 -02. htm

Electron Microscopes – Scanning electron microscopes pass a beam of electrons over the specimen’s surface for better viewing the external surface of a specimen. – Transmission electron microscopes transmit a beam of electrons through a thinly sliced specimen for better viewing the internal structures of a specimen.

C. Units of Measure • SI Units – Scientists use a single, standard system of measurement, called the metric system. The official name of the metric system is Système International d’Unités or SI.

Questions Which of the following is the hereditary material in most living things? F. DNA G. lipids H. oxygen J. carbon dioxide

Questions. Which of the following does evolution help explain? A. how organisms reproduce B. how organisms grow and develop C. how organisms are related to each other D. how organisms obtain and metabolize energy

Questions Which of the following does the hierarchy of organization within an organism describe? A. metabolism B. homeostasis C. internal structures D. relationship to the physical environment

Questions To which of the following does the resolution of a microscope refer? F. its ability to show detail clearly G. its power to scan the surface of an object H. its series of interchangeable objective lenses J. its power to increase an object’s apparent size