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Biology
Biology is the study of all living things.
Lemur at Animal Kingdom
Kingdom:Animalia
Phylum: Chordata
Class:Mammalia
Order:Primates
Suborder:Strepsirrhini
Infraorder: Lemuriformes
Watch Promo Clip of "Planet Earth"
First... The Basics
Writing in Science
Because society relies heavily on written expression and printed material, it is important for you to posses effective writing skills. You will be expected to:
Keep good records of all investigations and activities
Record notes from text material and lectures/discussions
Submit complete lab reports (format provided by me) following the scientific method
Scientific Method
The Cell
Plant cells have cell walls, chloroplasts (for photosynthesis) and lack of centrioles.
Animal cells have cell membranes rather than a cell wall and have no chloroplasts.
Cell Theory
1. All organisms are composed of one or more cells, and the life processes of metabolism and heredity occur within these cells.2. Cells are the smallest living things, the basic units of organization of all organisms.
3. Cells arise only by division of a previously existing cell.
Photosynthesis and Respiration
Photosynthesis: Calvin Cycle
Respiration
Where In cholorophyll-bearing cells
When: In the presence of light
Input: Carbon dioxide and water
Output: Reduced carbon compounds, oxygen, and water
Energy sources: Light
Energy result: Energy stored
Chemical reaction: Reduction of carbon compounds
Energy carrier: NADPWhere: In all cells
When: All the time
Input: Reduced carbon compounds and oxygen
Output: Carbon dioxide and water
Energy Sources: Chemical bonds
Energy Result: Energy released
Chemical reaction: Oxidation of carbon compounds
Energy Carriers: NAD and FAD
NAD, FAD and ATP are all involved in the Krebs Cycle- a process for energy and metabolism.
NAD is an electron carrier, FAD is an electron acceptor, and ATP is the energy currency of the cell.
Protein Synthesis
DNA encodes for the production of amino acids and proteins
This process can be divided into two parts:
Transcription
Before the synthesis of a protein begins, the corresponding RNA molecule is produced by RNA transcription. One strand of the DNA double helix is used as a template by the RNA polymerase to synthesize a messenger RNA (mRNA). This mRNA migrates from the nucleus to the cytoplasm. During this step, mRNA goes through different types of maturation including one called splicing when the non-coding sequences are eliminated. The coding mRNA sequence can be described as a unit of three nucleotides called a codon.Translation
The ribosome binds to the mRNA at the start codon (AUG) that is recognized only by the initiator tRNA. The ribosome proceeds to the elongation phase of protein synthesis. During this stage, complexes, composed of an amino acid linked to tRNA, sequentially bind to the appropriate codon in mRNA by forming complementary base pairs with the tRNA anticodon. The ribosome moves from codon to codon along the mRNA. Amino acids are added one by one, translated into polypeptidic sequences dictated by DNA and represented by mRNA. At the end, a release factor binds to the stop codon, terminating translation and releasing the complete polypeptide from the ribosome.
The invention of the microscope has allowed us to investigate a whole new world of tiny objects.
Microscopes magnify and resolve, which tend to be mistaken as the same but are two very different things.
Magnification \mag-ne-fe-'ka-shen\ n 1. apparent enlargement of an object 2. the ratio of image size to actual size
A magnification of "100x" means that the image is 100 times bigger than the actual object.Resolution \rez-e-loo-shen\ n 1. clarity, sharpness 2. the ability of a microscope to show two very close points separately
resolution example below
Scientific Photography through the Microscope
Prepared Specimen Slides
Recording Field of View
Mitosis
In Meiosis I, chromosomes in a diploid cell re-segregate, producing four haploid daughter cells. It is this step in Meiosis that generates genetic diversity.
Meiosis II is similar to mitosis. However, there is no "S" phase. The chromatids of each chromosome are no longer identical because of recombination. Meiosis II separates the chromatids producing two daughter cells each with 23 chromosomes (haploid), and each chromosome has only one chromatid.
Major differences between mitosis and meiosis
1. Number of cell divisions and products.
mitosis - one cell division resulting in two daughter cells meiosis - two cell divisions resulting in four products of meiosis
2. Ploidy (# chromosome sets) per nucleus.
mitosis - 2N to 2N meiosis - 2N to N to N 3. Synapsis of homologous chromosomes.
mitosis - no pairing meiosis - pairing at zygotene of prophase I 4. Exchange of genetic material between synapsed homologous chromosomes.
mitosis - does not occur meiosis - occurs at pachytene of prophase I (first visible at diplotene) 5. Timing of division of centromeres.
mitosis - occurs at anaphase meiosis - occurs at anaphase II but not at anaphase I 6. Genetic variation.
mitosis - conservative process; does not lead to genetic variation meiosis - leads to increased genetic variation following recombination (crossing-over)
Jean-Baptiste Lamarck
1774-1829
French Botanist
Among the first scientists to recognize
living things have changed over time all species were descended from other species He also recognized organisms were somehow adapted to their environments
Charles Darwin
Father of Evolutionary Biology
1809 - 1882
British Naturalist
On The Origin of Species
Proposed a mechanism for evolution
Natural Selection
Presented evidence demonstrating that the process of evolution has been taking place for millions of years
Continues in all living things
Gregor Mendel
Father of Genetics
1822 - 1884
Mendelian Genetics
Postulates:
Unit Factors ( genes) come in pairs
Dominance vs. recessiveness
Segregation of alleles into gametes of equal frequency
Independent assortment of alleles from different gene pairs into gametes
Mendel did his research on the garden pea because it was easy to breed, quick turn around, and it was easy to see the changes in generations. Mendel's work went unnoticed for many years until 3 scientists came across his work in the early 1900's. At that time Mendel was given the name "Father of Genetics" for his major contribution to the field of genetics.
See Genetics Page
Corn Snake
Pantherophis guttatus
(formally known as: Elaphe guttata)
Fruit Fly
Drosophila melanogaster
Circular Plasmid
Linear Plasmid
Artificially Acquired Immunity
Active Immunity Passive Immunity Antigens (weakened, dead, or fragments of microbes) are introduced in vaccines. Preformed antibodies in an immune serum are introduced into the body by injection (e.g. antivenom used to treat snake bites). The body produces antibodies and specialized lymphocytes. The body does not produce any antibodies.
Drug Research & Development
AstraZeneca Aventis Pasteur Novartis Boehringer Ingelheim Pfizer GlaxoSmithKline Proctor & Gamble Merck Roche
The Miller-Urey Experiment
Miller-Urey experiment states: molecules that are the building blocks of living organisms form spontaneously under conditions designed to simulate those of the primitive earth.
Their apparatus consisted of a closed tube connecting two chambers. The upper chamber contained a mixture of gasses (resembling earth's primitive atmosphere). Electrodes discharged sparks through this mixture (simulating lighting). Condensers cooled the gasses causing water droplets to form, which passed into the second heated chamber (the ocean). Any complex molecules formed in the atmosphere chamber would be dissolved in these droplets and carried to the ocean chamber, where samples were removed for analysis.
Miller and Urey found that within a week, 15% of the carbon originally present as methane gas had converted into other simple carbon compounds. These compounds then combined to form simple molecules and more complex molecules containing carbon-carbon bonds, including the amino acids glycine and alanine. Amino acids are the building blocks of proteins, and proteins are one of the major kinds of molecules of which organisms are composed. Their experiment was designed to prove that the key molecules of life could have formed in the atmosphere of the early earth.
Biology and Evolutionary Theory Fossil Records Ecology Limnology Evolution & Faith Natural Selection Understanding Evolution
Classification, or taxonomy, is a system of categorizing living things. There are seven divisions in the system:
Kingdom Phylum or Division Class Order Family Genus Species Kingdom is the broadest division. There is no agreement about the number of kingdoms, but most scientists support a four-kingdom (Animalia, Plantae, Protista, and Monera) or five-kingdom (Animalia, Plantae, Protista, Monera, and Fungi) system. Now technology has progressed and other scientists have developed the six-kingdom model (as seen below) which is currently being published in new biology textbooks.
For our purposes we will use the five-kingdom system which combines the kingdom Eubacteria and Archaebacteria as simply Monera. But, as scientists, know both systems.
It is true most known prokaryotes are bacteria, however, scientists have recent knowledge that prokaryotic life is represented by two more distinct domains. I have included the diversity between these two domains but we will not divide the two in this course.
Classification of Living Things
DOMAIN
KINGDOM
Eubacteria
Archaebacteria
Protista
Fungi
Plantae
Animalia
CELL TYPE
Prokaryote
Prokaryote
Eukaryote
Eukaryote
Eukaryote
Eukaryote
CELL STRUCTURES
Cell walls
with peptidoglycanCell walls
without peptidoglycanCell walls of cellulose in some; some have chloroplasts
Cell walls of chitin
Cell walls of cellulose; chloroplasts
No cell walls or chloroplasts
NUMBER OF CELLS
Unicellular
Unicellular
Most unicellular; some colonial; some multicellular
Most multicellular; some unicellular
Multicellular
Multicellular
MEMBRANE LIPIDS Unbranched hydrocarbons Some branched hydrocarbons Unbranched hydrocarbons Unbranched hydrocarbons Unbranched hydrocarbons Unbranched hydrocarbons RNA POLYMERASE one kind several kinds several kinds several kinds several kinds several kinds INITIATOR AMINO ACID PROTEIN SYNTHESIS Formylmethionine Methinonine Methinonine Methinonine Methinonine Methinonine INTRONS (NONCODING FOR GENE PARTS) Absent Present in some genes Present Present Present Present HISTONES ASSOCIATED WITH DNA Absent Present Present Present Present Present RESPONSE TO ANTIBOTICS Growth inhibited Growth NOT inhibited Growth NOT inhibited Growth NOT inhibited Growth NOT inhibited Growth NOT inhibited MODE OF NUTRITION
Autotroph or heterotroph
Autotroph or heterotroph
Autotroph or heterotroph
Heterotroph
Autotroph
Heterotroph
ABILITY TO GROW AT TEMP. >100o C No Some species No No No No EXAMPLES
Streptococcus, Escherichia coli
Methanogens, halophiles
Amoeba, Paramecium, slime molds, giant kelp
Mushrooms, yeasts
Mosses, ferns, flowering plants
Sponges, worms, insects, fishes, mammals
The lowest, most basic division is species, which consists of organisms that resemble each other and are capable of interbreeding to produce fertile offspring. The system scientists use to name species is called binomial nomenclature. It is done by putting together a creature's genus name and species name. The first is the genus, the second is the species.
Animalia
The first word (Genus) is always capitalized, the second word (species) is not, and both should be italicized. For instance, humans are referred to as Homo sapiens, bearded dragons are referred to as Pogona vitticeps, and corn snakes are referred to as Pantherophis guttatus (formerly Elaphe guttata).
Classification of Four Organisms
Corn
Whale
Shark
Humpback Whale
Spider Monkey
Kingdom
Plantae
Animalia
Animalia
Animalia
Phylum
Anthophyta
Chordata
Chordata
Chordata
Class
Monocotyledones
Chondrichthyes
Mammalia
Mammalia
Order
Commelinales
Squaliformes
Cetacea
Primates
Family
Poaceae
Rhincodontidae
Balaenopteridae
Atelidae
Genus
Zea
Rhincodon
Megaptera
Ateles
Species
Zea mays
Rhinacodon typus
Megaptera novaeangilae
Ateles paniscus
Plantae
Check out the spikes on this tree
Bird of Paradise
Plants Database
Invertebrate & Vertebrate Survey
Invertebrates:
Sponges, Cnidarians, and Unsegmented Worms
Mollusks and Annelids
Arthropods
Echinoderms and Invertebrate Chordates
Vertebrates:
Fish and Amphibians
Reptiles and Birds
Mammals
Ornithology
The study of birds
Interesting Facts:
Mark Catesby was the famous Naturalist (America’s first natural scientist) in Williamsburg, VA in the 1700s, whom I (Mrs. King) am privileged to be related. He was the brother of Elizabeth Catesby Cocke, my ancestor who was married to Dr. William Cocke, a prominent physician and Secretary of State under Gov. Spotswood. They all lived in Williamsburg, VA during the 18th century. I have my sister, Dr. Patricia L. Petitt, USAMRIID, to thank for her diligent work in our family's genealogy who supplied me with this information.
"English naturalist Mark Catesby (1683-1749) is considered by many to be the founder of American ornithology. Catesby made two expeditions to the southern part of colonial America in the first half of the eighteenth
century. Based on his observations and collections, he published The Natural History of Carolina, Florida, and the Bahama Islands, which stood for more than a century as the primary natural history of British North America. His images of flora and fauna influenced the style of later artists, notably John Abbot and John James Audubon" (Morris Museum of Art, 2004).
Metamorphosis
Types of Metamorphosis
Complete & Incomplete
Insects Metamorphosis Insect Facts
Dissection
Dissection is a process used in science class to help the student understand structure and function of plants & animals organs.
Dissections in our class are performed with extreme care, using virtual labs when at all possible.
Annelid Dissection
Squid Dissection
Class - Cephalopoda
Images Virtual Dissection
Starfish Dissection
Phylum - ECHINODERMATA
Class - Asteroidea
Virtual Dissection
Clam Dissection
Class: Pelecypoda
Mollusk Data
Kingdom Animalia
Subkingdom Eumetazoa - mollusks have organs
Branch Bilateria - they have bilateral symmetry
Grade Coelamata - they have body cavities
Subgrade Schizocoela - the mesoderm pouches to form that body cavity
Class Polyplacophora - "bearer of many plates"
Class Pelecypoda - "hatchet footed"
Class Gastropoda - "stomach footed"
Class Cephalopoda - "head footed"
Virtual Dissection
Crayfish Dissection
Images Penn State Dissection Protocol Lab Images Virtual Lab animation
Frog Dissection
Frogs belong to the class Amphibia, which means "double life."
The 3 orders that make up that class are
Caudata (salamander and newts)
