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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:
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Keep good records of all investigations and activities |
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Record notes from text material and lectures/discussions |
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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
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Respiration
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Where
In cholorophyll-bearing cells |
Where: In all cells
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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
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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
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British Naturalist | ||||
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On The Origin of Species
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Presented evidence demonstrating that the process of evolution has been taking place for millions of years
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Gregor Mendel
Father of Genetics
1822 - 1884
Mendelian Genetics
Postulates:
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Unit Factors ( genes) come in pairs |
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Dominance vs. recessiveness |
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Segregation of alleles into gametes of equal frequency |
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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.
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Classification of Living Things |
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DOMAIN |
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KINGDOM |
Eubacteria |
Archaebacteria |
Protista |
Fungi |
Plantae |
Animalia |
|
CELL TYPE |
Prokaryote |
Prokaryote |
Eukaryote |
Eukaryote |
Eukaryote |
Eukaryote |
|
CELL STRUCTURES |
Cell walls with peptidoglycan |
Cell walls without peptidoglycan |
Cell 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 |
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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).
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Classification of Four Organisms |
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Corn |
Whale Shark |
Humpback Whale |
Spider Monkey |
|
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Kingdom |
Plantae |
Animalia |
Animalia |
Animalia |
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Phylum |
Anthophyta |
Chordata |
Chordata |
Chordata |
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Class |
Monocotyledones |
Chondrichthyes |
Mammalia |
Mammalia |
|
Order |
Commelinales |
Squaliformes |
Cetacea |
Primates |
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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
| 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
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