Reference

http://www.emc.maricopa.edu/faculty/farabee/biobk/biobooktoc.html

http://www.biology.arizona.edu/

http://www.sciencedaily.com/news/plants_animals/evolution/

Parasitism, Commensalism, and Mutualism

•Mutualism is a biological interaction between two organisms, where each individual derives a fitness benefit.
An example - a bees polinate trees -- the bee gets food, the tree gets pollinated.

•Commensalism is the relation between two different kinds of organisms when one receives benefits from the other without damaging it.
An example -a flatworm attaching to the horsecrab and eating the crab's food while the crab is unaffected.

•Parasitism is the relation between two different kinds of organisms in which one receives benefits from the other by causing damage to it.
An example -a flea and a dog; flea gets home/food and the dog is harmed because the flea feeds on its blood

Four Organic Compounds

Lipids

• molecules composed of carbon, hydrogen and oxygen
• lipids include steroids, waxes, and fat
• the enzyme lipase breaks down fats into falty acids and glycerol in the human digestive system

Protein

• proteins are composed of amino acidswhich contain carbon, hydrogen, oxygen and nitrogen atoms
• amino acids also contain sulfur phosphorous, iron and copper

Nucleic Acids

• large molecules
• composed of smaller units called nucleotides
• live organisms have 2 important nucleic acids DNA or RNA

Carbohydrates

• molecules composed of carbon, hydrogen and oxygen
• referred to as sugars
• C6H12O6

Evidence for Evolution

Science does this by continuously comparing its theories objectively with evidence in the natural world. When theories no longer conform to the evidence, they are modified or rejected in favor of new theories that do conform. In other words, science constantly tries to prove its assumptions to be false and rejects implausible explanations. In this way, scientific knowledge and understanding grow over time. Religious explanations for the order of things are not science because they are based primarily on faith and do not subject themselves to be objectively falsified. Because of this fundamental difference in the approach to understanding our natural world, the U.S. Supreme Court in effect decided in 1987 that the Biblically based "creation science" is not a science and cannot be taught as such in public schools as an alternative or in addition to the mainstream evolutionary theory of the biological sciences. However, religious creation stories and the idea of "intelligent design" can be taught in philosophy, religion, or history courses. Religion and Science provide different approaches to knowledge. It is important to understand both.

The evidence for evolution has primarily come from four sources:

1.	the fossil record of change in earlier species
2.	the chemical and anatomical similarities of related life forms
3.	the geographic distribution of related species
4.	the recorded genetic changes in living organisms over many generations

Natural selection

Natural Selection is when a living thing is born with something different than the rest of their species (more fur, longer neck or legs, ect) that gives them an advantage and helps them live better and longer in their enviroment. They pass it onto their children and their children pass it onto their children making a different species.
*the rat snake has different populations in eastern North America. All compromise one specie because mating can occur between adjacent populations causing to share a common genepool.
**are well documented both by obsserving and through the fossil record!**

Darwin's Theory Vs. Lamarck's Ideas Of Evolution

Jean-BaptisteLamarck proposed that organisms could pass on to their offspring traits that where acquired during their lifetime. This has come to be known as inheritance of acquired characteristics.

On the other hand Charles Darwin recognized the main mechanism for evolution: Natural Selection. Natural Selection is the process by which favorable heritable traits become more common in successive generations of a population and unfavorable heritable traits become less common, due to differential reproduction. That is: given a certain population, those individuals who are more fit to the selective pressure(s) by their habitat (in a given time and space) will leave more descendants than those less fit

In short, Lamarck thought that changes were acquired during the life of a parent organism and then transmitted to their offspring while Darwin deducted that changes were already present in the parent organisms, and that the best adapted to that situation survived to breed, which meant that those genetic changes become common in the following generations

Read more: http://wiki.answers.com/Q/What_are_the_differences_between_Darwin's_theory_of_Evolution_and_Lamarck's_theory_of_Evolution#ixzz1VijtrisN

Phloem Vs. Xylem

	Phloem	Xylem	Hide AllShow All
Occurrence:	Roots, stems and leaves	Roots, stems and leaves	hide
Additional Functions:	Forms vascular bundles with xylem	Forms vascular bundles with phloem and gives mechanical strength to plant due to presence of lignified cells.	hide
Elements:	Sieve tubes, companion cells, phloem parenchyma, bast fibers, intermediary cells	Tracheids, vessel elements, xylem parenchyma, xylem sclerenchyma	hide
Nature of tissue:	Living tissue	Non living tissue at maturity	hide
Movement:	Bidirectional	Unidirectional (upward)	hide
Function:	Transportation of food and nutrients from leaves to storage organs and growing parts of plant.	Water and mineral transport from roots to aerial parts of the plant.	hide
Structure:	Tubular with soft walled cells	Tubular with hard walled cells	hide

---

Phloem and xylem are complex tissues that perform transportation of food and water in a plant. They are the vascular tissues of the plant and together form vascular bundles. They work together as a unit to bring about effective transportation of food, nutrients, minerals and water.

[edit] Sap components

Xylem sap contains water, inorganic ions and a few organic chemicals. Phloem sap contains water and sugars.

Differences between Xylem and Phloem vessels

 Functions of xylem vs phloem

Xylem transports water and soluble mineral nutrients from roots to various parts of the plant. It is responsible for replacing water lost through transpiration and photosynthesis. Phloem translocates sugars made by photosynthetic areas of plants to storage organs like roots, tubers or bulbs.

 

 Video

This video explains the biological makeup of xylem and phloem and their role in plant transport.

 

Four Plan Divisions

-Bryophites: Moss, little better than algae, no sclerenchyma, motile gametes.
-Pteridophytes: Ferns. Better, but still backward. They have advanced vascular tissues, sclerenchyma, but reproduce via sporulation, and have two different phases in their life cycle. The gametophyte phase is pronounced, containin a prothallus.
-Coniferophytes: Pine trees. They contain sophisticated vasculature and root systems. They have a markedly reduces gametophytic phase, but have no triploid endosperm.
-Anthophytes: Most advanced. They're any tree that's not a conifer. They have flowers, and triploid endosperms in their seeds. They are divided into monocots and dicots, of which the former are more advanced.

Human Body Systems

Skeletal System:
The main role of the skeletal system is to provide support for the body, to protect delicate internal organs and to provide attachment sites for the organs.
Major Organs -
Bones, cartilage, tendons and ligaments.






Muscular System:
The main role of the muscular system is to provide movement. Muscles work in pairs to move limbs and provide the organism with mobility. Muscles also control the movement of materials through some organs, such as the stomach and intestine, and the heart and circulatory system.

Major Organs-
Skeletal muscles and smooth muscles throughout the body.




Circulatory System:
The main role of the circulatory system is to transport nutrients, gases (such as oxygen and CO₂), hormones and wastes through the body.
Major Organs:
Heart, blood vessels and blood.







Nervous System:
The main role of the nervous system is to relay electrical signals through the body. The nervous system directs behaviour and movement and, along with the endocrine system, controls physiological processes such as digestion, circulation, etc.
Major Organs:
Brain, spinal cord and peripheral nerves






Respiratory System:
The main role of the respiratory system is to provide gas exchange between the blood and the environment. Primarily, oxygen is absorbed from the atmosphere into the body and carbon dioxide is expelled from the body.
Major Organs:
Nose, trachea and lungs






Digestive System:
The main role of the digestive system is to breakdown and absorb nutrients that are necessary for growth and maintenance
Major Organs:
Mouth, esophagus, stomach, small and large intestines.






Excretory System:
The main role of the excretory system is to filter out cellular wastes, toxins and excess water or nutrients from the circulatory system
Major Organs:
Kidneys, ureters, bladder and urethra








Endocrine System
The main role of the endocrine system is to relay chemical messages through the body. In conjunction with the nervous system, these chemical messages help control physiological processes such as nutrient absorption, growth, etc.
Major Organs:
Many glands exist in the body that secrete endocrine hormones. Among these are the hypothalamus, pituitary, thyroid, pancreas and adrenal glands.





Reproductive System:
The main role of the reproductive system is to manufacture cells that allow reproduction. In the male, sperm are created to inseminate egg cells produced in the female.
Major Organs:
Female (top): ovaries, oviducts, uterus, vagina and mammary glands.
Male (bottom): testes, seminal vesicles and penis.

Lymphatic/Immune System:
The main role of the immune system is to destroy and remove invading microbes and viruses from the body. The lymphatic system also removes fat and excess fluids from the blood.
Major Organs:
Lymph, lymph nodes and vessels, white blood cells, T- and B- cells.

Domains Of Life

three distinct domains of organisms in nature: Bacteria, Archaea, and Eukarya

1. The Archaea (archaebacteria)

The Archaea possess the following characteristics:

• Archaea are prokaryotic cells.
• Unlike the Bacteria and the Eukarya, the Archaea have membranes composed of branched hydrocarbon chains (many also containing rings within the hydrocarbon chains) attached to glycerol by ether linkages (see Fig. 1).
• The cell walls of Archaea contain no peptidoglycan.
• Archaea are not sensitive to some antibiotics that affect the Bacteria, but are sensitive to some antibiotics that affect the Eukarya.
• Archaea contain rRNA that is unique to the Archaea as indicated by the presence molecular regions distinctly different from the rRNA of Bacteria and Eukarya.

Archaea often live in extreme environments and include methanogens, extreme halophiles, and hyperthermophiles. One reason for this is that the ether-containing linkages in the Archaea membranes is more stabile than the ester-containing linkages in the Bacteria and Eukarya and are better able to withstand higher temperatures and stronger acid concentrations.

2. The Bacteria (eubacteria)

The Bacteria possess the following characteristics:

• Bacteria are prokaryotic cells.
• Like the Eukarya, they have membranes composed of unbranched fatty acid chains attached to glycerol by ester linkages (see Fig. 1).
• The cell walls of Bacteria, unlike the Archaea and the Eukarya, contain peptidoglycan.
• Bacteria are sensitive to traditional antibacterial antibiotics but are resistant to most antibiotics that affect Eukarya.
• Bacteria contain rRNA that is unique to the Bacteria as indicated by the presence molecular regions distinctly different from the rRNA of Archaea and Eukarya.

Bacteria include mycoplasmas, cyanobacteria, Gram-positive bacteria, and Gram-negative bacteria.

3. The Eukarya (eukaryotes)

The Eukarya (also spelled Eucarya) possess the following characteristics:

• Eukarya have eukaryotic cells.
• Like the Bacteria, they have membranes composed of unbranched fatty acid chains attached to glycerol by ester linkages (see Fig. 1).
• Not all Eukarya possess cells with a cell wall, but for those Eukarya having a cell wall, that wall contains no peptidoglycan.
• Eukarya are resistant to traditional antibacterial antibiotics but are sensitive to most antibiotics that affect eukaryotic cells.
• Eukarya contain rRNA that is unique to the Eukarya as indicated by the presence molecular regions distinctly diffThe Eukarya are subdivided into the following kingdoms:
  

  a. Protista KingdomProtista are simple, predominately unicellular eukaryotic organisms. Examples includes slime molds, euglenoids, algae, and protozoans.
  b. Fungi KingdomFungi are unicellular or multicellular organisms with eukaryotic cell types. The cells have cell walls but are not organized into tissues. They do not carry out photosynthesis and obtain nutrients through absorption. Examples include sac fungi, club fungi, yeasts, and molds.
  c. Plantae Kingdom
  Plants are multicellular organisms composed of eukaryotic cells. The cells are organized into tissues and have cell walls. They obtain nutrients by photosynthesis and absorption. Examples include mosses, ferns, conifers, and flowering plants.
  d. Animalia KingdomAnimals are multicellular organisms composed of eukaryotic cells. The cells are organized into tissues and lack cell walls. They do not carry out photosynthesis and obtain nutrients primarily by ingestion. Examples include sponges, worms, insects, and vertebrates.
  erent from the rRNA of Archaea and Bacteria.

Incomplete Dominance

Incomplete dominance is a form of intermediate inheritance in which one allele for a specific trait is not completely dominant over the other allele. This results in a combined phenotype.

In cross-pollination experiments between red and white snapdragon plants, the resulting offspring are pink. The dominant allele that produces the red color is not completely expressed over the recessive allele that produces the white color.

Genotype & Phenotype

Thegenotype of an organism is the class to which that organism belongs as determined by the description of the actual physical material made up of DNA that was passed to the organism by its parents at the organism's conception. For sexually reproducing organisms that physical material consists of the DNA contributed to the fertilized egg by the sperm and egg of its two parents. For asexually reproducing organisms, for example bacteria, the inherited material is a direct copy of the DNA of its parent. The phenotype of an organism is the class to which that organism belongs as determined by the description of the physical and behavioral characteristics of the organism, for example its size and shape, its metabolic activities and its pattern of movement.

The genotype is the descriptor of the genome which is the set of physical DNA molecules inherited from the organism's parents. The phenotype is the descriptor of the phenome, the manifest physical properties of the organism, its physiology, morphology and behavior.

Autosomes Vs. Chromosomes

Autosomes are other or any chromosomes other than the sex chromosomes. Sex chromosomes are the y-chromosome and x-chromosome. Normally people have 22 pairs of autosomes in every cell (together with 2 sex chromosomes an x and a y, y in the male and x in the female -for a total of 46 chromosomes.

Allele Vs. Gene

A gene is a part of the DNA. Alleles on the other hand refer to different versions of the same gene. There are other more subtle differences between the two and this is what we are going to explore on this page:

• Genes are the different parts of the DNA that decide the genetic traits a person is going to have. Alleles are the different sequences on the DNA-they determine a single characteristic in an individual.
• Another important difference between the two is that alleles occur in pairs. They are also differentiated into recessive and dominant categories. Genes do not have any such differentiation.
• An interesting difference between alleles and genes is that alleles produce opposite phenotypes that are contrasting by nature. When the two partners of a gene are homogeneous in nature, they are called homozygous. However, if the pair consists of different alleles, they are called heterozygous. In heterozygous alleles, the dominant allele gains an expression.
• The dominance of a gene is determined by whether the AA and Aa are alike phenotypically. It is easier to find dominants because they express themselves better when they are paired with either allele.
• Alleles are basically different types of the same gene. Let's explain this to you in this way- If your eye color was decided by a single gene, the color blue would be carried by one allele and the color green by another. Fascinating, isn't it?
• All of us inherit a pair of genes from each of our parents. These genes are exactly the same for each other. So what causes the differences between individuals? It is the result of the alleles.
• The difference between the two becomes more pronounced in the case of traits. A trait refers to what you see, so it is the physical expression of the genes themselves. Alleles determine the different versions of the genes that we see. A gene is like a machine that has been put together. However, how it will works will depend on the alleles.

Both alleles and genes play an all important role in the development of living forms. The difference is most colorfully manifest in humans of course! So next time you see the variety of hair color and eye color around you, take a moment and admire the phenomenal power of both the gene and the allele

Building a Protein: Transcription

proteins is very much like building a house:

• The master blueprint is DNA, which contains all of the information to build the new protein (house).
• The working copy of the master blueprint is called messenger RNA (mRNA), whic­h is copied from DNA.
• The construction site is either the cytoplasm in a prokaryote or the endoplasmic reticulum (ER) in a eukaryote.
• The building materials are amino acids.
• The construction workers are ribosomes and transfer RNA molecules.

Let's look at each phase of the new construction more closely.
In a eukaryote, DNA never leaves the nucleus, so its information must be copied. This copying process is called transcription and the copy is mRNA. Transcription takes place in the cytoplasm (prokaryote) or in the nucleus (eukaryote). The transcription is performed by an enzyme called RNA polymerase. To make mRNA, RNA polymerase:

1. Binds to the DNA strand at a specific sequence of the gene called a promoter
2. Unwinds and unlinks the two strands of DNA
3. Uses one of the DNA strands as a guide or template
4. Matches new nucleotides with their complements on the DNA strand (G with C, A with U -- remember that RNA has uracil (U) instead of thymine (T))
5. Binds these new RNA nucleotides together to form a complementary copy of the DNA strand (mRNA)
6. Stops when it encounters a termination sequence of bases (stop codon)

mRNA is happy to live in a single-stranded state (as opposed to DNA's desire to form complementary double-stranded helixes). In prokaryotes, all of the nucleotides in the mRNA are part of codons for the new protein. However, in eukaryotes only, there are extra sequences in the DNA and mRNA that don't code for proteins called introns. This mRNA is then further processed:

• Introns get cut out
• The coding sequences get spliced together
• A special nucleotide "cap" gets added to one end
• A long tail consisting of 100 to 200 adenine nucleotides is added to the other end

No one knows why this processing occurs in eukaryotes. Finally, at any one moment, many genes are being transcribed simultaneously according to the cell's needs for specific proteins.
The working copy of the blueprint (mRNA) must now go the construction site where the workers will build the new protein. If the cell is a prokaryote such as an E. coli bacterium, then the site is the cytoplasm. If the cell is a eukaryote, such as a human cell, then the mRNA leaves the nucleus through large holes in the nuclear membrane (nuclear pores) and goes to the endoplasmic reticulum (ER).
Next, we'll learn about translation -- the assembly process.

RNA (Ribonucleic Acid)

RNA is the other nucleic acid. It differs from DNA in three major ways:

• The sugar is ribose instead of deoxyribose
• There is only one strand instead of two
• RNA has uracil (U) instead of thymine. So, the base pairs in RNA are cytosine with guanine and adenine with uracil.

In a prokaryotic cell (one with no internal membrane-bound organelles like a bacterium), both DNA and RNA are found in the cytoplasm. In a eukaryotic cell(one with internal membrane-bound organelles, like humans), RNA can be found in the nucleus and cytoplasm, while DNA is only found in the nucleus.

DNA Replication Process

http://www.youtube.com/watch?v=teV62zrm2P0

DNA & RNA

DNA -

• deoxyrionucleic acid and contains the 5 carbon sugar deoxyribose
• a double stranded molecule
• contains 4 bases Adenine (A) , Cytosine (C), Guanine (G) and Thymine (T).
• DNA, being double stranded is too large to pass out of the nuclear pores and so is confined to the nucleus.
• DNA can undergo self replication, RNA can't

RNA-

• RNA is ribonucleic acid and contains the 5 carbon sugar ribose.
• RNA is single stranded
• In RNA Thymine is replaced by Uracil(U) but also contains A, C and G.
• has several types: Messenger RNA(mRNA), Transfer RNA (tRNA) and Ribosomal (rRNA)
• mRNA is copied from one strand of DNA by a process called Transcription

-Both DNA are composed of sub units called nucleotides.

-A Nucleotide has 3 sub units: A 5 carbon sugar, An inorganic phosphate and one of four bases.

-The nucleotides in both DNA and RNA are linked by chemical bonds between the sugar of one nucleotide and the Phosphate of the next to form a 'sugar- phosphate backbone'.
-Proteins are coded for by sequences of three bases on the nucleic acid strands.
-A series of three bases on DNA is called a Triplet. On mRNA a sequence of three bases is called a codon and on tRNA it is called an anticodon.

Mitosis Vs. Meiosis

http://www.diffen.com/difference/Meiosis_vs_Mitosis

Mitosis is the division of the nucleus in a diploid cell (that is, a cell containing 2 sets of chromosomes). It occurs in eukaryotic cells. Generally, it is followed by cytokinesis, which is the splitting of the cell membrane, thus completeing the process of 'duplicating' or dividing the cell.

Binary Fission is the form of asexual reproduction in single-celled organisms. It is the division of one cell into two cells of the same size. This happens in prokaryotic cells, as opposed to eukaryotic cells

Cell Cycle

The two larger phases of the cell cycle, interphase and Mitosis. Mitosis is the part of the cell cycle when the cell prepares for and completes cell division. During interphase, appropriate cellular components are copied. Interphase is also a time of checkpoints to make sure that the cell is ready to proceed into mitosis. Both of these two phases have further sub-divisions. Since the cell cycle is a "cycle" it has no distinct beginning or ending. Cells are continually entering and exiting the various phases of the cycle.

Catabolic and anabolic reactions

Catabolic and anabolic reactions are metabolic processes. Both the capture and use of energy by organisms involves a series of thousands of reactions (metabolism). A catabolic reaction is one that breaks down large molecules to produce energy; an example is digestion. An anabolic reaction is one that involves creating large molecules out of smaller molecules; an example is when your body makes fat out of extra nutrients you eat.

-catalysed by the enzyme

-beta- lactosidase, enzyme which breaks down lactose into galactose and glucose

-nucleotide been added onto a strand of DNA- the strand of DNA is lenghtened.

Viruses Prions, and Viroids

Viruses, Prions and Viroids may behave like living things, acellular particles. However, they are not consider to be living organisms because they are incapable of carriying out all life processes .

Viruses:

Viruses depend on the host cells that they infect to reproduce. When found outside of host cells, viruses exist as a protein coat or capsid, sometimes enclosed within a membrane. The capsid encloses either DNA or RNA which codes for the virus elements. While in this form outside the cell, the virus is metabollically inert.When it comes into contact with a host cell, a virus can insert its genetic material into its host, literally taking over the host's functions.






Prions:

Prions are unprecedented infectious pathogens that cause a group of invariably fatal neurodegenerative diseases by an entirely novel mechanism. Prion diseases may present as genetic, infectious, or sporadic disorders. Prions a disease causing agent that is neither bacterial nor fungal nor viral and contains no genetic material.




Viroids:

Viroids are infectious agents composed exclusively of a single piece of circular single stranded RNA which has some double-stranded regions.Because of their simplified structures both prions and viroids are sometimes called subviral particles. Viroids mainly cause plant diseases but have recently been reported to cause a human disease

Characteristics Of Life

http://www.slideshare.net/cgales/characteristics-of-life

Transport Essential to Life

Transport moves materials across the plasma membrane. Cells must import and export materials in order to maitain life sustaining activities this is why life is essential for life.

Passive Vs. Active Transport

Passive transport occurs when the concentration of something on one side of membrane is different from the concentration on the other side. It occurs when that substance can pass through the membrane, and always in the direction of more to less. No energy is required to make the substance move. This is like rolling a rock down a hill--it just does it on its own.

Active transport occurs from less to more. It requires energy for transport.
This is like rolling a rock up a hill--you have to push it the entire way!

Active transport requires energy, but passive transport requires none.

Active transport requires a special protein to make the transport occur, but passive transport requires none.

• Both involve the transport of a substance across a membrane, and the change in concentrations on different sides of a membrane. Both are also important to the proper functioning of a cell.

Cellular Transport Mechanisms

Diffusion-
Diffusion involves the movement of atoms across the cytolemma from a region of higher concentration to a region of lower concentration. Atoms move across the cell membrane by by going between the lipid molecules that make up the cell membrane. Small atoms diffuse the easiest across the membrane. No outside chemical energy is needed for simple diffusion.

Facilitated Diffusion-

Diffusion is facilitated by cell membrane proteins that provide a way for atoms or molecules to more easily diffuse across the membrane.




Osmosis-

Osmosis is the simple diffusion of water molecules across a semipermeable membrane. It occurs when the concentration of solutes in the solution on the two sides of a semipermeable membrane are different moves from a solution with a higher water concentration to a solution with lower water concentration.

Active Transport-

Chemical energy in the form of ATP is used to begin this process. A membrane carrier is used and the direction can be from high to low concentration or from low to high concentration. Active transport can enable a cell to move items across the membrane against a concentration gradient.

Eukaryotic and Prokaryotic Cells

Eukaryote cells are larger in diameter than prokaryote cells, a true nucleus and membrane enclosed organelles.
The cell walls of prokaryotes are thick as compared to that of a eukaryote, that sometimes are present. Eukaryotes have a cytoskeleton. Prokaryotes do not.
Cell division in eukaryotes is done by mitosis, and prokaryotes is done by binary fission.Prokaryotes are unicellular organisms. Eukariotes have many unicellular eukaryotes as well as more complexed multicellular ones.

They both have DNA as their genetic material. Both are membrane bound and contain ribosomes. They are diverse in forms and have a similar pattern of metabolism.