Wednesday, August 19, 2009

The Enzymes

A molecule of DNA polymerase binds to one another to one strand of the DNA and begins moving along in the 3' to 5' direction using a template for assembling a leading strand of nucleotides and reforming a double helix



The porpuse of the LAB BENCH was to measure the amount of dissolved oxygen in water samples at different temperature. Analyse the effect of varying amounts of light on primary productivity.

Mutualism, Parasitism and Commensaism

Mutualism: a relationship between two species of organisms in which both benefit from the association
ex:clownfish, sea anemones, termites and intestinal flagellates

Parasitism: a relatioship between organisms in which one lives as a parasite on another
ex:tick, lice, and worms

Commensalism: a relationship between two kinds of organisms in which one obtain food or another benefits from the other without damaging or benefiting
ex: remora, sharks and barnacles.

Four Organic Compounds

Carbohydrates

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

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

Evidence of Evoution

  1. Fossil evidence indiates that evolution has ocurred
  2. The Anatomical Record
  3. The Molecular Record
  4. Convegent & Divergent Evolution

Natural Selection

Natural selection
(differential reproduction genotypes)
Is the process in the theory of evolution where organisms that are best suited to their environment survive and pass on their genetic characteristics in increasing number while organisms that are less adapted tend to be eliminated.

**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!**

Darwins vs. Lamarck theory of evolution

Darwins

  • Individuals display differences
  • Shortage of food leads them to fight for existence
  • Individuals with superior differences have more change to reach adulthood, reproduce and transmit these variations to their offspring

Lamarck's

  • Environmental changes generate new needs
  • these needs determine to use or disuse of some organs
  • such organs develop or are diminished
  • the acquired characters are hereditary

*Contrast to Lamarck's evolutionary, Darwin's theory of evolution proposed natural selection as the basis of evolution and human origin*

Phloem and xylem


Both

*makeup the big transportation

system of vascular plants.

*both are tubular structures

Phloem

*transport water and food

xylem

*imports water and minerals

Human Body Systems









Respiratory: this system consists of the trachea, a passageway of air from the mouth or nasal cavity. The purpose of the respiratory system is to provide the body with oxygen and to dispel carbon dioxide from the body.









Muscular: the three types of muscles are smooth(found in internal organs and blood muscles),cardiacfound in the heart), and skeletal(attached to bones). Smooth muscles allows for the contraction of organs, cardiac muscle is responsable for the pumping of the heart and skeletal allows all movement of the body.







Excretory/ Urinary: consists of the kidneys, uteres, the urinary bladder and the urethra. The excretory system is ti filter the blood and remove major waste products such as ammonia and urea. Responsible for regulating the pH of the blood.





Immune/ Lymphatic: the lymph nodes and lymph vessels are founf throughout the body and help filter out antigens, disease causing microorganisms. The tonsils, thymus gland, spleen, and bone marrow are also involved in the immune system. The function of the immune system is to protect the body from infections and antigens.









Wednesday, August 12, 2009

Human Body Systems

Reproductive system consists of the testis, vas deferens, urethra, and the penis(male) ovary, uterus, and the vagina (female). Its function in males and females is to perpectuate species trough reproduction.




Intergumentary(skin) composed of two parts epidemis, dermis. The skin is responsible for regulating your body temperature, serves as a protective layer to the underlying tissues.









Skeletal system is compromised with two parts, axial epidermis, appendicular skeleton.Provides a framework for the tissue of the body, upper organs.

Human Body Systems










Circulatory system consists of the heart, arteries, veins, capillaries and blood. The function of the circulatory system is to transport blood to every part of the body. In the blood are all the necessary gases, nutrients,and waste products; which are all transported to the necessary parts of the body.






Digestive system begins with the mouth, then with the esophagus, stomach, small intestine, large intestine and rectum. The function of the digestive system is to digest food and provide vital nutrients to the body,help regulates metabolism and to eliminate wastes.










Nervous system is broken down into two parts, the central and the peripheral. The brain and spinal cord combine to create the central nervous system. The nervous system controls all bodily activities.








Endocrine system consists of a network of glands including the pituitary, thyroid, thymus, pancreas, testes, ovaries, adrenal,and parathyroid glands. The glands secrete hormones that play a role in the regulation of digestion, metabolism, and homeostasis.

3 Domains In Life

1. Domain Archaea- found in the harshest environments on Earth
2. Domain Bacteria- most species even play beneficial holes for humans by producing antibiotic and food
3. Domain Eukarya- four kindoms of Eukaryotes
*Protista
*Fungi
*Plantae
*Animalia
Protista- single called eukaryotes
Fungi- mushrooms,bread molds,water molds
Plantae-Flowerings plants, mosses
Animalia-arthropods ,sponges, jelly fish, insects

Incomplete Dominance


Incomplete Dominance is a form of intermediate inheritance in which heterozygous alleles are both expressed, resulting in a combined phenoype.

*In cross pollination experiments between red and white snapdragon plants, the resulting offspring are pink.

Genotype & Phenotype

Genotype: they control everything from the formation of protein macromolecules to the regulation of metabolism and synthesis.
Phenotype: anything that is part of the observable structure, function or behavior of a living organism
*the genotype codes for the phenotype*

Autosomes & Sex 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.

Transcription in Eukaryotic and Eukaryotic

Eukaryotic : transcription occurs in the nucleus to produce a pre-mRNA molecule.
same: *both have DNA as their genetic material
*both are membrane bound
*both have ribosomes
*have similar basic metabolism
Prokaryptic: translation has to be together with aranslation. When bacterial genes are transcribed their transcripts can inmediately be translated

Process of translation

Translation is divided into 3 stages: initiation, elongation and termination. Initiation is the binding of a specific initiator methionyl tRNA and then RNA to the small ribosomal submit. The large ribosomal subunit then joins the complex forming a functional ribosome on which enlongation of the polypeptide chains proceeds.
*a number of specific nonribosomal proteins are also require for the various stages of the translation process*

Transcription in Eukaryotic cells

Transcription in eukaryotic cells is the synthesis of an RNA copy of a segment of DNA. RNA is synthesizedby the enzyme RNA polymerase.
In a eukaryotic cell transcription occurs in the nucleus(transcription occurs in the cytoplasm).
Transcription occurs in the nucleus to produce a pre-mRNA molecule. The pre-mRNA is processed to produce the nature mRNA which exists the nucleus and is translated in the cytoplasm.

DNA replication & enzymes

DNA replication starts with the "unzipping" of the parent molecule as the hydrogen bonds between the base pairs are broken.
A molecule of DNA polymerase binds to one strand of the DNA and begins moving along in the 3' to 5' direction using a template for assembling a leading strand of nucleotides and reforming a double helix.

DNA & RNA

DNA RNA
- deoxyribonucleic acid -ribonucleic acid
-deoxyribose sugar present -ribose sugar present
-2 double chains held in -single stranded
a double helix by hydrogen -Uracil (U) present
bonds
-contains a chemical code
or message that must be
transcribed

Mitosis & Binary Fission




Binary Fission is the method by which bacteria reproduce. DNA molecule is replicated then the cell replicated, then the cell splits into two identical cells, each containing a original cell copy of DNA.


Mitosis deals with segregation of chromosomes and organelles into daughter cells. Mitosis forms identical daughters cells by replicating and dividing the original chromosome.
Meiosis has to do with a deduction in the amount of genetic material, mitosis is the cell division by which germ cells(egg and sperm)are produced.

The Cell Cycle


The cell grows and duplicates its DNA and centrioles,then the chromain condenses into chromosomes. The chromosomes line up across the middle of the cell , the sister chromatids separate into individual chromosomes and move apart. Chromosomes gather at opposite ends of the cell, the cell membrane pinches the cytoplasm in half.

Interphase lasts at least 12 to 24 hr in mammalian tissue during this period the cell synthesize RNA producing protein and getting big.

Mitosis is shorter than interphase, the cell growths and protein production stops. The cell's energy is focused on the complex and orderly division into two similar daughter cells.

*two main events of the cellular reproduction are the copying of cellular components and the cleavage of the cell*

Tuesday, August 11, 2009

Catabolic and Anabolic Reactions


Catabolic reaction releases energy that is used to drive chemical reactions, breaks macromolucules into constituent individual subunit.

*catalysed by the enzyme

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

Anabolic reaction building up larger molecules from smaller ones.

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


Alive? Viruses, Prions, Viroids

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

Viruses, Prions & Viroids






Viruses Bolddepend on the host cell that they infect to produce, found outside of host cells, viruses exist as a protein coat or capsid sometimes enclosed within a membrane. A virus can insert its genetic material into its host taking over the host functions.



Prions a disease causing agent that is neither bacterial nor fungal nor viral and contains no genetic material. Prions are responsable for number of degenerative brian diseases.



Viroids small agents of infectious disease, acellular, identified as an infectious agent in plants.



(Viroids and Prions do not have protein capsids protecting their nucleic acid)

Transport is essential for 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 &A ctive transport


Passive transport does not require expenditure of metabolic energy, materials flow down the concentration gradient.
Active transport uses energy (ATP)and materials flow against the concentration gradient.

The 4 types of cellular mechanisms











The four types are dffusion, osmosis, facililated diffuison, and active transport. Diffusion is when someone wears perfume and the aromatic molecules spread concentrating on that persons skin, the aroma disperses. Osmosis is when water moves through a semipermeable membrane from an area of higher concentration to an area of low concentration. Facilitated diffusion is a transport protein in the membrane enhances the transport of the substance across the membrane. Active transport uses energy in the form of ATP and materials flow against the concentration gradient.

Prokariotic and Eukariotic Cells


Prokayiotic cells and eukaryotic cells are different. They differ in their appareance, reproduction andmetabolism. Prokaryotic cells differ from eukaryotic cells because they don't have a membrane boud nucleus and their genetic information is stored is a circular loop called a plasmid. Eukaryotic cells are distinguished by their nucleus, eukaryote cells are present in the animal cells and on the plants. Prokaryote cells feature three shapes;rod shaped, spherical, and spiral.