AP bio: Extreme Organism - Tubeworms

This picture is taken from: http://www.nsf.gov/news/special_reports/sfs/popup/life_vc_tubeworms.htm.)

Tubeworms (Riftia Pachyptila) live in the hydrothermal vents on the Pacific Ocean floor.  Here, the conditions are harsh.  The liquid from the hot vents mixes with the cold seawater.  Tubeworms look like giant lipsticks and can grow to approximately 3 meters (8 feet) tall.  They live in white tubes that are made of chitin, a tough, natural material that is chemically related to cellulose.

The chemical structure of chitin.  (This picture was taken from: http://academic.brooklyn.cuny.edu/biology/bio4fv/page/chitin.html.)

These strange creatures do not have a mouth, eyes, or a stomach.  They have a symbiotic relationship with the bacteria that live inside them, which ensures their survival.  The bacteria convert the chemicals from the vents into food for the worms through the process of chemosynthesis.  The red part of the tubeworm ia where it breaths.  The blood in this part of the tubeworm has a special kinds of hemoglobin that has a very high chance of reacting with the oxygen in the seawater.

AP bio: Bacterial Transformation and Transduction

The different strains of foreign DNA expressed in E. coli in Cohen and Boyer's experiment. 

Putting the bacteria into heat shock to induce them to take in foreign DNA.

One of the foreign DNA from the plasmid that is expressed in the transformed E. coli bacteria that grew on the bacteria culture plate.

Transformation: In this process, bacteria take in DNA molecules.  When they reproduce, the DNA molecule will also replicate with their own DNA.  The bacteria can be induced to take in certain DNA molecules, such as in Stanley Cohen and Herbert Boyer's experiment.  Cohen and Boyer inserted recombinant DNA into E. coli bacteria via a plasmid.  They created a heat shock by lowering and raising the temperature to make the bacteria take in the plasmid, then put the transformed bacteria into a culture plate.  The result is that the transformed bacteria would express the foreign DNA.

The process of bacterial transduction.

Transduction: In this process, bacteria transfer foreign DNA to each other via a virus.  When bactiophages infect a bacterium, the viral DNA can be included in the bacterial genome.  This way, when the bacteria reproduces that viral DNA is also reproduced along with the bacteria's own original DNA.


Sources:
The pictures and information for transformation are taken from this site: http://www.dnalc.org/view/15916-DNA-transformation.html.
The information for the transduction is from Campbell and Reece's Biology, Sixth Edition.  The picture for transduction is from: http://bacteriakingdoms.com/transduction-bacteria/.

Anatomy and Physiology: Art and Anatomy

Joseph Nollekens' Minerva.  (This picture was taken from: http://www.all-art.org/Architecture/21-2.htm.)

Ancient Greece and Rome:  The art pieces from the time during ancient Greece and Rome looked perfect.  An example is the sculpture Minerva by Joseph Nollekens.  The body is portrayed in perfection; the people were beautiful, and the features of the face were beautiful.  The ancient Greeks were obsessed with perfection and this was reflected in their art, especially the paintings and sculptures of the gods and goddesses that they worshipped.

Realist painter Jean-Francois Millet's Man with a Hoe.  (This picture was taken from: http://www.paintinghere.com/painting/Man_with_a_hoe_6237.html.)

Realism: During the realist era, there was a spur in the advancement of science and the people portrayed in the art pieces became more realistic.  For example, the painting Man with a Hoe by Jean-Francois Millet, the man who is working outside looks like an actual person.  The study of anatomy allowed the artist to produce a more realistic painting with a better knowledge of the human body.  When drawing people, muscles became more defined and the proportions of the body became more correct.

AP bio: Three Beneficial Bacteria

aA microscopic view of staphlyococcus epidermidis.  (The picture was taken from this site: http://www.flickr.com/photos/ajc1/2865663672/.)

Staphlyococcus Epidermidis




This bacteria is one of the many kinds of bacteria that live on the human skin. It is the first line of defense against harmful bacteria.  Most of these bacteria live in the hair follicles and go to the outer skin layer after humans wash their hands, but there are some that already live on the outermost skin layer.  They also live in the throat's mucous membranes.

A microscopic view of Lactobacilli in the vagina.  (This picture was taken from this site: http://textbookofbacteriology.net/normalflora.html.)

Lactobacilli


These bacteria are found in the vagina soon after a female child is born.  They make the vagina acidic as they make acid from glucose that was stored.  They stay there until other bacteria live in the vagina and it is not acidic anymore.  But when a female reaches puberty, the vagina is acidic again because a lot of Lactobacilli have inhabited it.  The Lactobacilli help protect the vagina from being attacked by other harmful bacteria and microorganisms.

A microscopic view of the viridans streptococcus in the throat.  This picture was taken from this site: http://en.wikipedia.org/wiki/Streptococcus_viridans.)

Viridans Streptococcus

These bacteria is may be passed on to a baby when it is going through the mother's birth canal.  Afterwards, the Viridans streptococcus is the main microbes that inhabit the mouth and the throat.  It stay like this for the rest of the person's life.  These bacteria are beneficial as they protect the mouth and throat when harmful bacteria or microorganisms try to invade.

Source: http://www.livestrong.com/article/355815-list-of-beneficial-bacteria-for-humans/

AP bio: Factors Affecting Cell's Rate of Diffusion

(Based on the simulation on this site: http://www.mhhe.com/biosci/genbio/biolink/j_explorations/ch02expl.htm.)

When the simulation begins, the cell has a surface area of 3 and a relative diffusion rate of 1.  When I increased the villi percent of the cell surface area, there was no effect on the relative diffusion rate.  When I cell and the dimple percent of the cell surface area, there was no effect either.  However, when I increased the radius from 1X to 10X, the relative diffusion rate decreased to 0.10..  Also, when I increased the cell shape from a ratio of 1:1 to 3:1, the relative diffusion rate increased to 2.08.  Therefore, it is supported that an increase in radius means a decrease in a cell's rate of diffusion and an increase in the cell shape ratio means an increase in the cell's rate of diffusion.

AP Bio: Cellular Respiration VS Photosynthesis

A simplified version of the process of photosynthesis.  (This picture was taken from this site:  http://mrskingsbioweb.com/Biology.html.)

Photosynthesis
6CO₂ + 6H₂O + energy -> 6O₂+ C₆H₁₂O₆
Photosynthesis is the process that converts the energy from sunlight to the glucose, which is stored as organic molecules.  This is a process that takes place inside photosynthetic organisms.  These autotrophs, or self-feeding organisms, use the process to convert light energy/sunlight into glucose (sugar) to use for food/energy.  The process of photosynthesis includes the light dependent reactions, the Calvin Cycle (dark reactions), and the electron transport chain (ETC).  The light dependent reactions and the ETC (the first part of photosynthesis) occurs in the thylakoid membranes, water and light is absorbed.  NADPH provides the energy for the reaction to occur.  Oxygen, ATP, and NADPH is produced.  In the second part of photosynthesis (the Calvin cycle), ATP, NADPH, and CO2 is used to produce sugars and NADP+.  Th NADP+ is reused in the light dependent reactions.

A simplified version of the process of cellular respiration.  (This picture was taken from this site: http://www.hyperbaric-oxygen-info.com/aerobic-cellular-respiration.html.)

Cellular Respiration
6O₂ + C₆H₁₂O₆ --> 6H₂O + 6CO₂ + energy
Unlike photosynthesis, cellular respiration converts the stored organic molecules of glucose into energy.  It includes glycolysis, the Krebs Cycle, and the electron transport chain (ETC).  in glycolysis, the reactants are glucose and the products are some ATP electrons and pyruvic acid.  This occurs in teh cell's cytoplasm.  The pyruvic acid is sent to the mitochondria, where it goes through the Kerbs cycle.  More ATP is formed, and electrons carried the NADH and FADH2 are sent to the ETC.  The ETC is in a mitochondrial membrane and has a mechanism called chemiosmosis.  At the end of the ETC, a hydrogen gradient is created by proton-motive force as the hydrogen ions move across the mitochondrial membrane into the cell and a phosphate is added to adenine diphosphate to produce adenine triphosphate (ATP).  ATP provides for most of the energy used by the cell.


Source: Campbell and Reece's Biology, Sixth Edition

Anatomy and Physiology: Skull and Bone Differences Based on Gender and Race

male and female skull differences (this picture was taken from: http://squinting-at-bones.blogspot.com/2011_07_01_archive.html)

Gender
Male skulls have a robust occipital protuberance, larger and more downward protruding mastoid process, zygomatic ridge extends beyond external auditory meatus, larger more distinct temporal line, and pronounced superciliary arches.

Female Skulls have vertical and rounded frontal, zygomatic doesn't extend beyond external auditory meatus, smaller less downward projecting mastoid process, and parietal bossing.

Race

Caucasoids skulls have narrow pointed mastoid process, rounded/elongated oval sagittal outline, small degree of facial prognathism, high and peaked nasal cross section, and a projecting chin.

American Black skulls have oblique mastoid process, high degree of facial prognathism, low and broad nasal cross section, and a elongated sagittal outline.

Asian skulls have a flatter frontal lobe, low degree of facial prognathism, a small and low nasal cross section, a less projecting chin, and a more rounded mastoid process.