Saturday, January 21, 2012

AP Bio: Three Key Ideas in Time, Love, Memory

Time
The concept of time is discussed mainly in Chapter 8: First Time.  It talked about how the flies in the experiment had a sense of time.  Konopka experimented with this in Benzer's laboratory and eventually discovered a gene that they called the "clock gene." It was the gene that controlled the flies' sense of time.  The flies had a routine of being active at sunup and stop moving at sundown, even if the room they were in was dark.  Without the gene, they did not follow this routine and would "wake and sleep at random intervals" (5).


Love
The concept of love is discusses mainly in Chapter 9: First Love.  It begins with the quote by William Blake, from "The Question Answer'd": "What is it men in women do require?  The lineaments of Gratified Desire.  What is it women in men do require?  The lineaments of Gratified Desire" (112).  The book goes on to explain that according to Darwin, reproduction is an important part in adaptation of survival.  It gives the chance for the more favorable genes to be expressed.  In the experiment in the book, flies have certain steps in their mating process.  They discovered that this chain of steps is controlled by a gene.  In other words, every step in the mating process is inherited.


Memory
The concept of memory is discussed mainly in Chapter 10: First Memory.  The book talks about how "evolution is learning" (132) and that "species store learning in chromosomes the way individuals store learning in their brains and societies store learning in books."  There is information that the flies would learn at the present time and the information that their ancestors had when life began.  The ability to learn and remember is also in their genes, for "the memory of discovery...has been passed down from generation to generation since near the beginning of life" (132).


Source: Time, Love, Memory: A Great Biologist and His Quest for the Origins of Behavior by Jonathan Weiner

Anatomy and Physiology: Lesson from Dead Men Do Tell Tales

The skeleton of Joseph Merrick the Elephant Man, a haunting image.  This picture was from: http://www.thebalde.net/edukia.php?uuid=152&lang=en.




After reading Dead Men Do Tell Tales, I learned that bones could tell a lot about the life of a person: the diseases they had, the injuries they sustained, how they died. . .
Because of this, bones could be very useful in solving murder cases or convicting a wanted criminal, as seen in the many cases that the author, William R. Maples, P.H.D., helped solve.
I would not be a forensic anthropologist because I feel that there is something very haunting and ghostly in looking at someone's remains who used to be a real, live person just like me.

AP Bio: Major Plant Divisions



Charophyceans
These are green algae most closely related to land plants.  Like land plants, they have the pigments beta carotene, chlorophyll b, and accessory pigments.  They have cell walls (made of cellulose), perixisomes, and stacks of thylakoids (called grana).

Hornworts, from the bryophyte division


Bryophytes
Bryophytes are made of the three phla liverworts, hornworts, and mosses.  These plants are not true vascular plants.  However, they have special tissues that transport water and nutrients.  Because they don't have lingin in their structures, they are shorter and weaker than other plants.  For their reproductive structures, they are enclosed and are called sporangia and gametangia.  Instead of reproducing through flowers and seeds, bryphytes reproduce by using spores.

Horsetails, from the pteridophyte division


Pteridophytes
These include ferns, club mosses, spike mosses, and horsetails.  They are true vascular plants and have xylem and phloem, and stems, roots, and leaves.  Most of them have true roots that have lignified vascular tissue.  They are seedless and don't reproduce through flower, but reproduce through spores.

A ginkgo tree, from the gymnosperm division.


Gymnosperms
These plants have seeds and examples include.  confiers, ginkgo, and caycads.  Unlike angiosperms (whose seeds/ovules are enclosed during pollination), their seeds are "naked," meaning they are not enclosed.  When the seeds are unfertilized, they are called ovules.  Their seeds develop on the end of short stalks or on cones.



Angiosperms
Although angiosperms produce seeds like gymnosperms, they are also are flowering plants and their seeds are enclosed.  The flowers act as the reproductive organs of these kinds of plants.  During pollination, pollen is transferred from the anthers of one flower to the stigma of another flower, allowing for fertilization and sexual reproduction.

Source:
The charophycean picture is from: http://www.thaigoodview.com/node/48439.

Anatomy and Physiology: Three Factors that Affect Heart Rate

This picture was from: http://www.zeitnews.org/applied-sciences/tiny-new-tool-to-track-heart-rate-in-real-time-on-a-smartphone.html.




During a lab this week, we experimented with factors that can change heart rate.  Three examples of these factors were caffeine, sugar, and music.  Caffeine, sugar, and fast music increased my heart rate while slow music slowed down my heart rate.







These factors can affect other systems.  Caffeine can take toll on the nervous system if too much of it is consumed.  Sugar can affect the endocrine system because when there is sugar in the bloodstream, the pancreas will secrete more of the hormone insulin into the bloodstream.  Music can affect the immune system.  Listening to, in particular, slow, relaxing music can reduce stress lower high blood pressure, boosting the immune system.


Source:
The information about music came from: http://www.livestrong.com/article/135181-music-its-effects-heart-rate/.
The picture of coffee was from: http://www.kobos.com/Kobos_Knows/Kobos-Knows-Coffee/Caffeine/.
The picture of sugar was from: http://www.angrytrainerfitness.com/2011/04/ask-alfonso-simple-sugars-the-simple-truth/.
The picture of music notes was from: http://www.hoopcity.ca/page/hooping-music.

AP Bio: Article 4 - A Fear of Pheromones




This article began by presenting the idea of humans using odors to communicate.  These odors, called pheromones, are used by many animals to communicate.  Examples that were given included the female moth's bombykol, a catfish recognizing the smell of a leader, and a bullhead identifying which way his rival was swimming.




However, humans do not use pheromones to communicate; instead we use things like the telephone, notes, invitations, and letters.  Recently, there have been studies done on why humans do not communicate with pheromones.  So far, it is shown that humans have the potential to do so, (such as schizophrenic patients having a certain odor in their sweat), and these kinds of studies continue as scientists try to find the answer to this question.


Sources:
The moth picture is from: http://www.itsnature.org/air/creepy-crawlies-air/bogong-moth/.
The catfish picture is from: http://www.starfish.ch/collection/benthicfishes.html.

AP Bio: Article 3 - On Societies as Organisms

A close up of an ant colony.  (This picture is from: http://www.aacutepestcontrol.com/carpenter_ant_pictures.htm.)




Again, this article is based on the idea that the world is one organism.  The author compares human society to an ant colony.  Just as the existence of a single ant is meaningless until it is seen in the light of the whole ant colony, humans are most interconnected when they work together to make society work.  He also mentions that it is ironic that although humans are considered the most social animals,  "we do not often feel our conjoined intelligence."  However, he goes on to explain that maybe people are connected with each other in the way we process information and that "it may be [that] our biological function [is to] build a certain kind of Hill" that is different from the kind of community that is seen among other animals.

AP Bio: Article 2 - Thoughts for a Countdown

In another article, the author of "The Lives of a Cell," starts out by describing the decontamination process that astronauts who came back from the moon go through.  It is feared that they brought back some kind of harmful microbes or life-forms.  However, he goes on to say that although people tend to have a fear to these microbes, "most of the associations between the living things we know about are essentially cooperative ones."  Again, he emphasizes that each living thing is dependent on each other, and this includes microbes.  He also write that organisms such as bacteria and fungi serve as models that the biologists could study because they have relationships that are similar to the social interactions between animals.  Bacteria have symbiotic relationships with insects when they live in their tissues as do anemones and fishes.

AP bio: Article 1 - The Lives of a Cell

An image of Earth from space.  The author of "The Lives of a Cell" concludes his first article with the proposition that Earth is just one giant organism.  (This picture is from: http://www.solstation.com/life/ear-life.htm.)




In this article, the author begins with the image of "Modern Man." He is looking down at the world, as if he is superior to it, but the author goes on to explain that "it is illusion to think that there is anything fragile about the life of the earth..." and that "we are the delicate part..." of it.  Humans depend on nature and the two are more related than we would think.  An example that the author gives are the mitochondria inside our cells.  They used to be free-living beings, but through endosymbiosis, were taken into cells.  The cell gives the mitochondria an environment to live in and the mitochondria play a large role in providing our cells, and therefore, us with energy.  The author ends the article with proposing the idea that the world "is most like a single cell."

Anatomy and Physiology: Exercise Benefit

(This picture was taken from: http://www.metrolic.com/american-diet-2816/.)




Based on this week's labs (muscle fatigue/exercise heart rate), it is harder for a fit person to get exercise benefit because it will take more for them to reach their limit.  A person who is not as fit can exercise less or exercise less rigorously and get more exercise benefit, it is easier for them to build up their muscles or their energy.  Only when a person's muscles is pushed a little beyond their limit, it will train them to take more.  A less fit person can do less to get exercise benefit while a fit person needs to do more to get the same amount of exercise benefit.

AP bio: Most Surprising Thing in Time, Love, Memory So Far

(This picture is from: http://books.google.com/books/about/Time_love_memory.html?id=I0a5AjpKwrEC.)


In Jonathan Weiner's Time, Love, Memory: A Great Biologist and His Quest for the Origins of Behavior, flies are used to experiment on to study the inheritance of genes and what controls behavior.

(This picture was from: http://amazingdata.com/insects-of-our-world-up-close-and-personal/.)


The most surprising thing was the flies' ability to survive.  In one part of the experiment, they cut off a fly's head to observe the effect on its behavior.  The result was that it learned faster to avoid certain objects/things that would cause pain than a fly whose head wasn't cut off.  The fly whose head was cut off lived for two weeks or so before it died.  We certainly can't live for that long if our heads were decapitated!

Anatomy and Physiology: Most Interesting Thing in Dead Men Do Tell Tales So Far

The part in Dead Men Do Tell Tales that has interested me the most so far is whenever Maples uses bones to convict murderers.  It is amazing what stories that the bones could tell you if you know how to look at them correctly.  One of the many murder cases that he helped clear up was one where a man named Raymond Stone murdered the wife of the farmer that hired him.  When her body was found, it had been torn apart by alligators.  Her skull was found later and Maples found a head wound that was inflicted by a hatchet in such a way that the least blood possible will be spilled.  After an investigation into Stone's background and records, it turns out that he killed the farmer's wife when she refused his advances.  Stone was convicted and sentenced to jail.  And with just one bone, Maples was able to bring a criminal to justice.

Anatomy and Physiology: Chapter 5 Wordle

link to chapter 5 wordle: http://www.wordle.net/show/wrdl/4711228/Untitled

I made the word skeletal system the biggest, as the chapter centers around the skeletal system.  It is divided into two parts, the axial skeleton and appendicular skeleton, which are the next biggest words.  The two types of bone tissue are compact bone and spongy bone (where the marrow and red blood cells are formed.)  Bones can be classified either as long bones, short bones, flat bones, or irregular bones depending on their shape.  The structure of the long bone includes the diaphysis/shaft, the epiphyses (ends of the bones.)  Bone cells can be osteocytes, osteoblasts, or osteoclasts.  Osteocytes are mature bone cells, osteoblasts are bone-forming cells, and osteoclasts are bone-destroying cells.  Osteoblasts play a role in ossification/bone formation and bone remodeling (healing of a bone fracture).  Osteoclasts break down old tissue.

Source: Elaine N. Marieb's Essentials of Human Anatomy & Physiology, Eighth Edition

AP bio: Diversity of Cells Wordle

link to the diversity of cells wordle: http://www.wordle.net/show/wrdl/4711167/Untitled


Bacteria, virus, fungi, and protozoan were the main topics of this unit.  Bacteria can reproduce through transduction, transformation, and conjugation.  Viruses replicate with the lytic and lysogenic cycles.  Fungi have different phyla with chytrids, zygomycetes, ascomycetes, or basidiomycetes.  Protozoans are believed to have arose through serial endosymbyosis and adapt to the environment with alternations of generations, and can move with pseudopodia or cellular slime molds.  Bacteria, virus, fungi, and some protozoans can cause disease.  Viroids and prions do not fall into these categories but can also become diseasing agents.


Source: Campbell and Reece's Biology, Sixth Edition

AP bio: Cellular Metabolism (Chapter 6) Wordle

link to cellular metabolism wordle: http://www.wordle.net/show/wrdl/4710967/Untitled


I chose to make cellular respiration and photosynthesis the biggest words because they are the metabolic processes that were discussed.  I made the redox reactions the next biggest because it describes how cellular respiration and photosynthesis involve transferring electrons from a reactant to another.  It is followed by the different parts of the cellular respiration: glycolysis, Krebs cycle, and the electron transport chain (ETC); and the different parts of photosynthesis: light dependent reaction and Calvin cycle/dark cycle/light independent reactions.  I also included main structures that are involved in these reactions, such as chlorophyll and photosystem.  Some processes that drive cellular respiration and photosynthesis is oxidative phophorylation, chemiosmosis, noncycle photophosphorylation, and cyclic photophosphorylation.  For cellular respiration, depending on whether it is anaerobic or aerobic process (whether there is oxygen or not), there are alternative pathways to release energy, such as alcohol fermentation or lactic acid fermentation.


Source: Campbell and Reece's Biology, Sixth Edition

AP bio: Phyla of Protozoa

A microscopic view of a amoeba, a protist from the phylum Sarcomastigophora.  This picture was from: http://homosapienssaveyourearth.blogspot.com/2012/01/it-2-01-amoebas-heavenly-dream.html.)




Phylum Sarcomastigophora
The protozoa in this phyla can be unicellular or colonial.  They can move around by flagella, pseudopodia, or both, and usually reproduce through binary fission and sexual reproduction.  An example of a protozoa from this phylum include the amoeba, which uses a psueopod or "fake foot" to move around.


A microscopic view of the parasitic protozoan labyrinthuloides haliotidis, which is from the phylum labryinthormorpha.  This picture is from: http://eol.org/pages/21984/overview.)




Phylum Labryinthormorpha
The protists in this phylum are spindle-shaped or spherical.  They move by gliding on mucous.  Most of these protozoans are marine and are parasitic towards algae.  An example is labyrinthuloides haliotidis, which is a parasite for abalone.

A microscopic view of mature Plasmodium-malariae.  This picture is from: http://en.wikipedia.org/wiki/Plasmodium_malariae.


Phylum Apicomplexa
These protozoans have a stage in their life cycle where they produce spores.  They have a unique structure called the apical complex (a arrangement of vacuoles, fibers, and other organelles at one end of the cell).  They have complex life cycle in which they inhabit two hosts (ex: a mammal and a mosquito).  The life cycle has an alternation of generations of haploid and diploid and they can reproduce asexually or sexually.  At some point in life, they produce a lot of small infectious organisms through a process called schizogony.  An example of this kind of protozoan include the pathogen Plasmodium-malariae.


This shows a host cell that is infected by Brachiola algerae, a protozoan from the phylum microspora.  This picture is from: http://www.cns.fr/spip/Brachiola-algerae-a-multi-host.html.


Phylum Microspora
These protozoans are intracellular parasites.  They do not have mitochondria and some are pathogens of insects, and are transmitted by a spore.  Five kinds have been seen in the implications of human diseases, such as in people with AIDS.  An example is the Brachiola algerae, which is a pathogen transmitted by mosquitoes. 


A microscopic view of Bonamia ostreae infecting oysters.  This picture is from: http://www.scotland.gov.uk/Topics/marine/Fish-Shellfish/18364/18610/diseases/notifiableDisease/Bonamiaostreae.




Phylum Ascetospora
These protozoans are parasitic protists.  They have spores for reproduction and do not have polar filaments or polar caps, and are parasitic in mollusks.  An example is the Bonamia ostreae, which infects the flat oyster Ostrea edulis (a type of mollusk).  



The spores of Kudoa thyrsites, a parasitic protist from the phylum Myxozoa.  This picture is from: http://www.journalofparasitology.org/doi/abs/10.1645/GE-548R.1.)




Phylum Myxozoa
These protozoans are also parasitic protists.  Like the phylum Ascetospora, they also have resistant spores.  The spres have one to six polar filaments and these protists are parasitic in fish, both freshwater and marine.  They can cause economic problems in salmon that the farmed.  An example is kudoa thyrsites, which attacks fish muscle and loosens it.


A microscopic view of Paramecium caudatum, a protist from the phylum Ciliophora.  This picture is from: http://101science.com/paramecium.htm.)




Phylum Ciliophora
Phylum Ciliophora is the largest out of the phyla of protozoa.  These protozoans are characterized by using cilia to move around.  They have various unique structures, such as tentacles or toxicysts (threadlike darts).  To feed, they capture food with the cilia and the food is eventually passed to the vacuoles to digest.  These protozoans can reproduce asexually by binary fission and sexually by conjugation.  Most of them are harmless but some are parasites.  An example is the Paramecium caudatum, a harmless, free-living protist. 


Sources:
http://highered.mcgraw-hill.com/sites/0072320419/student_view0/chapter27/study_outline.html
Campbell and Reece's Biology, Sixth Edition

AP bio: Comparing Bacteria, Virus, Prion, and Protist

A typhoid bacterium.  (This picture is from: http://news.softpedia.com/news/Typhoid-Bacterium-Accompanied-Us-Along-Our-Evolution-41046.shtml.)


Bacteria
Bacteria can adapt very well to environment that change constantly because they have short generation spans.  During these short generation spans, they can undergo genetic recombination.  This way, so when they reproduce through various ways such as transformation, transduction, and conjugation, the new DNA will replicate along with their own original DNA.  These new, foreign DNA are expressed in the new strains of transformed bacteria.  This also lets each bacterium adapt their metabolic processes with the changes of their environment.

A diagram of the structure of a vius.  (This picture was from: http://www.armageddononline.org/viruses.html.)


Virus
Unlike bacteria, virus are not actually alive because they cannot survive outside a host.  They are basically just genes in a protective coat.  The parts of a virus includes its capsid, protein coat, viral envelope, and nucleic acid.  Bacteriophages are the group of viruses that can infect bacteria.  They reproduce through the lytic and lysogenic cycles.  In the lytic cycle, they attack the host cell and when the cell bursts, the new viruses move on to destroy other host cells.  In the lysogenic cycle, the virus may lie in wait in the host cell for a long time before the lytic cycle is activated and it destroys the host cell.

The structure of a prion.  (This picture was from: http://www.physorg.com/news153681509.html.)


Prion
Prions are simple infectious agents.  They are basically protein that are misfolded.  It has no genetic material.  Although they are proteins, they can reproduce on their own and become infectious agents.  In humans, they may have been linked with the Creutzfeldt-Jakob Disease (CJD) and the Gerstmann-Straussler-Scheinker Syndrome.

A microscopic view of a paramecium, a protist.  (This picture was from: http://www.mlms.loganschools.org/~ckircalli/homework/MATH_SCIENCE%20LINK%20PAGES/PROTIST%20INTERNET%20LESSON.html.)


Protist
Protists are eukaryotic microoorganisms.  They are classified in the Protista kingdom, which also includes unicellular organisms.  Sometimes, their behavior might make them pathogens that infect plants and animals.  Protists have a lot of different ways of feeding, such as filter feeding in flagellates and endocytosis (usually phagocytosis or cell-eating, but sometime pinocytosis or cell-drinking.)  Some reproduce sexually with gametes or asexually through binary fission.  Other protists are more complicated and have life cycles in which some forms of the organism reproduce sexually and others asexually.

Anatomy and Physiology: Mink and Human Muscle Similarities

(This picture was from: http://uscunion.sc.edu/biology/Dissections/MinkMuscArm2L.jpg.)
Note the similarities in the structure of the mink and human arm muscles.  (This picture was from: http://anatomyeshs.wikispaces.com/Ch.8+Muscular+System.)




During the mink dissection, I saw that many of the muscles on the mink had the same shapes as their human counterparts.  For example, when we identified some of the muscles in the leg, the mink had the muscles biceps femoris, sartorius, gastrocnemius, adductor longus and femoris, semitendinosus, etc.  All of these muscles are in the human leg.  They are also similar in shape.  For instance, the biceps femoris in the mink and the human are pennate muscles, or muscle that attaches at a oblique angle to its tendon.  The thing that surprised me most about the mink was the numerous similarities in muscle structure and function.  It reminded me of the evidence that was used by evolutionists to back up Charles Darwin's theory of evolution; one of the evidence was similarities in bone and muscle structure.

Anatomy and Physiology: Mink and Human Muscle Shapes

The biceps brachii is an example of a fusiform muscle.  It is wider in the middle and tapers at the ends.  (This picture was from: http://athleticconditioning.blogspot.com/2010/05/building-bigger-biceps.html.)


Fusiform:
Fusiform muscles are spindle-shaped.  Examples include many of the arm muscles, such as the biceps brachii, flexor carpi radialis, extensor radialis longus, and brachioradialis.


Location of the quadratus femoris, a quadrate -shaped muscle.  (This picture was from: http://medicina.ronnie.cz/c-1451-svaly-kycelniho-kloubu.html.)




Quadrate:
Quadrate muscles are quadrilateral-shaped.  Examples include the pronator quadratus on the distal forearm and the quadratus femoris on the thigh.


Location of the external oblique muscle, a flat muscle with aponeurosis.  (This picture was from: http://www.weight4me.com/fitness/muscles/external_oblique.htm.)




Flat with Aponeurosis:
These muscles have layers of flat, broad tendons.  Examples include abdominal muscles, such as the external oblique muscle and the internal oblique muscle.


Location of the extensor digitorum longus, a unipennate muscle, in relation to the muscle around it.  (This picture was from: http://www.getbodysmart.com/ap/muscularsystem/footmuscles/menu/menu.html.)




Unipennate:
Unipennate muscles have muscle fibers that stretch in the same direction.  Examples include the extensor digitorum longus and the brachialis.


Location of the rectus femoris in relation to the other muscles on the femur.  (This picture was from: http://www.t-nation.com/free_online_article/sports_body_training_performance_repair/18_tips_for_bulletproof_knees.)




Bipennate:
Bipennate muscles have two rows of muscle fibers that stretch in opposite directions and have a central tendon.  Examples include the rectus femoris and the gastrocnemius.


Location of the deltoid muscles.  (This picture was from: http://www.sciencelearn.org.nz/Contexts/Sporting-Edge/Sci-Media/Images/Deltoid-muscles.)




Multipennate:
Multipennate muscles have more than two rows of muscle fibers that stretch in different directions and have a central tendon that branch off into two or more tendons.  Examples include the deltoid muscle and the pectoralis major muscle.


Source:
The list of muscle shapes was taken from this site: http://www.netterimages.com/image/7453.htm.)

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.