Sunday, August 23, 2009

Lab Bench activity

The purpose of this lab was to learn how to calculate the net productivity, the gross productivity, and respiration.
3 ways to measure the primary productivity are:
  1. The amount of Carbon dioxide used.
  2. The rate of sugar formation.
  3. The rate of oxygen production.

Some of the factors that affect the amount of oxygen dissolved in water are:

  1. Temperture: as water becomes warmer, its ability to hold oxygen decreases.
  2. Photosynthetic activity: in bright light, aquatic plants are able to produce more oxygen.
  3. Decomposition activity: as organic material decays microbial processes consume oxygen.
  4. Mixing & Turbulence: wave action, waterfalls, and rapids all aerate water and increase the oxygen concentration.
  5. Salinity: as water becomes more salty, its ability to hold oxygen decreases.

Thursday, August 20, 2009

Define mutualism, parasitism and commensalism and give examples of each.







Mutualism- is a biological interaction between two organisms. Also in which one species benefits at the expense of the other.
Example: A clownfish and coral reefs. The clownfish benefit by having a protected home territory. But what does the anemoone gain from this?
Parasitism- a type of symbiotic relationship between 2 different organisms where one organism, the parasite, benefits at the expense of the host. In general the parasites are much smaller that their hosts.
Example: In mosquitos a female ingest blood for the protein. Male mosquitos ingest plant juices.
Commensalism- a type of relationship between 2 organisms in which one organism benefits and the other is unaffected.
Example: Barnacles getting attached to the skin of a whale or shell of a mollusk, the barnacle benefits by finding a home where nutrients are available, but the whale or mollusk shell isnt affected.

Explain natural selection and give at least 2 examples.


Natural selection- the process by which heritable traits that make it more likely to survive and reproduce becomes more common in a population over generations, it is a key mechanism of evolution.

Example: the peppered moth exists in both light and dark colors in the United Kingdom, but during the industrial revolution a lot of the trees in which the moths rested became blackened by soot which gave the dark-colored moths an advantage in hiding from predators, which means the dark-colored moths had a better chance at surviving and producing more dark-colored moths. Another example is there are some green beetles and some brown beetles, the green beetles tend to get eaten faster than the brown ones, the brown beetles reproduce more than the green beetles.

Wednesday, August 19, 2009

The human body systems & other body systems each interacts with.





















































































Integumentary system- is the organ system that protects the body from damage. In humans the integumentary system also provides vitamin D synthesis. The integumentary system is also the largest organ system.

Muscular system- is an anatomical system of species that allows it to move. In vertabrates the muscular system is controlled by the nervous system, some muscles like the cardiac muscle can be completely autonomous. 3 different types of muscles: the skeletal muscles, the cardiac/hear muscles, & smooth muscles. The muscles provide strength, balance posture, movement and heat for the body to keep warm.

Skeletal system- provides the shape and form of our bodies in addition to supporting, protecting, allowing bodily movement, making blood for the body, & storing minerals. It has 206 bones to which softer tissues & organs of the body are attached. The vital organs are protected by the skeletal system. The brain is protected by the skull and the heart and lungs are protected by the sternum and rib cage. The skeletal system interacts with the muscular system.

Circulatory system- it passes nutrients, gases, hormones, blood cells, nitrogen waste product, etc. to and from cells in the body. Humans and vertabrates, have a closed cardiovascular system, but some invertabrate groups have an open cardiovascular system. The main parts of this system are the heart, blood, and blood vessels. The digestive system works with the circulatory system to provide the nutrients needed to keep the heart pumping. The cardiovascular system & the lymphatic system collectively make up the circulatory system.

Digestive system- is made up of the digestive tract, which is a series of organs joined in a long, twisting tube from the mouth to the anus and to other organs which help the body absorb and break down food. The organs that make up the digestive tract are: the mouth, esophagus, stomach, small intestine, large intestine(colon), rectum, and the anus. Some parts of the nervous and circulatory systems, and the smooth muscle play major roles in the digestive system.

Nervous system- its a network of specialized cells that communicate information about organisms surroundings and itself, it processes the information and causes reactions in other parts of the body. It is made up of neurons and other specialized cells called glial cells(plural for glia) which aid in the fuction of the neurons. The nervous system is divided into two systems: the peripheral nervous system and the central nervous system.

Endocrine system- is a system of glands that involve the release of extracellular signaling molecules known as hormones. This system is instrumental in regulating metabolism, growth, development and puberty, and tissue function and it also plays a part in determining mood.

Reproductive system- is a system of organs inside an organism, that works together for the purpose of reproduction. Fluids, hormones, and pheromones are important accessories to the reproductive system. Major organs in the human reproductive system are the external genitalia also the internal organs, the gamete which produces gonads.

Respiratory system- function is to allow gas exchange. The respiratory system has airways, lungs, and the respiratory muscles.

Excretory system(including the urinary)- this is a system of organs that removes waste products from the body. The kidneys are considered the main excretory organs in humans. The waste leaves the body in form of urine. Other systems involved in the excretory system are the respiratory system, the digestive system, and the skin(removing waste as sweat).

Immune/lymphatic system- is a part of our general body defenses against disease. It functions by recognizing bacteria and viruses and converting the information into hormones which activate the immune process. The immune system has been broken down into different "lines of defenses" which are the: mechanical barriers, chemical barriers, phagocytosis, natural killer cells, inflammation, and fever. The function of the lymph system is to remove exess tissue fluids that dont return through the circulatory system. It is also responsible for absorbing protein form this fluid and returning it to the blood.

































Monday, August 17, 2009

3 domains of life and the kingdoms found in each.


1. Bacteria- Most known prokaryotes.


Kingdoms are: Archaebacteria & Eubacteria


2. Archae- Prokaryotes in extreme environments


Kingdoms are: Crenarchaeota: Thermophiles


Euryarchaeota: Methanogens & Halophiles


Korarchaeota: Some hot springs microbes


3. Eukarya- Eukaryotic cells


Kingdoms are: Protista(protactista), fungi, plantae, & animalia.

Describe Incomplete Dominance & give an example.


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.


An example of incomplete dominance is cross-pollination between red and white snapdragon plants, the result is the pink offspring. The dominant allele produces the red color in not completely expressed over the recessive allele that produces the white color.http://biology.about.com/od/geneticsglossary/g/incompletedom.htm

Compare & Contrast Genotype & Phenotype.



  • Genotype describes the actual set of genes.

  • Phenotype is the observable expression of characters and the traits coded for by those genes.

  • Genotype includes all alleles carried by that individual.

Saturday, August 15, 2009

Compare & Contrast Autosomes & Sex chromosomes.



Human chromosomes
Female (XX)
Male (XY)


The are two copies of each autosome (chromosomes 1-22) in both females and males. The sex chromosomes are different: there are two copies of the X chromosome in females, but males have a single X chromosome and a Y chromosome.




  • Autosomeis a chromosome that isnt a sex shromosome.

  • There are 22 pairs of autosomes.

  • X & Y chromosomes are sex chromosomes(there are 2 sex chromosomes)

Friday, August 14, 2009

Explain how an allele is different from a gene and the relationship between the two.




Genes contain information about specific characteristics/traits which can either be dominant/recessive.




Not all copies of genes are identical an alternative form of a gene is an allele.




Alleles are a way of finding the 2 members of a gene pair.




The allele of a gene is its partner gene.


For example: b is an allele of B and vise versa.




So alleles are pretty much a different form of genes.


Wednesday, August 12, 2009

Compare & Contrast Transcription in Eukaryotes & Prokaryotes.




Contrast




  • A lot of the pioneering work on transcription was carried out in prokaryotes, most notably in the bacteria E. Coli.


  • Prokaryotes have a single RNA polymerase.


  • Eukaryotes have 3 different RNA polymerase.


  • Transcription in eukaryotes is more complex.


  • Eukaryotic RNA polymerase cannot initiate transcription by themselves, they need the help of a set of proteins called the basic transcription factors.


Compare





  • The enzyme that carries out transcription is called RNA polymerase, it consist of 4 polypeptides.


  • Transcription can be divided into 3 phases: initiation, elongation, and termination.

Describe the process of Translation.


Translation is the first stage of protein biosynthesis(part of overall process of gene expression.) Translation happens in the cytoplasm where the ribosomes are located. During translation mRNA(messenger RNA) is decoded to make a specific polypeptide. Translation happens is 4 phases: activation, initiation, elongation and termination.

Describe the process of transcription in eukaryotic cells.


Its primarily located in the nucleus, where it gets separated from the cytoplasm(in which translation occurs) near the nucleur membrane. DNA is also in the mitochondria in the cytoplasm and the mitochondria utilize a special RNA polymerase for transcription. The basal eukaryotic transcription includes: RNA polymerase and additional proteins that are necessary for the correct initiation and elogation.

TRANSCRIPTION PROCESS


Name
transcribed
RNA Polymerase I (Pol I, Pol A)
nucleolus
Larger ribosomal RNA (rRNA) (28S, 18S, 5.8S)
RNA Polymerase II (Pol II, Pol B)
nucleus
messenger RNA (mRNA) and most small nuclear RNAs (snRNAs)
RNA Polymerase III (Pol III, Pol C)
nucleus (and possibly the nucleolus-nucleoplasm interface)
transfer RNA (tRNA) and other small RNAs (including the small 5S rRNA)http://en.wikipedia.org/wiki/Eukaryotic_transcription

Monday, August 10, 2009

Compare and contrast mitosis and meiosis.




Meiosis is a form of cell division that produces gametes in humans these are egg cells and sperms, each with reduced or halved number of chromosomes.




A cell with 2 copies is called a diploid cell with 1 copy is called a haploid cell.




Meiosis produces haploid daughter cells which are genetically different from each other and the parent cell.




Mitosis is the form of cell division that produces daughter cells identical to the parent cell.


Add Image


Meiosis has 2 divisions, while Mitosis has 1 division.




But both divisions have the stages:




  • interphase


  • prophase


  • metaphase


  • anaphase


  • and telophase






Compare & Contrast mitosis & binary fission.






  • Binary fission is in prokaryotic cells.


  • Mitosis is in eukaryotic cells.


  • Binary fission is a form of asexual reproduction.


Mitosis is the process in which a eukaryotic cell separates the chromosomes in its cell nucleus int 2 identical sets in 2 daughter nuclei.



Binary Fission is the form of asexual reproduction and cell division used by all prokaryotic and some eukaryotic organisms.

Compare & Contrast catabolic & anabolic reactions & add the definition of both.


Catabolic: Relating to or characterized by catabolism, or characterized by destructive metabolism.http://wordwebnet.princeton.edu/perl/webwn


Anabolic: Of or related to the synthetic phase of metabolism, or characterized by or promoting constructive metabolism. " Some athletes take anabolic steroids to increase muscle size temporarily".http://wordnetweb.princeton.edu/perl/webwn


Contrast



  • Catabolic reactions release energy that is used to drive chemical reactions.

  • Anabolic reactions usually require energy.

  • The energy of catabolic reactions is used to drive anabolic reactions.