1. The main defender is Rick O'Barry
3. Rick O'Barry became involved in saving dolphins when one of his dolphins, Kathy committed suicide.
5. Dolphins are in the mammalian order of cetacean.
7. Small islands in the Caribbean support whaling because the Japanese government pays them.
9. Some of the dolphins are stabbed to slow them down.
11. The main point of this move is to expose the dolphining in Taiji, which led to feeding the global population high concentrations of mercury, and pushing the dolphin population closer and closer to extinction.
13. Biomagnification: toxins present in an organism gets magnified as it moves up the food chain. At the top of the food chain, the concentration of toxins has been greatly magnified.
15. They refuse the offer because the government tells them it's "pest control" (the government tells them that the dolphins are eating too much of the fish they actually want to catch).
17. They disguise cameras by making them look like the rocks found near the cove.
19. The crew member puts the video captured of the fishermen killing the dolphins on a portable screen and walk into the meeting wearing the screen so everyone could see how dolphins were really killed.
21. One of the injured dolphins tries to escape, but due to its injuries, it is unable to swim and come up for water and eventually drowns and dies.
23. Although going to Marineland does not contribute to dolphin slaughter itself, it promotes dolphin capturing, which the fishermen of Taiji also do. When a dolphin is captured and trained to be a "showcase" in an animal park, it loses its freedom.
Tuesday 2 June 2015
Friday 15 May 2015
Photosynthesis vs. Cellular Respiration
Photosynthesis is the process of making glucose that will end up being used by all organisms on earth, and cellular respiration is the process of converting glucose into ATP. The chemical reaction of photosynthesis is 6H2O+ 6CO2 --[light and chlorophyll]--> C6H12O6 + 6O2 and the chemical reaction of cellular respiration is the reverse of that, only, it does not need light or chlorophyll to happen.
The two processes are similar in that they have the same substances in the beginning and end. As well, both processes are needed to ensure that cells in an organism get the ATP they need. In both processes, ATP is produced. In the light dependent reaction of photosynthesis, ATP is made during the chemiosmosis of hydrogen ions through ATP synthase. In glycolysis, Krebs cycle, and the electron transport chain of cellular respiration, ATP is produced.
In glycolysis, ATP is produced when BPG is converted into PGA (two molecules of ATP are produced, as glycolysis yields two BPGs). In the Krebs cycle, ATP is made when succinyl CoA becomes succinate (again, two ATPs are made). Finally, in the ECT, ATP is made when electrons pass through NADH dehydrogenase, coenzyme Q and cytochrome b-c1 complex, and cytochrome oxidase complex (COC).
Both cellular respiration and photosynthesis need the proton gradient across membranes to power ATP synthase, which in turn, makes ATP. As protons move through ATP synthase, it attaches another phosphate unto ADP to make 3 phosphates.
Finally, both these processes happen inside organelles with double membranes. Photosynthesis happens in chloroplasts (in plants and bacteria), and cellular respiration happens in mitochondria (all other organisms).
Photosynthesis and cellular respiration have many differences as well as similarities, but in the end, they are both very important processes living things need to obtain energy.
Thursday 14 May 2015
The Light Dependent Reaction vs The Light Independent Reaction
PHOTOSYNTHESIS (LIGHT DEPENDENT)
Photosynthesis is a process that happens in plants and bacteria that allows them to make their own energy. This process also provides energy for every other organism on earth. More specifically, it happens in the chloroplasts of plants. Chloroplasts are special cells in plants that have 2 membranes, and are made up of stacks of thylakoids (granum). The thylakoid contains chlorophyll, which is a catalyst. It is in the thylakoid where light is used to produce ATP and NADPH (energy carrying molecules).
Photosystem II absorbs light with wavelengths of 680nm, in doing that, it splits a water molecule and takes its electrons in a process called hydrolysis(leaving 2 protons and an oxygen ion). The electrons make it down the electron transport chain, leaving redox reactions in its wake.
The electrons are passed to PQ (plastoquinone), PSII oxidizes and PQ reduces. Then, from PQ, the electrons travel to B6F, and a portal is created for hydrogen ions to flow out of the thylakoid membrane. Then they are passed to PC, but before they can be passed to Photosystem I, PSI must be struck by light of 700mn.
From PSI, the electrons are passed to FD and FNR. FNR then passes them to NADP+ to make NADPH. This entire process continues as long as there is an abundant amount of both water and sunlight.
(PSII > PQ > B6F > PC > PSI > FD > FNR > NADP+ > NADPH)
The hydrogen that were transferred through PQ and B6F cause an imbalance of pH on either side of the membrane. This causes the H+ ions to go back into the chloroplast stroma through the ATP synthase, in a process called chemiosmosis. This allows ADP to be converted into ATP (by adding a third phosphate). This entire process is known as the non-cyclic light dependent reaction and it happens in eukaryotic cells.
Prokaryotes use the cyclic light dependent reaction which only consists of B6F, PSI, FD, and FNR, and electrons are returned to B6F again, and again (creating the electron portal). In this process, however, NADPH is not made, and ATP is used directly, instead of making glucose.
CALVIN CYCLE (LIGHT INDEPENDENT)
The light independent does not use energy from the light, but rather the energy from ATP (which is made from the light dependent reaction).
The Calvin Cycle begins with carbon fixation, a process where carbon dioxide reacts with RuBP (ribulose biphosphate) and produces 2 strands of PGA, each with 3 carbons, since carbon chains with more than 6 carbons are unstable. This reaction is catalyzed with rubisco.
A phosphate from ATP is added to each PGA, changing it into BPG, and the two ADPs go back to the light dependent reaction to be reconverted into ATP. Then, a phosphate group is removed from BPG by NADPH, in that process, a hydrogen from NADPH is lost, and NADP+ also goes back to the thylakoid to be reconverted into NADPH. The compounds that are formed from the loss of phosphate are G3P. The two G3Ps formed can combine (with the help of a reshaping enzyme) to make one molecule of glucose.
The results from one cycle of the Calvin cycle are as follows: 3 RuBPs catalyzed > 6 PGAs made > 6 BPGs > 6 G3Ps
5 of the 6 G3Ps are recycled through a series of reactions and becomes RuBP to go through the cycle again, and 1 of them makes it out of the cycle. Therefore, it takes two Calvin cycles to make one molecule of glucose.
OVERALL REACTION
6CO2 + 6H2O -[light and chlorophyll]-> C6H12O6 + 6O2
Photosynthesis is a process that happens in plants and bacteria that allows them to make their own energy. This process also provides energy for every other organism on earth. More specifically, it happens in the chloroplasts of plants. Chloroplasts are special cells in plants that have 2 membranes, and are made up of stacks of thylakoids (granum). The thylakoid contains chlorophyll, which is a catalyst. It is in the thylakoid where light is used to produce ATP and NADPH (energy carrying molecules).
Photosystem II absorbs light with wavelengths of 680nm, in doing that, it splits a water molecule and takes its electrons in a process called hydrolysis(leaving 2 protons and an oxygen ion). The electrons make it down the electron transport chain, leaving redox reactions in its wake.
The electrons are passed to PQ (plastoquinone), PSII oxidizes and PQ reduces. Then, from PQ, the electrons travel to B6F, and a portal is created for hydrogen ions to flow out of the thylakoid membrane. Then they are passed to PC, but before they can be passed to Photosystem I, PSI must be struck by light of 700mn.
From PSI, the electrons are passed to FD and FNR. FNR then passes them to NADP+ to make NADPH. This entire process continues as long as there is an abundant amount of both water and sunlight.
(PSII > PQ > B6F > PC > PSI > FD > FNR > NADP+ > NADPH)
The hydrogen that were transferred through PQ and B6F cause an imbalance of pH on either side of the membrane. This causes the H+ ions to go back into the chloroplast stroma through the ATP synthase, in a process called chemiosmosis. This allows ADP to be converted into ATP (by adding a third phosphate). This entire process is known as the non-cyclic light dependent reaction and it happens in eukaryotic cells.
Prokaryotes use the cyclic light dependent reaction which only consists of B6F, PSI, FD, and FNR, and electrons are returned to B6F again, and again (creating the electron portal). In this process, however, NADPH is not made, and ATP is used directly, instead of making glucose.
CALVIN CYCLE (LIGHT INDEPENDENT)
The light independent does not use energy from the light, but rather the energy from ATP (which is made from the light dependent reaction).
The Calvin Cycle begins with carbon fixation, a process where carbon dioxide reacts with RuBP (ribulose biphosphate) and produces 2 strands of PGA, each with 3 carbons, since carbon chains with more than 6 carbons are unstable. This reaction is catalyzed with rubisco.
A phosphate from ATP is added to each PGA, changing it into BPG, and the two ADPs go back to the light dependent reaction to be reconverted into ATP. Then, a phosphate group is removed from BPG by NADPH, in that process, a hydrogen from NADPH is lost, and NADP+ also goes back to the thylakoid to be reconverted into NADPH. The compounds that are formed from the loss of phosphate are G3P. The two G3Ps formed can combine (with the help of a reshaping enzyme) to make one molecule of glucose.
The results from one cycle of the Calvin cycle are as follows: 3 RuBPs catalyzed > 6 PGAs made > 6 BPGs > 6 G3Ps
5 of the 6 G3Ps are recycled through a series of reactions and becomes RuBP to go through the cycle again, and 1 of them makes it out of the cycle. Therefore, it takes two Calvin cycles to make one molecule of glucose.
OVERALL REACTION
6CO2 + 6H2O -[light and chlorophyll]-> C6H12O6 + 6O2
Sunday 3 May 2015
Pig Dissection!
On the 27th and 28th of April, a pig dissection was done in SBI 4U1-03. Each lab group received a pig.
After cutting open the pig, we first isolated the liver. The liver produces bile (a substance that breaks down fats), stores glucose as glycogen, cleanse drugs of toxins, and stores iron.
The next isolation was the stomach. It looked like a little sac, and inside contained dark particles that looked like pellets. This is likely to be a substance called meconium, which is made up of the things the infant ingested while in the uterus (eg. epithelial cells, bile, amniotic fluid). The stomach is the organ that holds the bolus (food) that an organism eats. In the stomach, the food is churned with acid to break it down.
The pancreas is a lumpy, leafy-looking organ that produces insulin and glucagon. As well, it secretes digestive juices that help further break down food in the small intestines.
Below are a pair of kidneys. Kidneys are bean-shaped organs that filters out toxins from blood, absorbs nutrients for blood, and make urine.
Another organ that comes in pairs. Our pig was female, therefore, it was necessary to isolate the ovaries. The ovaries are what contain the eggs of a female. These eggs have half the DNA of a regular cell and, with a sperm cell, can form a zygote.
The spleen is a long, thin, organ that filters blood, which helps the immune system recognize dangerous antibodies.
After the kidneys make urine, it is stored inside the bladder. The bladder is a sac that leads to the urethra, where the urine is excreted.
The heart is made of strong cardiac muscle that circulates blood throughout the body. This organ is what makes sure that all parts of the body can get what it needs (eg. oxygen, glucose) as well as can get rid of what it doesn't need (eg. carbon dioxide, waste)
Lungs bring in what every mammal needs to survive, oxygen. Not only that, it also gets rid of what could be toxic to our bodies if its concentration gets too high, carbon dioxide. This is also a body part that comes in pairs. Lungs are filled with tiny little sacs that increase surface area to get maximum oxygen.
Eyes are sensory organs that allow us to see. Light rays enter the eye lens and the information is interpreted in the brain.
The gallbladder is a small organ that holds the bile (produced by the liver) until it is needed.
Lastly, the arguably most important organ, the brain. The brain was hard to isolate, due to its delicateness, and therefore took the most time. The brain is the control centre for the entire body. It processes information, and relays an appropriate response to it. The brain controls all our conscious thoughts and all our unconscious thoughts.
 |
| The "before" of the pig. |
After cutting open the pig, we first isolated the liver. The liver produces bile (a substance that breaks down fats), stores glucose as glycogen, cleanse drugs of toxins, and stores iron.
 |
| The liver is the largest organ in the pig. |
The next isolation was the stomach. It looked like a little sac, and inside contained dark particles that looked like pellets. This is likely to be a substance called meconium, which is made up of the things the infant ingested while in the uterus (eg. epithelial cells, bile, amniotic fluid). The stomach is the organ that holds the bolus (food) that an organism eats. In the stomach, the food is churned with acid to break it down.
 |
| Stomach |
 |
| Contents of the stomach : meconium |
The pancreas is a lumpy, leafy-looking organ that produces insulin and glucagon. As well, it secretes digestive juices that help further break down food in the small intestines.
 |
| Pancreas |
Below are a pair of kidneys. Kidneys are bean-shaped organs that filters out toxins from blood, absorbs nutrients for blood, and make urine.
 |
| Kidneys |
Another organ that comes in pairs. Our pig was female, therefore, it was necessary to isolate the ovaries. The ovaries are what contain the eggs of a female. These eggs have half the DNA of a regular cell and, with a sperm cell, can form a zygote.
 |
| Ovaries |
The spleen is a long, thin, organ that filters blood, which helps the immune system recognize dangerous antibodies.
 |
| Spleen |
After the kidneys make urine, it is stored inside the bladder. The bladder is a sac that leads to the urethra, where the urine is excreted.
 |
| Bladder (looks like it has feet!) |
The heart is made of strong cardiac muscle that circulates blood throughout the body. This organ is what makes sure that all parts of the body can get what it needs (eg. oxygen, glucose) as well as can get rid of what it doesn't need (eg. carbon dioxide, waste)
 |
| Heart |
Lungs bring in what every mammal needs to survive, oxygen. Not only that, it also gets rid of what could be toxic to our bodies if its concentration gets too high, carbon dioxide. This is also a body part that comes in pairs. Lungs are filled with tiny little sacs that increase surface area to get maximum oxygen.
 |
| Lungs |
Eyes are sensory organs that allow us to see. Light rays enter the eye lens and the information is interpreted in the brain.
 |
| Eyeball |
 |
| Eye lens (left), gallbladder (right) |
Lastly, the arguably most important organ, the brain. The brain was hard to isolate, due to its delicateness, and therefore took the most time. The brain is the control centre for the entire body. It processes information, and relays an appropriate response to it. The brain controls all our conscious thoughts and all our unconscious thoughts.
 |
| Brain (there wasn't enough time for an isolation) |
After two days of dissection, our pig looked like this:
 |
| Aftermass of dissection |
Wednesday 1 April 2015
Neurons: Structure, Classification, and Reflex Arc
STRUCTURE
Neurons come in different shapes and sizes to serve their function. However, all neurons have three common features, dendrites, cell body, and axons. Dendrites are short terminals that receive nerve impulses. Then the impulse travels to the cell body which contains is able to process the input. As well as that, the cell body is where the site of metabolic reactions happen and where the nucleus is contained. The impulse then travels to the axon, a branch that conducts impulses away from the cell.
Neurons come in different shapes and sizes to serve their function. However, all neurons have three common features, dendrites, cell body, and axons. Dendrites are short terminals that receive nerve impulses. Then the impulse travels to the cell body which contains is able to process the input. As well as that, the cell body is where the site of metabolic reactions happen and where the nucleus is contained. The impulse then travels to the axon, a branch that conducts impulses away from the cell.
Neurons can be classified two ways, by structure, and by function.
By Structure
- Multipolar neuron: has several dendrites, one axon, is commonly found in the brain and spinal cord
- Bipolar neuron: one dendrite, one axon, commonly found in ear, retina, and olfactory area in the brain
- Unipolar neuron: the dendrite and axon are fused together, mainly found in the peripheral nervous system
By Function
- Sensory input: receives stimuli, forms nerve impulses, transmits impulses from sensory receptors to central nervous system (CNS)
- Integration: the link between sensory and motor, processes and integrates incoming sensory info and relays outgoing motor info
- Motor output: transmits info from CNS to effectors (eg. muscles, glands etc.)
REFLEX ARC
A reflex arc is a simple connection that results in a reflex action to a stimulus, consisting of as little as only 3 neurons. Reflexes are sudden, involuntary responses to certain stimuli. Reflex arcs move directly to and from the brain and spinal cord before the brain sections that control voluntary responses can process the sensory information. This is why, for example, when you touch a hot stove with your hand, you can very quickly pull away.
Wednesday 25 March 2015
Saturday 28 February 2015
Three Acts of Translation
In translation, a cell interprets a series of codons found on a mRNA strand. Transfer RNA (tRNA) transfers amino acids to the ribosome to make protein. tRNA contains about 80 nucleotides that folds on itself. Like before, substances are always attached in the 3' end of a chain, in this case the amino acid attaches itself at the 3' end of tRNA. The ribosome takes the amino acid brought by the tRNA and adds it to the growing polypeptide chain.
Act I: Initiation
For the process of initiation to start, energy from the hydrolysis of GTP is needed. Proteins are made in the ribosomes of a cell. A ribosome has two parts, a smaller one and a bigger one. These parts are formed by the rRNA (ribosomal RNA). The smaller section of the ribosome looks for a special genetic sequence that is known as the start codon. A codon is a series of three bases that codes for a specific amino acid. The start codon is 5'AUG3' and it codes for methionine (Met). It attaches itself to the 5' end of the mRNA and moves the mRNA along until it finds the codon. Then, in the bigger part of the ribosome, tRNA arrives, with the help of an initiation factor, with the proper amino acid to build the protein.
Act II: Elongation
The larger unit of the ribosome has three binding sites for tRNA. The P site is where the tRNA holds the growing polypeptide chain, the A site is where another tRNA carries the amino acid for the next codon, and the E site is where the tRNAs leave the ribosome.
Elongation happens in three steps. First is codon recognition, where elongation factors help with hydrogen bonding between the mRNA and tRNA. On the tRNA, there is a section known as the anticodon. The anticodon which is contains the complementary base pairs of the codon. (eg. the start codon, AUG, would have the anticodon of UAC) The anticodon helps the tRNA attach to the right place on the mRNA. Next is the peptide bond formation in which the rRNA helps form a peptide bond between the amino acids in the P site and the A site. This separates the polypeptide chain attached to the tRNA in the P site to the tRNA in the A site. Last is translocation, where the tRNA in the A site is moved to the P site, and because the anticodon remains bonded with the mRNA, the mRNA moves along with it, allowing for a new tRNA with the right amino acid to bond in the A site. At the same time, the tRNA that was in the P site moves to the E site and is released. This ensure that all codons are read 5' to 3'. This process is repeated again and again until the entire protein is made.
Codons are made of three different bases, the last position of the codon is called the wobble position. This wobble is the second way to help decrease mutations in a protein. Usually, in a codon, the most important bases are the first two, if there is a mistake in the last one, it sometimes does not result in a faulty protein. The table below will help illustrate that.
As seen, more than one combination of bases can code for the same amino acid, allowing for some room for error.
Act III: Termination
Termination occurs when one of three stop codons approaches the A site. The stop codons are UAA/UAG/UGA. A release factor binds to the stop codon and hydrolyzes the polypeptide bond between the chain and the tRNA. This frees the protein from the tRNA and the entire translation complex dissociates.
Subscribe to:
Posts (Atom)