topic 1: gas exchange and cellular respiration
Some organisms, such as plants, can trap the energy in sunlight through photosynthesis and store it in the chemical bonds of carbohydrate molecules. The principal carbohydrate formed through photosynthesis is glucose. Other types of organisms, such as animals, fungi, many protozoa, and a large portion of bacteria, are unable to perform this process. Therefore, these organisms must rely on the carbohydrates formed in plants to obtain the energy necessary for their metabolic processes
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Distinguish between anaerobic and aerobic respiration
Distinguish: Make clear the differences between two or more concepts or items.
Distinguish: Make clear the differences between two or more concepts or items.
There are two types of cellular respiration: aerobic and anaerobic. One occurs in the presence of oxygen (aerobic), and one occurs in the absence of oxygen (anaerobic). Both begin with glycolysis - the splitting of glucose.
Some organisms are able to continually convert energy without the presence of oxygen. They undergo glycolysis, followed by the anaerobic process of fermentation to make ATP. Muscle cells can continue to produce ATP when oxygen runs low using lactic acid fermentation. However, this often results in muscle fatigue and pain. Many yeast use alcoholic fermentation to produce ethanol. For this reason, humans have domesticated yeast to use for many commercial purposes including baking as well as beer and wine production.
Advantages of Aerobic Respiration
A major advantage of aerobic respiration is the amount of energy it releases. Without oxygen, organisms can split glucose into just two molecules of pyruvate. This releases only enough energy to make two ATP molecules. With oxygen, organisms can break down glucose all the way to carbon dioxide. This releases enough energy to produce up to 38 ATP molecules. Thus, aerobic respiration releases much more energy than anaerobic respiration.
The amount of energy produced by aerobic respiration may explain why aerobic organisms came to dominate life on Earth. It may also explain how organisms were able to become multicellular and increase in size.
Advantages of Anaerobic Respiration
One advantage of anaerobic respiration, also known as fermentation, is obvious. It lets organisms live in places where there is little or no oxygen. Such places include deep water, soil, and the digestive tracts of animals such as humans Another advantage of anaerobic respiration is its speed. It produces ATP very quickly. For example, it lets your muscles get the energy they need for short bursts of intense activity such as a sprint. Aerobic respiration, on the other hand, produces ATP more slowly
Some organisms are able to continually convert energy without the presence of oxygen. They undergo glycolysis, followed by the anaerobic process of fermentation to make ATP. Muscle cells can continue to produce ATP when oxygen runs low using lactic acid fermentation. However, this often results in muscle fatigue and pain. Many yeast use alcoholic fermentation to produce ethanol. For this reason, humans have domesticated yeast to use for many commercial purposes including baking as well as beer and wine production.
Advantages of Aerobic Respiration
A major advantage of aerobic respiration is the amount of energy it releases. Without oxygen, organisms can split glucose into just two molecules of pyruvate. This releases only enough energy to make two ATP molecules. With oxygen, organisms can break down glucose all the way to carbon dioxide. This releases enough energy to produce up to 38 ATP molecules. Thus, aerobic respiration releases much more energy than anaerobic respiration.
The amount of energy produced by aerobic respiration may explain why aerobic organisms came to dominate life on Earth. It may also explain how organisms were able to become multicellular and increase in size.
Advantages of Anaerobic Respiration
One advantage of anaerobic respiration, also known as fermentation, is obvious. It lets organisms live in places where there is little or no oxygen. Such places include deep water, soil, and the digestive tracts of animals such as humans Another advantage of anaerobic respiration is its speed. It produces ATP very quickly. For example, it lets your muscles get the energy they need for short bursts of intense activity such as a sprint. Aerobic respiration, on the other hand, produces ATP more slowly
Draw the chemical equation of aerobic and anaerobic respiration
Draw: Represent by means of a labelled, accurate diagram or graph, using a pencil. A ruler (straight edge) should be used for straight lines. Diagrams should be drawn to scale. Graphs should have points correctly plotted (if appropriate) and joined in a straight line or smooth curve.
Draw: Represent by means of a labelled, accurate diagram or graph, using a pencil. A ruler (straight edge) should be used for straight lines. Diagrams should be drawn to scale. Graphs should have points correctly plotted (if appropriate) and joined in a straight line or smooth curve.
Distinguish between fermentation and cellular respiration.
Distinguish: Make clear the differences between two or more concepts or items.
Distinguish: Make clear the differences between two or more concepts or items.

Explain how cellular respiration produces ATP from glucose and other molecules with high potential energy.
Explain: Give a detailed account including reasons or causes.
Explain: Give a detailed account including reasons or causes.

The release of energy when glucose is oxidized is used to help synthesizeATP from ADP and Pirather than release all the energy in the form of heat.The potential energy stored in glucoses bonds is converted to kineticenergy in the form of heat and light and this heat and light is harnessed forATP synthesis
Describe the structure of the heart and how it functions
Describe: Give a detailed account
Describe: Give a detailed account

The human heart is a hollow, upside-down, pear-shaped shell. The inside of the heart is divided into four chambers, the left and right atria and the left and right ventricles, which periodically fill with blood and empty.
The two atria form the curved top of the heart. The ventricles meet at the bottom of the heart to form a pointed base which points toward the left side of the chest. The left ventricle contracts most forcefully, so the heart beat is felt most strongly on the left side of the chest.
A wall, called the septum, separates the right and left sides of the heart. A valve connects each atrium to the ventricle below it. The mitral or bicuspid valve connects the left atrium with the left ventricle. The tricuspid valve connects the right atrium with the right ventricle.
The two atria form the curved top of the heart. The ventricles meet at the bottom of the heart to form a pointed base which points toward the left side of the chest. The left ventricle contracts most forcefully, so the heart beat is felt most strongly on the left side of the chest.
A wall, called the septum, separates the right and left sides of the heart. A valve connects each atrium to the ventricle below it. The mitral or bicuspid valve connects the left atrium with the left ventricle. The tricuspid valve connects the right atrium with the right ventricle.
Explain how the factors that affect heart rate
Explain: Give a detailed account of causes, reasons or mechanisms
Explain: Give a detailed account of causes, reasons or mechanisms

There are many factors that affect your heart rate. The heart rate can speed up or slow down because of stress, exercise, medication, trauma or illness. Even breathing can cause slight fluctuations in heart rate. Most of the time a person does not really think about changes in his heart rate.
Other factors that can affect heart rate
Other factors that can affect heart rate
- Air temperature: When temperatures (and the humidity) soar, the heart pumps a little more blood, so your pulse rate may increase, but usually no more than five to 10 beats a minute.
- Body position: Resting, sitting or standing, your pulse is usually the same. Sometimes as you stand for the first 15 to 20 seconds, your pulse may go up a little bit, but after a couple of minutes it should settle down. Emotions: If you’re stressed, anxious or “extraordinarily happy or sad” your emotions can raise your pulse.
- Body size: Body size usually doesn't usually change pulse. If you’re very obese, you might see a higher resting pulse than normal, but usually not more than 100.
- Medication use: Meds that block your adrenaline (beta blockers) tend to slow your pulse, while too much thyroid medication or too high of a dosage will raise it
- Digestion : In a digestive process, the intestines would require additional blood circulation and therefore a possible heart rate increase can be seen
Compare and contrast the structure of arteries, veins and capillaries
Compare and contrast: Give an account of the similarities and differences between two (or more) items or situations, referring to both (all) of them throughout.
Compare and contrast: Give an account of the similarities and differences between two (or more) items or situations, referring to both (all) of them throughout.
Outline the function of plasma
Outline: Give a brief account or summary.
Outline: Give a brief account or summary.

Plasma is a pale-yellowish, watery solution that suspends all of the other parts of the blood. It makes up about 55% of the total volume of our blood. Plasma itself is made up of 91.5% water. It acts as a solvent for important proteins, nutrients, electrolytes, gases, and other substances essential to life.
Plasma is made mostly of water. This allows our blood to flow freely through our blood vessels, transporting a variety of substances throughout our entire body. We can think of plasma as the river upon which particles can travel and be delivered where needed. Red blood cells, white blood cells, and platelets are carried in the current of the plasma, transporting oxygen, providing an immune response, and delivering clotting agents when we have a cut.
Plasma is made mostly of water. This allows our blood to flow freely through our blood vessels, transporting a variety of substances throughout our entire body. We can think of plasma as the river upon which particles can travel and be delivered where needed. Red blood cells, white blood cells, and platelets are carried in the current of the plasma, transporting oxygen, providing an immune response, and delivering clotting agents when we have a cut.
Explain how adaptations of red blood cells, including shape, structure and the presence of haemoglobin, make them suitable for the transport of oxygen
Explain: Give a detailed account of causes, reasons or mechanisms
Explain: Give a detailed account of causes, reasons or mechanisms

The oxygen carried in your red blood cells is stored in a special protein known as hemoglobin. A single hemoglobin molecule is made of four identical sub-units. Each sub-unit has a heme component, aglobin chain and an iron atom bound to the heme section. Red blood cells are completely lacking in most other common cellular parts, such as a nucleus with DNA, or mitochondria.
Oxygen is able to bind to each of the iron atoms, meaning that a single hemoglobin molecule is able to carry up to four oxygen molecules at its maximum capacity. Interestingly, the structure of hemoglobin makes it such that the more oxygen that is bound to one of the sub-units, the more other oxygen molecules are attracted to the remaining iron atoms.
Oxygen is able to bind to each of the iron atoms, meaning that a single hemoglobin molecule is able to carry up to four oxygen molecules at its maximum capacity. Interestingly, the structure of hemoglobin makes it such that the more oxygen that is bound to one of the sub-units, the more other oxygen molecules are attracted to the remaining iron atoms.
Key Terms:
surface area
SA:Volume ratio pulmonary systemic atria atrioventricular tricuspid valve bicuspid valve pathogen white blood cell |
heart
blood vessels arteries veins septum AV node arterioles innervated vaccination blood clot |
capillaries
blood plasma cardiac muscle oxygenated deoxygenated platelets red blood cells fibrinogen gibrin |
cardiac cycle
systol diastole coronary arteries erythrocytes haemoglobin oxyhaemoglobin phagocytosis secondary immune response |
medulla
ventricle vena cava aorta pseudopodia lymphocytes antibodies antigen memory cell immune |
Classroom Materials:
Surface Area to Volume ratio worksheet
Size Matters worksheet
Osmosis and Diffusion review
Comparing Human Circulation System with other species reading activity
Circulatory System (study notes)
The Heart Coloring activity
Diagram of the Heart
Exercise practical (in class design)
Heart Dissection practical
The Circulatory System Cloze activity
Blood Vessels Worksheet
Anatomy of the blood
Circulatory System Review
Surface Area to Volume ratio worksheet
Size Matters worksheet
Osmosis and Diffusion review
Comparing Human Circulation System with other species reading activity
Circulatory System (study notes)
The Heart Coloring activity
Diagram of the Heart
Exercise practical (in class design)
Heart Dissection practical
The Circulatory System Cloze activity
Blood Vessels Worksheet
Anatomy of the blood
Circulatory System Review
Part 1 Circulatory System Overview
Part 2 The Heart
Part 3 The Vessles
Part 4 The Blood
Useful Links:
Circulation from BBC Bitesize
Video clip on Heart Circulation
Active Book animation on page 55
Video clip on Heart Disease
PBS presentation on Circulation
Immunity animation from McGraw Hill
A nice review of the Circulatory System from KScience
Another KScience animation to help practice Labeling the Heart
Measles and the anti-vaccine 'debate' , BBC News
Video Clips:
Circulation from BBC Bitesize
Video clip on Heart Circulation
Active Book animation on page 55
Video clip on Heart Disease
PBS presentation on Circulation
Immunity animation from McGraw Hill
A nice review of the Circulatory System from KScience
Another KScience animation to help practice Labeling the Heart
Measles and the anti-vaccine 'debate' , BBC News
Video Clips:
This video shows how Paramecium eat. Paramecium is a genus of unicellular ciliate protozoa, commonly studied as a representative of the ciliate group. Its shape resembles that of a grain of rice. The cell ranges from about 50 to 350 �m in length (more or less one tenth of a millimetre) and is covered with simple cilia, allowing the cell to move at speeds of approximately 12 body lengths per second. The cilia act like oars and move in one direction.There is a deep oral groove containing inconspicuous tongue-like compound oral cilia (as found in other peniculids) used to draw food inside. In general, they feed on bacteria and other small cells, making them heterotrophs. Osmoregulation is carried out by a pair of contractile vacuoles, which actively expel water from the cell absorbed by osmosis from its surroundings.[1] They are relatively large protists and can easily be seen with a medium-power microscope.
Paramecia are widespread in freshwater environments, and are especially common in scums. Recently, some new species of Paramecium have been discovered in the oceans.
Certain single-cell eukaryotes such as Paramecium are examples for exceptions to the universality of the genetic code: in their translation systems a few codons differ from the standard ones.
Paramecia are widespread in freshwater environments, and are especially common in scums. Recently, some new species of Paramecium have been discovered in the oceans.
Certain single-cell eukaryotes such as Paramecium are examples for exceptions to the universality of the genetic code: in their translation systems a few codons differ from the standard ones.
For most of history, scientists weren't quite sure why our hearts were beating or even what purpose they served. Eventually, we realized that these thumping organs serve the vital task of pumping clean blood throughout the body. But how? Edmond Hui investigates how it all works by taking a closer look at the heart's highly efficient ventricle system
Hank takes us on a trip around the body - we follow the circulatory and respiratory systems as they deliver oxygen and remove carbon dioxide from cells, and help make it possible for our bodies to function.
3D How the Heart Works
Hank tells us about the team of deadly ninja assassins that is tasked with protecting our bodies from all the bad guys that want to kill us - also known as our immune system.
This amazing video shows aWhite Blood Cell Chases Bacteria. Video by David Rogers, Vanderbilt University
The first ever vaccine was created when Edward Jenner, an English physician and scientist, successfully injected small amounts of a cowpox virus into a young boy to protect him from the related (and deadly) smallpox virus. But how does this seemingly counterintuitive process work? Kelwalin Dhanasarnsombut details the science behind vaccines
Seth Berkley explains how smart advances in vaccine design, production and distribution are bringing us closer than ever to eliminating a host of global threats -- from AIDS to malaria to flu pandemics
Vaccine-autism claims, "Frankenfood" bans, the herbal cure craze: All point to the public's growing fear (and, often, outright denial) of science and reason, says Michael Specter. He warns the trend spells disaster for human progress.
Tal Golesworthy is a boiler engineer -- he knows piping and plumbing. When he needed surgery to repair a life-threatening problem with his aorta, he mixed his engineering skills with his doctors' medical knowledge to design a better repair job.
This amazing device could 'eat' bad cholesterol in your arteries.