The Production and Functions of ATP
The basic process in which ATP is used involves an organic molecule
being phosphorylated by ATP, which produces an organic molecule with a
phosphate group, and reduces ATP to ADP. This phosphorylated molecule
becomes more reactive, thus lowering the activation energy needed for
reactions, mainly used when enzymes are involved. This overview should
demonstrate the importance of ATP- it allows living systems to convert
stored chemical energy to kinetic or heat energy quite efficiently,
resulting in the ability for homeostasis and skeletal movement among
other things.
There are two methods of ATP production, in plants it is a product of
both respiration and the light dependent stage of photosynthesis
whereas in animals it is a result of respiration. Adenosine
triphosphate itself needs energy to be created. It constantly goes
through the cycle of donating a phosphate group and being reduced to
Adenosine diphosphate, and then being phosphorylated back to ATP. The
energy for the formation of ATP in animals is derived from respiration
in which theoretically thirty eight ATP molecules can be restored when
the chemical bonds in a single mole of glucose are broken.
Aerobic respiration commences with the process of glycolysis
(literally: sugar splitting). This process takes place in the cytosol
in the cytoplasm of the cell whereas the remaining processes occur in
the mitochondrial matrices. Two ATP molecules each donate a phosphate
group to a glucose molecule which lowers the activation energy for its
break down into two pyruvate molecules. The intermediate step is where
glucose with the addition of t...
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...actin group, and upon
bonding the tertiary structure of the myosin head changes, causing the
rest of the myosin to move along to accommodate the change in
structure. The reaction between the actin and myosin now causes the
head to release the ADP and Pi which is taken up by a mitochondrion.
In the processes outlined above, this is converted to ATP via
respiration, and ATP is released back into the muscle tissue. This ATP
is needed by the actin-myosin bridge to be released. ATP diffuses into
the myosin head, and the donation of a phosphate group to the bond
lowers the activation energy, allowing the head to be released. It
resumes its original tertiary structure and is available to bridge
with another myosin further down the fibre. This process occurs over
and over again, making the overall contraction a ratchet motion.
In the beginning phases of muscle contraction, a “cocked” motor neuron in the spinal cord is activated to form a neuromuscular junction with each muscle fiber when it begins branching out to each cell. An action potential is passed down the nerve, releasing calcium, which simultaneously stimulates the release of acetylcholine onto the sarcolemma. As long as calcium and ATP are present, the contraction will continue. Acetylcholine then initiates the resting potential’s change under the motor end plate, stimulates the action potential, and passes along both directions on the surface of the muscle fiber. Sodium ions rush into the cell through the open channels to depolarize the sarcolemma. The depolarization spreads. The potassium channels open while the sodium channels close off, which repolarizes the entire cell. The action potential is dispersed throughout the cell through the transverse tubule, causing the sarcoplasmic reticulum to release
The ATP is used for many cell functions including transport work moving substances across cell membranes. It is also used for mechanical work, supplying the energy needed for muscle contraction. It supplies energy not only to heart muscle (for blood circulation) and skeletal muscle (such as for gross body movement), but also to the chromosomes and flagella to enable them to carry out their many functions. A major role of ATP is in chemical work, supplying the needed energy to synthesize the multi-thousands of types of macromolecules that the cell needs to exist. ATP is also used as an on-off switch both to control chemical reactions and to send messages.
When a muscle contracts and relaxes without receiving signals from nerves it is known as myogenic. In the human body, the cardiac muscle is myogenic as this configuration of contractions controls the heartbeat. Within the wall of the right atrium is the sino-atrial node (SAN), which is where the process of the heartbeat begins. It directs consistent waves of electrical activity to the atrial walls, instigating the right and the left atria to contract at the same time. During this stage, the non conducting collagen tissue within the heart prevents the waves of electrical activity from being passed directly from the atria to the ventricles because if this were to happen, it would cause a backflow. Due to this barrier, The waves of electrical energy are directed from the SAN to the atrioventricular node (AVN) which is responsible for transferring the energy to the purkyne fibres in the right and left ventricle walls. Following this, there is a pause before the wave is passed on in order to assure the atria has emptied. After this delay, the walls of the right and left ventricles contract
...st the sacrolemma will depolarized, thus activation potentials along the T-tubules. This signal will transmit from along the T-tubules to sarcroplasmic reticulum's terminal sacs. Next, sarcoplasmic reticulum will release the calcium into the sarcroplasm leading to the next second event called contraction. The released calcium ions will now bind to troponin. This will cause the inhibition of actin and mysoin interaction to be released. The crossbridge of myosin filaments that are attached to the actin filaments, thus causing tension to be exerted and the muscles will shorten by sliding filament mechanism. The last event is called Relaxation. After the sliding of the filament mechanism, the calcium will be slowly pumped back into the scaroplasmic reticulum. The crossbridges will detach from the filaments. The inhibition of the actin and myosin will go back to normal.
For muscles to contract then there must be a presence of calcium within the fibers as it connects with troponin protein and orders tropomyosin to clear the binding sites to allow myosin to attach to these sites, which allows the muscle to contract and produces movement. Without all of these elements working in sync then the function of skeletal muscle would no longer work or even exist.
occurs so the heat deep in the muscles is conserved. Since the vessels are now
Do you know how you are able to run long distances or lift heavy things? One of the reasons is cellular respiration. Cellular respiration is how your body breaks down the food you’ve eaten into adenosine triphosphate also known as ATP. ATP is the bodies energy its in every cell in the human body. We don’t always need cellular respiration so it is sometimes anaerobic. For example, when we are sleeping or just watching television. When you are doing activities that are intense like lifting weights or running, your cellular respiration becomes aerobic which means you are also using more ATP. Cellular respiration is important in modern science because if we did not know about it, we wouldn’t know how we are able to make ATP when we are doing simple task like that are aerobic or anaerobic.
However, in anaerobic respiration (glycolysis and fermentation) only two (2) adenosine triphosphate (ATP) can be obtained. Now, for photosynthesis it is actually a carbon-fixation which is 3CO2+9ATP+6NADPH+H2O--- glyceraldehyde3phosphate+8Pi+9ADP+6NADP which turns out to just be eight-teen (18) ATP per glucose molecules in
The sarcomere is found in structures called myofibrils which make up skeletal muscle fibres. Within the sarcomere there are various different proteins. One of the most significant, myosin is found in the thick filaments of the sarcomere. Although both cells contain myosin, it is important to highlight that smooth muscle cells contain a much lower percentage of myosin compared to skeletal muscle cells. Despite this, myosin filaments in smooth muscle cells bind to actin filaments in a manner similar to that in skeletal muscle cells; although there are some differences. For instance, myosin filaments in smooth muscle cells are saturated with myosin heads so that myosin can glide over bound actin filaments over longer distances, enabling smooth muscle cells to stretch further, whilst in skeleta...
Alkaline phosphatase, or AP, is an enzyme that is responsible for dephosphorylation, or removing phosphate groups, of various types of molecules such as proteins and nucleotides. It has a molecular weight of 140-160 kilo-Daltons and as said in the name, alkaline phosphatase works in an environment with pH values ranging from 7.5-9.5, which is an alkaline, or basic, environment. And according to Sigma-Aldrich, alkaline phosphatase can be used to “to dephosphorylate the 5'-termini of DNA or RNA to prevent self-ligation” (sigmaaldrich.com). Alkaline phosphatase in gram-negative bacteria can be found in the periplasmic space, which is found outside of the cell membrane. Because of this, it is subject to various types of environmental activity, making alkaline phosphatase more resistant to being denatured, inactivated, and degraded, while also giving AP a higher rate of activity.
for a cell to function as part of cellular respiration. ATP is needed to power
Cellular respiration and photosynthesis are the two most important processes that animal and plant cells supply themselves with energy to carry out their life cycles. Cellular respiration takes glucose molecules and combines it with oxygen. This energy results in the form of adenosine triphosphate (ATP), with carbon dioxide and water that results in a waste product. Photosynthesis uses carbon dioxide and combines it with water,
Aerobic requires oxygen and takes place inside the mitochondria of iving cells. The energy is stored as adenosine triphosphate (ATP) Aerobic respiration produces 2890KJ/Mole or 38ATP. This is much more than anaerobic. The
The contraction of a muscle is a complex process, requiring several molecules including ATP and Cl-, and certain regulatory mechanisms [1]. Myosin is motor protein that converts chemical bond energy from ATP into mechanical energy of motion [1]. Muscle contraction is also regulated by the amount of action potentials that the muscle receives [2]. A greater number of actions potentials are required to elicit more muscles fibers to contract thus increasing the contraction strength [2]. Studied indicate that the larger motor units, which were recruited at higher threshold forces, tended to have shorter contraction times than the smaller units [3]. The aims of the experiment were to reinforce the concept that many chemicals are required for skeletal muscle contraction to occur by using the rabbit muscle (Lepus curpaeums) [2]. In addition, the experiment was an opportunity to measure the strength of contraction and to observe the number of motor units that need to be recruited to maintain a constant force as the muscles begin to fatigue [2]. Hypothetically, the rabbit muscle fiber should contract most with ATP and salt solution; and the amount of motor units involved would increase with a decreasing level of force applied until fatigue stage is reached.
In some way, shape, or form energy is one of the several reasons why there is an existence of life on earth. Cellular respiration and Photosynthesis form a cycle of that energy and matter to support the daily functions that allow organisms to live. Photosynthesis is often seen to be one of the most important life processes on Earth. Photosynthesis is a process by which plants use the energy of sunlight to convert carbon dioxide and water into glucose so other organisms can use it as food and energy. It changes light energy into chemical energy and releases oxygen. This way organisms can stay alive and have the energy to function. Chlorophyll is an organelle generally found in plants, it generates oxygen as a result too. As you can see without