#they use their DIGESTIVE TRACTS to pump BLOOD because they have TOO MUCH LEG
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ONE HOUR LEFT TO VOTE FOR SEA SPIDERS, THE ONLY ANIMAL IN THIS TOURNAMENT BRACKET THAT OUTSOUCES MULTIPLE MAJOR BODILY FUNCTIONS TO ITS LEGS, TRULY THE MOST LEG THAT ANY ANIMAL HAS EVER BEEN, AND OBJECTIVELY A MUCH WEIRDER ANIMAL THAN JERBOAS.
VOTE NOW FOR THE MOST ELDRITCH CREATURE IN THE TOURNAMENT BRACKET, OR I WILL NEVER FORGIVE JERBOAS
Round 1 Match 8
Jerboa weirdness: "bro has stilts for legs. a dang bird-mouse. sneefing and snorfing"
Sea Spider weirdness: "At first glance they kinda look like spiders but their anatomy is so freakish and different it's just insane (some have even postulated they may not even be arthropods in the first place). Their intestine branches off and runs through each one of their legs. They're so thin they don't need a dedicated respiratory system and can breath through simple diffusion (through their legs, mostly. They're like 90% leg.). Some species are so small each of their muscles consists of one single cell while other species can have leg spans of about 50 cm."
#weird animal tournament#weirdanimaltournament#sea spiders#pycnogonid#weirdanimal-tournament#please please please don’t let jerboas eliminate these guys#they use their DIGESTIVE TRACTS to pump BLOOD because they have TOO MUCH LEG#THATS SO CURSED#tournament bracket propaganda
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do you have any recs for poisons to use in a whump? like not to instantly kill the whumpee/victim, but to make them hurt for a long and copious amount of time before they die? there would be a window in which someone could try and save them (and potentially succeed) as well. I'm writing a whump right now and am in some desperate need of help because I can't find any suitable... thanks! I know it's a lot to ask, but if you have any sources to go to or any ideas that'd be great!
I have many! Here are the top 5 that come to mind and are potentially recognizable to your audience.
Remember that anything I say here can be affected by magic, sci-fi, or really anything you want :)
Ricin is a great one! It’s often been sent to government officials so there’s some fairly easy to find info on it, people got curious as to what exactly it was and how it worked. What I know about it is as follows
It can be inhaled, eaten, or injected but is most potent when inhaled or injected.
It takes a deliberate act to be exposed to ricin. There is no natural way to expose someone to it or be exposed to it. Exposure is a deliberate action.
It is a protein in a castor oil plant.
If heated, it is no longer toxic
It can take up to a day for symptoms to show up but it can kill you within three days. If the victim survives more than five days, survival is likely
There is no known antidote to ricin
Victims who ingest the protein get severe nausea and diarrhea. If it is inhaled, the patient will also have difficulty breathing and fluid will build up in the lungs. They end up with an irregular heartbeat, low blood pressure, and seizures. This can last for up to a week. The patient can die of shock and multiple organ failure.If you ingest the protein, treatment can usually reverse the symptoms and patients will survive, though they may suffer long-term organ damage. A man was poisoned with ricin in Las Vegas in February of 2008 and fell in to a coma for more than a month. The Bulgarian writer Markov first showed a fever, was admitted to the hospital, and died three days later.
Another awesome one is Fugu Poison (Tetrodotoxin) This one is most commonly found in marine animals and fish! It is found in the Japanese delicacy Fugu. People still die from improperly prepared or sold fugu. Here is what I know
You only need a little bit to die. I believe roughly 25 milligrams can kill a 75kg human.
Most commonly it’s been ingested, I don’t know if there is another way to take it or be exposed to it.
There is no known antidote save for stomach pumping and forced vomiting, although some people have made a lucky recovery
It is believe to be 1,200 more potent than cyanide
It can take anywhere from 20 minutes to twenty-four hours to kill you
Symptoms begin approximately 3-45 minutes after ingestion.
Symptoms include: lightheadedness, vomiting, dizziness and weakness, muscle twitching, aphonia, pleuretic chest pain and convulsions, hypotension, depressed corneal reflexes and fixated diagonal pupils, headaches, difficulty breathing, paralysis, respiratory paralysis and asphyxiation.
A dramatic poison is strychnine. This one isn’t as toxic but I enjoy the style of it. It’s actually fairly common and is found in many pesticides, all those google searches for “Strychnine for sale” aren’t by psychopaths by probably by people needing pest control. Probably.
You can ingest it, inhale it, or have it injected.
It is a white, odorless, colorless powder. (Some say it tastes bitter)
It kills through dramatic and excruciating muscle spasms that continue until your body dies from exhaustion and you also can’t breathe anymore
Initially, a victim might just seem excitable (though they would also be in pain)
Symptoms occur after 15-60 minutes
Symptoms include: Agitation, apprehension or fear, ability to be easily startled, restlessness, painful muscle spasms possibly leading to fever and to kidney and liver injury, uncontrollable arching of the neck and back, rigid arms and legs, jaw tightness, muscle pain and soreness, difficulty breathing, dark urine, initial consciousness and awareness of symptoms, respiratory failure (inability to breathe), possibly leading to death, brain death, shortness of breath, unbearable feelings of anxiety, restlessness, twitching and spasms gradually develop and lead to violent tetanic seizures in which the head is bent right back to the buttocks, so that the spine may be broken. Breathing may cease for intervals of one to two minutes at a time; in this event the seizures may also stop, only to recommence at the least excitation - a loud noise or a gentle touch - until death from exhaustion finally supervenes.
There is no known antidote
If a victim survives past 24 hours, recovery is likely
Want to poison by making them eat it? Feed them amatoxin. It is found most commonly in Death Cap Mushrooms, which look like other mushrooms so cook up something tasty and kill a whole dinner party.
Apparently it tastes very good
I believe it must be ingested
It remains toxic whether raw or cooked
After 6-12 hours nausea, abdominal cramps, profuse watery diarrhea, and signs of dehydration show up
After that, the victim seems to recover but their liver will continue fail
Death occurs after 3-7 days although death may occur within the first 24 hours from massive fluid loss.
Symptoms include: espiratory tract, headache, dizziness, nausea, shortness of breath, coughing, insomnia, diarrhea, gastrointestinal disturbances, back pain, urinary frequency, liver and kidney damage, or death if ingested or inhaled
Symptoms potentially include: irritation, burns, redness, severe pain, and could be absorbed through the skin, irritation, corneal burns, and eye damage if absorbed via eyes.
Besides liver transplants and some penicillins, there are little treatments or antidotes.
I read somewhere that victims often slip into a coma and die, but I can’t find the source so that’s debatable. This is the internet after all.
You could go for some significance, foreshadowing, or easter eggs by using Hemlock. It was famously used by Socrates as his death penalty.
Drinking it’s tea can make you feel initially drunk
Ingestion is the most common and effective way to suffer but prolonged contact can also lead to poisoning.
Some mythology says that the plant didn’t turn toxic until after the blood of Jesus fell on it after his crucifixion
Poisons last on the plant even up to three years after death
Goats seem unaffected
Symptoms show up as quickly as 30 minutes after exposure
Symptoms include:trembling, burning in the digestive tract, increased salivation, dilated pupils, muscle pain, muscle weakness or muscle paralysis, rapid heart rate followed by a decreased heart rate, loss of speech, convulsions, unconsciousness or coma, central nervous system depression, respiratory failure, acute rhabdomyolysis, or breakdown of damaged skeletal muscle, acute renal failure, death, seizures, rapid heart rate, frothing at the mouth, and respiratory distress, nervous trembling, salivation, lack of coordination, rapid, weak pulse, respiratory paralysis, occasionally bloody feces and gastrointestinal irritation
Death occurs 48-72 after 48-72
There is no antidote although doctors will likely try to assist in breathing, secure your airway, and remove the hemlock from your digestion track,
I hope that was helpful! I would recommend doing further research on your poison of choice to really get the details right but make sure not to bog down your writing with too much explanation, most people far prefer angst to hyper-accuracy.
If you would like, I would love to be tagged when you finish your work! I’m always on the lookout for new fan fiction and whump 👀
Good luck with your writing!
#whump prompts#writing prompts#writing reference#writing resources#friendly-neighborhood-ash#poison#brief religion mention#heartless answers
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If you have ever experienced swelling in your legs (or your hands or feet for that matter) you know how painful it can become.
There are many reasons this swelling, known as edema, or the retention of fluids in the body, can occur:
A sedentary lifestyle—sitting or staying in one position for too long
Eating too much processed foods and foods high in salt
Poor circulation
PMS
Side effects of some medications
Pregnancy
Often, a bit of swelling in your legs can be normal after standing or sitting for the day or during pregnancy for example, but chronic leg and ankle swelling—peripheral edema—can also signal a more serious underlying issue such as kidney disease, heart failure or liver disease, so it is always best to consult a physician if this swelling persists.
For cases of occasional swelling however, there are herbal remedies that can be helpful for reducing the swelling and helping your body eliminate any excess fluids. One such herb is parsley.
It Used To Be Recommended by Hippocrates
The word parsley is actually derived from two Greek words: “petrose,” meaning rock, as it often pops through rocky terrain and stone walls; and “selenium,” the ancient name for celery. When put together, it literally means “rock celery.”
There are essentially two types of parsley—curly parsley and Italian parsley (flat leaves) which tends to be the hardier of the two.
While parsley is used as a garnish in almost every restaurant and home in North America, more often than not, we tend to pick it off the dish and leave it to the side.
But studies show that eating that parsley garnish can help protect you from a variety of diseases and ailments including, digestive disorders, urinary tract problems, menstrual pain, asthma, allergies, as well as help to lower blood pressure, improve your bone health, your breath and even help in cases of bronchitis.
In ancient times, Hippocrates recommended parsley as a general tonic for kidney stones and rheumatism as well as an antidote for poison. And according to “The Green Pharmacy Herbal Handbook,” parsley is a wonderful diuretic that helps the kidneys remove excess fluids from the body (edema).
Parsley Is a Natural Diuretic
A study published in 2002 in the Journal of Ethnopharmacology, showed that “parsley acts as a diuretic by inhibiting the sodium and potassium ion pumps, influencing the process of osmosis and increasing the flow of urine.”
Parsley is also rich in potassium and because most chemically produced diuretics actually lower potassium levels in the body, parsley also assures you do not experience this common side effect of these pharmaceutical drugs.
Another 2009 Brazilian study titled, “Diuretic and hypotensive activity of aqueous extract of parsley seeds” showed similar results for parsley and suggests that parsley can not only increase urinary flow, but also decrease blood pressure as well.
Parsley Tea Recipe for Edema
According to Dr. John R. Christopher, renowned author and America’s foremost herbalist, you should drink at least two quarts (64 oz.) of strong parsley tea per day to achieve maximum results.
You can increase the amount of parsley tea to a cup every hour if you feel the need. When making your tea, however, he also suggests that you use the “fresh light-green leaves,” along with the roots and seeds, if available.
Instructions:
Chop the leaves and roots into small pieces (you can also pre-chop the parsley and store them in an airtight glass container in the fridge for up to a week.)
Place approximately ¼ cup of parsley into an infusion basket.
Pour over a cup of boiled water or submerge into a tea pot.
Let the mixture steep for 5 to 7 minutes.
Remove the basket or strain the tea.
Add honey, lemon or ginger for flavor if desired.
Always drink parsley tea warm for the best effects.
As well as drinking tea, don’t forget to use other techniques to reduce swelling such as raising your legs by putting your legs on pillows to raise them above your heart when lying down.
Also exercise your legs as this helps pump fluid from your legs back to your heart.
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The post This Powerful Tea Is The Best Remedy For Swollen Legs appeared first on Daily Health Post.
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New Post has been published on Biology Dictionary
New Post has been published on https://biologydictionary.net/muscle/
Muscle
Muscle Definition
A muscle is a group of muscle tissues which contract together to produce a force. A muscle consists of fibers of muscle cells surrounded by protective tissue, bundled together many more fibers, all surrounded in a thick protective tissue. A muscle uses ATP to contract and shorten, producing a force on the objects it is connected to. There are several types of muscle, which act on various parts of the body.
Structure of Muscle
A muscle consists of many muscle tissues bundled together and surrounded by epimysium, a tough connective tissue similar to cartilage. The epimysium surrounds bundles of nerve cells that run in long fibers, called fascicles. These fascicles are surrounded by their own protective layer, the perimysium. This layer allows nerves and blood to flow to the individual fibers. Each fiber is then wrapped in an endomysium, another protective layer. As seen in the image below, a muscle is arranged in a basic pattern of bundled fibers separated by protective layers.
These layers and bundles allow different parts of a muscle to contract differently. The protective layer surrounding each bundle allows the different bundles to slide past one another as they contract. The epimysium connects to tendons, which attach to the periosteum connective tissue that surrounds bones. Being anchored to two bones allows movement of the skeleton when the muscle contracts. A different type of muscle surrounds many organs, and the epimysium connects to other connective tissues to produces forces on the organs, controlling everything from circulation to food processing.
Function of Muscle
Whether it is the largest muscle in your body or the tiny muscle controlling the movement of your eye, every muscle functions in a similar manner. A signal is sent from the brain along a bundle of nerves. The electronic and chemical message is passed quickly from nerve cell to nerve cell and finally arrives at the motor end plate. This interface between the muscle and nerve cells releases a chemical signal, acetylcholine, which tells the muscle fiber to contract. This message is distributed to all the cells in the fiber connected to the nerve.
This signal causes the myosin proteins to grab onto the actin filaments around them. These are the purple proteins in the image below. Myosin uses ATP as an energy source to crawl along the green filament, actin. As you can see, the many small heads of the myosin fibers crawling along the actin filaments effectively shortens the length of each muscle cell. The cells, which are connected end-to-end in a long fibers, contract at the same time and shorten the whole fiber. When a signal is sent to an entire muscle or group of muscles, the resulting contraction results in movement or force being applied.
A muscle can be used in many different ways throughout the body. A certain muscle might contract rarely with a lot of force, whereas a different muscle will contract continually with minimal force. Animals have developed a plethora of uses for the forces a muscle can create. Muscles have evolved for flying, swimming, and running. They have also evolved to be pumps used in the circulatory and digestive systems. The heart is a specialized muscle, which is uses exclusively for pumping blood throughout the body. These different types of muscle will be discussed below.
Types of Muscle
Skeletal Muscle
When you think of a muscle, most people generally think of a skeletal muscle. The biceps, triceps, and quadriceps are all common names for muscles that body builders tend to focus on. In fact, these general muscles are often composed of many small muscles that attach to different places to give a joint its full range of motion. Skeletal muscle is a striated muscle. This means that each muscle fiber has striations, or linear marks, which can be seen when this muscle is put under a microscope. The striations correspond to the sarcomeres present in striated muscles, which are highly organized bundles of muscle cells which can contract quickly in concert.
Skeletal muscle is controlled via the somatic nervous system, also known as the voluntary nervous system. Point your finger to the ceiling. This is your somatic nervous system in action, controlling your skeletal muscles.
Cardiac Muscle
Cardiac muscle, while similar to skeletal muscle in some ways, is connected to the autonomous nervous system. This system controls vital organs such as the heart and lungs and allows us to not have to focus on pumping our heart each time it needs to beat. While there is a certain amount of conscience control we have over the autonomous nervous system, it will always kick in when we are unconscious. For instance, you can hold your breath if you like but you do not have to remember to breathe all the time. Cardiac muscle surround the chambers of the heart and is used to pump blood through the body.
Cardiac muscle is similar to skeletal muscle in that it is striated. Unlike skeletal muscle, cardiac muscle fibers are arranged in a branching pattern instead of a linear pattern. Both skeletal muscle and cardiac muscle need to contract quickly and often, which is why the striations can be seen.
Smooth Muscle
Unlike skeletal and cardiac muscle, smooth muscle is not striated. This is because the individual muscle cells are not perfectly aligned into sarcomeres. Instead, they are displaced throughout the fibers. This gives smooth muscle the ability to contract for longer, although the contraction happens more slowly. Consider the muscle that contracts the sphincter on your bladder. This muscle may need to stay clamped shut for hours at a time and only gets a minute of relief when you go to the bathroom. Many other smooth muscles operate in the same manner.
Like cardiac muscle, smooth muscle is mostly controlled by the autonomous nervous system. The many muscles that line your digestive tract work together to move food through the digestive system. Muscles attach to your hair follicles that all your hairs to stand up when it’s cold. Smooth muscle is almost everywhere in your body and aids in everything from circulation to digestion.
Quiz
1. A big, strong bear goes in a cave to hibernate for winter. In the spring a skinny, weak bear emerges. What happened to the bear’s muscles? A. They stayed the same size, they were just hidden under fat B. The bear used them as energy during hibernation C. The bear’s fur is thinner, making him look weaker
Answer to Question #1
B is correct. Muscles that aren’t being used are wasted energy. The bear will use the protein and nutrients available in its muscle and fat cells to survive through the winter. Some muscles, like the diaphragm used to control breathing, will not see a loss in mass. Other muscles, like the leg muscles, are not needed during hibernation and will be allowed to atrophy, or decrease in size.
2. Growing muscles is known as hypertrophy. Body builders do this when they work out to increase the size of their muscle. Often, days after a good workout, the muscle that got worked will hurt slightly. What causes this? A. Lactic Acid buildup B. Not enough Protein! C. Microscopic tears in the muscle fibers
Answer to Question #2
C is correct. When you really push your muscles to the limits, they begin to tear. If you try to lift too much weight, you will tear you muscles in half. By doing repetitive sets of a heavy weight, a muscle will obtain tiny tears in various muscle fibers. When these tears heal, more muscle cells are used and the overall mass and size of the muscle increase.XX
3. Endurance runners are told to eat pasta the night before a big run. Why is this helpful? A. Pasta doesn’t slosh around while you are running B. Carbohydrates help you soak up more water, which helps you run C. Carbohydrates break down easily and load your cells with ATP
Answer to Question #3
C is correct. The carbs found in pasta can easily be broken down into glucose, which muscle cells convert to ATP to store energy. This ATP is then used to activate the myosin heads and help them walk along the actin filament. In reality, any balanced meal will load your cells up with glucose and prepare you for exercise.
References
Lodish, H., Berk, A., Kaiser, C. A., Krieger, M., Scott, M. P., Bretscher, A., . . . Matsudaira, P. (2008). Molecular Cell Biology 6th. ed. New York: W.H. Freeman and Company.
Nelson, D. L., & Cox, M. M. (2008). Principles of Biochemistry. New York: W.H. Freeman and Company.
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My biggest surgery-related fears
1. Paralysis
Obviously this one takes the cake. I ran varsity cross-country all four years of high school. My whole education and career choice centers around me preferring to walk around the woods, rather than sit at a desk or stand in a lab. If my ability to walk independently takes a hit, my whole life plan is absolutely fucked. I’m cool with not playing full-contact hockey, or whatever other limits the doc puts on me, but I need these legs in top shape ASAP.
2. Catheters
If you’ve never had a catheter or a urodynamics study, CONSIDER YOURSELF GRATEFUL. I’ve endured it twice (possibly more as a kid in the follow-up to my first surgery, but I was too young and too doped up to remember) and it is a nightmare. The burning, the sensation of having something snake up there, the blood in your piss the next day...clearly the urethra is designed as a one-way street, and I greatly prefer it to stay that way. When I wake up tomorrow, there’ll be a Foley catheter in me, that much is unavoidable. For the unenlightened, that means there’ll be a balloon literally inflated in my bladder, and a hose sticking out my Johnson. I just pray that I’m knocked out when they put it in, knocked out when they take it out, and that it’s covered by a sheet so I won’t have to see it until it’s gone.
2A: Urine Retention
So currently I have the opposite of this problem: I can hold about 400-500ml before my bladder gives me a 2-minute warning and lets everything loose. Some folks with the same condition as me can’t piss even when they want to, which essentially means they have to use a catheter every 3-4 hours FOR THE REST OF THEIR LIFE. That shit will not fly with me, I hate it enough even when someone else puts it in for me. And it’s so much responsibility...let’s say I get a bit drunk, forget to cath, pass out and sleep for 10 hours straight (not unheard of on my average weekend). Oops, either my bladder has literally exploded inside my body and killed me, or my kidneys are flooded and about to fail! Nothing quite like the idea of one of your own organs becoming a ticking time bomb, waiting to ruin your body.
3. Medication
I’ve discussed this with my doctor at length, and he says the absolute minimum of what I’ll be taking post-surgery is oxycodone, pregabalin, and baclofen. All of those are sedatives. Now, my brain’s already pretty sedated at baseline; I take a caffeine pill every day to get out of bed, and chief high-nicotine e-juice literally all day. Having taken opiates after my wisdom tooth surgery, and having tried Valium before (which is normally part of the post-surgical cocktail) I can safely say my brain will NOT function enough for me to go to work or class so long as I’m on even one of those. Combining them...well, isn’t that how Jimi Hendrix died? Not to mention the antibiotics (which fuck my digestive tract up without fail) and steroids (prednisone made my acne unbearable) they’ll have me on, which are honestly the least of my worries right now.
4. Infection
I saw a picture in a support group of a lady whose stitches had popped out early, and her incision was wide open and brimming with pus. It took all my composure to not vomit all over my keyboard. I want my back closed up, locked tight, welded shut, whatever it takes to stay closed and heal before I can look in the mirror and see how nasty it looks.
5. More Surgery
I’ve always hated the doctor’s office. I hate medication, I hate feeling frail and fragile, I hate not being able to get out and do stuff like everyone else. If everything goes according to plan, this is the last surgery I’ll need for a long while. Of course, this is my second detethering, which already increases the chances I’ll need a third or fourth down the road. Furthermore, to deal with complications or symptoms that don’t recover, a lot of people need additional work done: stomas (no thanks I don’t want bags hanging off my belly), MACE or Mitrofanoff (other holes in your belly, equally gross) Botox injections (FYI Botox is literally poison, I know it’s also medicine but I still can’t get over that) nerve stimulators and pain pumps (please don’t turn me into a robot, most of my organic parts are doing fine) and the list goes on. Plus, I’m on my family’s A1 Cadillac health insurance right now, and I doubt I’ll have coverage like that come age 25, so this had better be a one-and-done deal.
6. Sexuality
So, this may be TMI, but one of the symptoms I’ve been dealing with is decreased sensation “below the belt”. Right now it’s manageable; takes me a bit longer to finish than it used to, but everything’s in working order. For now. It better stay that way, because if I can’t get my rocks off in a reasonable amount of time at least a couple times a week, I will literally set fire to something. Testosterone isn’t meant to be bottled up!
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New Post has been published on Biology Dictionary
New Post has been published on https://biologydictionary.net/muscle/
Muscle
Muscle Definition
A muscle is a group of muscle tissues which contract together to produce a force. A muscle consists of fibers of muscle cells surrounded by protective tissue, bundled together many more fibers, all surrounded in a thick protective tissue. A muscle uses ATP to contract and shorten, producing a force on the objects it is connected to. There are several types of muscle, which act on various parts of the body.
Structure of Muscle
A muscle consists of many muscle tissues bundled together and surrounded by epimysium, a tough connective tissue similar to cartilage. The epimysium surrounds bundles of nerve cells that run in long fibers, called fascicles. These fascicles are surrounded by their own protective layer, the perimysium. This layer allows nerves and blood to flow to the individual fibers. Each fiber is then wrapped in an endomysium, another protective layer. As seen in the image below, a muscle is arranged in a basic pattern of bundled fibers separated by protective layers.
These layers and bundles allow different parts of a muscle to contract differently. The protective layer surrounding each bundle allows the different bundles to slide past one another as they contract. The epimysium connects to tendons, which attach to the periosteum connective tissue that surrounds bones. Being anchored to two bones allows movement of the skeleton when the muscle contracts. A different type of muscle surrounds many organs, and the epimysium connects to other connective tissues to produces forces on the organs, controlling everything from circulation to food processing.
Function of Muscle
Whether it is the largest muscle in your body or the tiny muscle controlling the movement of your eye, every muscle functions in a similar manner. A signal is sent from the brain along a bundle of nerves. The electronic and chemical message is passed quickly from nerve cell to nerve cell and finally arrives at the motor end plate. This interface between the muscle and nerve cells releases a chemical signal, acetylcholine, which tells the muscle fiber to contract. This message is distributed to all the cells in the fiber connected to the nerve.
This signal causes the myosin proteins to grab onto the actin filaments around them. These are the purple proteins in the image below. Myosin uses ATP as an energy source to crawl along the green filament, actin. As you can see, the many small heads of the myosin fibers crawling along the actin filaments effectively shortens the length of each muscle cell. The cells, which are connected end-to-end in a long fibers, contract at the same time and shorten the whole fiber. When a signal is sent to an entire muscle or group of muscles, the resulting contraction results in movement or force being applied.
A muscle can be used in many different ways throughout the body. A certain muscle might contract rarely with a lot of force, whereas a different muscle will contract continually with minimal force. Animals have developed a plethora of uses for the forces a muscle can create. Muscles have evolved for flying, swimming, and running. They have also evolved to be pumps used in the circulatory and digestive systems. The heart is a specialized muscle, which is uses exclusively for pumping blood throughout the body. These different types of muscle will be discussed below.
Types of Muscle
Skeletal Muscle
When you think of a muscle, most people generally think of a skeletal muscle. The biceps, triceps, and quadriceps are all common names for muscles that body builders tend to focus on. In fact, these general muscles are often composed of many small muscles that attach to different places to give a joint its full range of motion. Skeletal muscle is a striated muscle. This means that each muscle fiber has striations, or linear marks, which can be seen when this muscle is put under a microscope. The striations correspond to the sarcomeres present in striated muscles, which are highly organized bundles of muscle cells which can contract quickly in concert.
Skeletal muscle is controlled via the somatic nervous system, also known as the voluntary nervous system. Point your finger to the ceiling. This is your somatic nervous system in action, controlling your skeletal muscles.
Cardiac Muscle
Cardiac muscle, while similar to skeletal muscle in some ways, is connected to the autonomous nervous system. This system controls vital organs such as the heart and lungs and allows us to not have to focus on pumping our heart each time it needs to beat. While there is a certain amount of conscience control we have over the autonomous nervous system, it will always kick in when we are unconscious. For instance, you can hold your breath if you like but you do not have to remember to breathe all the time. Cardiac muscle surround the chambers of the heart and is used to pump blood through the body.
Cardiac muscle is similar to skeletal muscle in that it is striated. Unlike skeletal muscle, cardiac muscle fibers are arranged in a branching pattern instead of a linear pattern. Both skeletal muscle and cardiac muscle need to contract quickly and often, which is why the striations can be seen.
Smooth Muscle
Unlike skeletal and cardiac muscle, smooth muscle is not striated. This is because the individual muscle cells are not perfectly aligned into sarcomeres. Instead, they are displaced throughout the fibers. This gives smooth muscle the ability to contract for longer, although the contraction happens more slowly. Consider the muscle that contracts the sphincter on your bladder. This muscle may need to stay clamped shut for hours at a time and only gets a minute of relief when you go to the bathroom. Many other smooth muscles operate in the same manner.
Like cardiac muscle, smooth muscle is mostly controlled by the autonomous nervous system. The many muscles that line your digestive tract work together to move food through the digestive system. Muscles attach to your hair follicles that all your hairs to stand up when it’s cold. Smooth muscle is almost everywhere in your body and aids in everything from circulation to digestion.
Quiz
1. A big, strong bear goes in a cave to hibernate for winter. In the spring a skinny, weak bear emerges. What happened to the bear’s muscles? A. They stayed the same size, they were just hidden under fat B. The bear used them as energy during hibernation C. The bear’s fur is thinner, making him look weaker
Answer to Question #1
B is correct. Muscles that aren’t being used are wasted energy. The bear will use the protein and nutrients available in its muscle and fat cells to survive through the winter. Some muscles, like the diaphragm used to control breathing, will not see a loss in mass. Other muscles, like the leg muscles, are not needed during hibernation and will be allowed to atrophy, or decrease in size.
2. Growing muscles is known as hypertrophy. Body builders do this when they work out to increase the size of their muscle. Often, days after a good workout, the muscle that got worked will hurt slightly. What causes this? A. Lactic Acid buildup B. Not enough Protein! C. Microscopic tears in the muscle fibers
Answer to Question #2
C is correct. When you really push your muscles to the limits, they begin to tear. If you try to lift too much weight, you will tear you muscles in half. By doing repetitive sets of a heavy weight, a muscle will obtain tiny tears in various muscle fibers. When these tears heal, more muscle cells are used and the overall mass and size of the muscle increase.XX
3. Endurance runners are told to eat pasta the night before a big run. Why is this helpful? A. Pasta doesn’t slosh around while you are running B. Carbohydrates help you soak up more water, which helps you run C. Carbohydrates break down easily and load your cells with ATP
Answer to Question #3
C is correct. The carbs found in pasta can easily be broken down into glucose, which muscle cells convert to ATP to store energy. This ATP is then used to activate the myosin heads and help them walk along the actin filament. In reality, any balanced meal will load your cells up with glucose and prepare you for exercise.
References
Lodish, H., Berk, A., Kaiser, C. A., Krieger, M., Scott, M. P., Bretscher, A., . . . Matsudaira, P. (2008). Molecular Cell Biology 6th. ed. New York: W.H. Freeman and Company.
Nelson, D. L., & Cox, M. M. (2008). Principles of Biochemistry. New York: W.H. Freeman and Company.
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