Brianna Laplante

Well, since this is my last blog, I decided to write about the super versatile liver.  All throughout A&P II, the liver has been involved in just about every system, and serves many functions throughout our bodies.  The liver is one of the bodies largest and most important organs.  It is very resilient, but it isn’t indestructible.  Everything we eat, drink, breath and absorb through our skin will reach our livers.  I think we already know the key objectives about the liver, therefore, Im gonna share ways to keep our super organ healthy!

1)Only drink alcohol in moderation, if at all (1 or 2 drinks a day over many years is enough to cause cirrhosis!!)

2)Don’t mix other drugs with alcohol (tylenol, etc. can be toxic to the liver even if you drink in moderation.)

3)Get vaccinated for hepatitis B!!

4)Use medications wisely

5)Beware of certain supplements (some herbal supplements are toxic to liver, along with high doses of vitamin A, D and E. 

6)Be careful around toxic chemicals.  (even aerosols)  Be in a well-ventilated room, or wear a mask, toxins can harm the liver.

7)Don’t eat too many fatty foods.  Our livers make all the cholesterol our bodies need.  Eating a well-balanced diet will help the liver function properly.

8)Watch weight and exercise

Well everyone, A&P II was very interesting, I learned a lot…(even more than I thought by brain could take at times haha)…but its been great! Have a great summer break everyone!!!

Glycogen is a polysaccharide of glucose, which functions as the primary short term energy storage in animal cells.  It is made primarily by the liver and the muscles.  Glycogen is found in the form of granules in the cytosol in many cell types, and plays an important role in the glucose cycle.  Glycogen forms an energy reserve that can be quickly be mobilized to meet a sudden need for glucose.  In the liver hepatocytes, glycogen can account for up to 8% of the fresh weight after a meal.  Only the glycogen that is stored in the liver can be used by other organs.  Glycogen is found in muscles at a much lower concentration.  Small amounts of glycogen are found in the kidneys, and even smaller amounts are found in certain glial cells in the brain and white blood cells.  The uterus stores glycogen during pregnancy to nourish the embryo.  Glycogen is broken down when ATP is needed by muscle cells or when blood glucose levels drop too low.  Glycogen synthesis and breakdown is under hormonal control. 

We get glycogen from carbohydrates, natural sugars (fruits, veggies, milk), and complex carbs (grains, cereal, pasta).   

I remembered that cerebral palsy was brought up in class a couple of times.  I was unsure of what this condition was all about…so I did some further research.  Cererbral palsy is a disorder that affects muscle tone, movement and motor skills.  Even simple movements such as standing can be difficult for those with cerebral palsy.  Other vital functions such as breathing, bladder and bowel control, eating and learning are also affected when a child has cerebral palsy.  Cerebral palsy can also lead to other health issues including vision, hearing and speech problems and learning disabilities. 

Cerebral Palsy is usually caused by brain damage that occurs before or during a child’s birth, or during the first 3-5 years of a child’s life.  Cerebral palsy is one of the most common congenital disorders of childhood.  About 500,000 children and adults of all ages have this condition. 

There are 3 types of cerebral palsy:

1) static cerebral palsy-causes stiffness and moving difficulties

2)athetoid cerebral palsy-leads to involuntary and uncontrolled movements

3)ataxic cerebral palsy-causes a disturbed sense of balance and depth perception

There is no cure for cerebral palsy, but treatment, therapy, special equipment and in some cases surgery can help those living with this condition.  Cerebral palsy does not get worse over time. 

Excretion is the process of eliminating waste products of metabolism and other non-useful materials.  It is an essential process in all forms of life.  The process of excretion involves finding and removing waste products from the body.  The excretory system regulates the amount of water and ions present in body fluids. 

The primary organs of excretion are the lungs, liver kidneys and skin.   Waste products gases are carried by blood traveling through veins to the lungs where respiration takes place.  Dead cells and sweat are removed from the body through the skin.  Liquid waste is removed from the body through the kidneys.  During circulation, blood passes through the kidneys to deposit used and unwanted minerals, water, and a nitrogen-rich material called urea.  The kidneys filter waste from the blood, forming urine.  The kidneys funnel the urine into the bladder along 2 seperate tubes called ureters.  The bladder stores the urine until muscular contractions force the urine out of the body through the urethra.  Feces are expelled through the large intestine.  In strict biological terminology, the removal of fecal material is not considered excretion because feces are indigestible foods and they are not metabolic waste.  Removing digestive wastes is done through a process called egestion. 

 The 4 types of metabolic wastes in the human body are water, carbon dioxide, salts and urea. 

*Water is a by-product of dehydration synthesis and respiration

*Carbon dioxide is a by-product of cellular respiration

*Salts are a by-product of neutralization

*Urea is a by-product of protein metabolism, deamination

We expend energy no matter what we are doing, even when sleeping.  The Basal Metablic Rate (BMR) is the number of calories one would burn if they would stay in bed all day.  If you’ve noticed that every year it gets harder and harder to eat whatever you want and stay slim, its because our basal metabolic rates decrease as we age.  When someone deprives themselves of food, their BMR decreases, losing hope of shedding pounds.   However, a regular routine of cardiovascular exercise  can increase BMR, improving health and fitness when the body’s ability to burn energy gradually slows down. 

 If you guys are interested in calculating your basal metabolic rates…check out this website…

http://www.blaha.net/Main%20BMR%20Calculator.php

Factors that influence BMR are age, gender, weight, height, environmental temperature, dieting and exercise habits.  Males have a greater percentage of lean muscle in their body, therefore, they have a BMR that is generally 10-15% faster than women.  An accurate BMR reading requires that a person’s sympathetic nervous system is not stimulated. 

Metabolism is a collection of chemical reactions that takes place in the body’s cells.  Metabolism converts the fuel in the food we eat into the energy needed to power everything we do–from moving, to thinking, to growing.  If metabolism stops, living things die. 

After food is eaten, enzymes in the digestive system break down proteins into amino acids, break down fats into fatty acids and carbohydrates into simple sugars (glucose).  Along with sugar, amino acids and fatty acids can be used as energy sources by the body when needed.  These compounds are absorbed into the blood, which transports them to cells. 

After they enter the cells, other enzymes act to speed up chemical reactions involved with “metabolizing” these compounds.  During these processes, the energy from these compounds can be released for use by the body, or stored in body tissues–especially the liver, muscles and body fat.  In this way, the process of metabolism is really a balancing act involving 2 kinds of activities that go on at the same time–the building up of body tissues/energy stores and the breaking down of body tissues/energy stores to generate more fuel for body functions. 

Anabolism: constructive metabolism

Catabolism: destructive metabolism

Metabolism is a complicated chemical process in the body.  Basal metabolic rate, calorie intake, and hormones are just a few factors that influence metabolism!!  Just like a car stores gas in the tank, the body stores calories–primarily as fat.  If you overfill a car with gas it will spill onto the tar.  Likewise, if you fill the body up with too many calories..they will form excess body fat!

I have a close friends who has Crohn’s disease, so after last night’s lecture on digestion, I realized Crohn’s fits right into the discussion.  Crohn’s disease is an ongoing disorder that causes inflammation of the digestive tract.  Crohn’s can affect any part of the GI tract from the mouth to the anus, but most often, it affects the ilium.  The swelling extends deep into the lining of the affected organ.  The swelling can cause pain and can make the intestines empty frequently, resulting in diarrhea.  Crohn’s disease is an inflammatory bowel disease, the general name for diseases that cause swelling of the intestines. 

The symptoms of Crohn’s disease are very similar to colitis and irritable bowel syndrome, making it often-times difficult for a diagnosis.  Symptoms of Crohn’s include abdominal pain, diarrhea, rectal bleeding and weight loss.  Treatment options for Crohn’s include the use of anti-inflammatory drugs, cortisone, steroids, immune system suppressors, infliximab, antibiotics and anti-diarrheal/fluid replacemation therapies.  Two thirds of people living with Crohn’s will need surgery at some point in their lives.  Surgery becomes necessary when medication can no longer control symptoms. 

It is crucial for people living with Crohn’s disease to follow a nutritious diet and to avoid foods that worsen symptoms.  People with Crohn’s should regularly meet with their physician to keep their condition under control to their best ability.  Although the cause of Crohn’s disease is unknown, it is believed to be an autoimmune disease that is genetically linked!!   Have a great week everyone, enjoy the nice weather! 

Digestion is the process in which the body breaks down food into smaller components that can be absorbed into the blood stream.  In mammals, preparation for digestion begins with the cephalic phase when saliva is produced in the mouth and digestive enzymes are produced in the stomach.  Mechanical and chemical digestion begin in the mouth where food is chewed and mixed with saliva to break down starches.  The stomach continues to break down food mechanically and chemically through the churning of the stomach mixing with enzymes.  Absorption occurs in the stomach and gastrointestinal tract, which finishes with excretion.  Levels of pH play an important role in proper digestion. 

The 4 seperate stages of digestions include:

1-Ingestion: placing food into the mouth

2-Mechanical and Chemical Digestion: mastication to tear and crush the food, and churning of the stomach.  Addition of chemicals such as bile, acid, enzymes and water to break down complex molecules into simple structures

3-Absorption: moving the nutrients from the digestive system to the circulatory and lymphatic capillaries through osmosis, active transport and diffusion

4-Egestion: removal of undigested materials from the digestive tract through defecation

Digestion is a pretty complicated process, think of how amazing our bodies are to be able to break down all the different foods we eat on a daily basis!! The human body is incredible! Have a good week everyone!! Enjoy the beautiful weather!