Bio quiz on Liver and Kidneys

You will be having a short quiz on the Kidneys and Liver in two classes. If, for any reason, I am absent, you are still responsible for COMPLETING ALL WORK - notes, quizzes, etc. There is no reason that you should not be making an effort to complete all assignments in class, as you will be given adequate time. If I am not at school for your class, you can send me an e-mail at misshampson(at)gmail(dot)com, or find me the next day! If you do have any problems, please e-mail me as soon as possible, so that I can respond to your needs. Thanks!

314-05
Monday (Day 5): Review Kidneys, Discuss liver, take notes, complete questions on liver
Thursday (Day 8): Review liver and kidneys, answer any questions, QUICK QUIZ!

314-08
Wednesday (Day 7): Review Kidneys, Discuss liver, take notes, complete questions on liver
Friday (Day 9): Review liver and kidneys, answer any questions, QUICK QUIZ!

Notes on the liver and kidneys:
In the textbook, this section is located beginning on page 201.

Kidneys

Humans have a right and a left kidney, which are small, oval organs lying to either side of the spine. They are protected in the back by the muscles.

The primary function of the kidneys is to filter metabolic waste products. This means that when the body is processing food and nutrients to get energy, waste is produced. Quick review: What is produced as a result of the metabolism of lipids? Carbs? Protein?

The kidneys also filter sodium (salt) and water from the blood, and help eliminate them from the body. This is done through by filtering them out.

Each kidney is supplied with blood by a large renal (kidney) artery, a direct branch off the aorta (Remember: this is an artery that supplys blood to the upper part of the body.) In healthy adults, the two kidneys together receive approximately 20% of the blood pumped by the heart. This means each kidney receives one litre (HALF of a big bottle of Coke :) EvErY MiNuTe!

The kidneys contain tiny filtering units. The blood passes through the capillaries (the smallest blood vessel), and the water is forced out. The cells and protein in the blood are too big to pass outside of the capillaries, so, only the waste is able to pass out. The filtering begins in a part of
the kidney called the cortex.

The waste then drains through the ureter (the tube that carries urine, also known as pee) and empties into the bladder. The bladder, when it is full, is what makes you feel like you have to go to the bathroom. The bladder is drained through a tube called the urethra, and this is the process of urination (peeing).

The filtering action of the kidneys is designed so that the salt and water that the body needs, it is able to hold on to. The waste product urea (produced by the metabolism of protein) is able to be disposed of.

Red blood cell production
The kidneys have other discrete functions, including control over how often red blood cells are produced.

Vitamin D production
Another function of the kidneys is to activate vitamin D. Vitamin D is derived from the diet or the effects of sunlight on the skin, but has to be converted to a final active product in the kidneys. If the kidneys can no longer perform this function, symptoms such as bone disease with bone pain or fracturing can occur.

The Liver
The liver plays a major role in metabolism. It also produces bile, which is important for digestion. Medical terms related to the liver often start in hepato- or hepatic from the Greek word for liver, hepar.

The adult human liver normally weighs between 1.0 - 2.5 kilograms, and is a soft, pinkish-brown "boomerang shaped" organ. It is the second largest organ (the largest organ is actually the skin!) It is located underneath the diaphragm, in the upper abdomen. The gallbladder stores bile used in digestion.

The liver processes the nutrients and byproducts of food digestion. The bile produced in the liver is collected in bile ducts. Bile drains directly into the duodenum, or can be temporarily stored in the gallbladder.

The liver is one of the only internal human organs able to regenerate (grow itself); as little as 25% of remaining liver can regenerate into a whole liver again.