Posts Tagged ‘cholesterol’

Functions of the liver

Thursday, March 25th, 2010
BIO 120 Liver 010 by djneight on flickr

BIO 120 Liver 010 by djneight on flickr

Here are a couple of presentations for you. Functions of the liver  and this one.  You should be able to:

  • Outline the circulation of blood through liver tissue, including the hepatic artery, hepatic portal vein, sinusoids and hepatic vein.
  • Explain the role of the liver in regulating levels of nutrients in the blood.
  • Outline the role of the liver in the storage of nutrients, including carbohydrate, iron, vitamin A and vitamin D.
  • State that the liver synthesizes plasma proteins and cholesterol.
  • State that the liver has role in detoxification.
  • Describe the process of erythrocyte and hemoglobin breakdown in the liver, including phagocytosis, digestion of globin and bile pigment formation.
  • Explain the liver damage caused by excessive alcohol consumption.

Cell membrane structure

Monday, November 16th, 2009
Simple diffusion in cell membrane from wikimedia commons

Simple diffusion in cell membrane from wikimedia commons

Some questions to tackle this week:-

  • Do you know what a phospholipid is? 
  • Can you draw a labelled diagram of a cell membrane?
  • What other structures are present in the membrane to help it perform its function of allowing substances into and out of cells?
  • How does this relate to diffusion?
  • Can you explain why the membrane is described as fluid?

Here are some links to images and animations that might help you understand the answers to these questions.

Simple diagram of cell membrane.  More complex diagram of cell membrane.

Animation showing that the cell membrane is selectively permeable by only allowing molecules that are small enough to pass across.

This animation shows how protein channels can help diffusion of larger molecules across the membrane.

This interactive animation explains diffusion and how it relates to membrane structure.