• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Function of the Golgi Body.

Extracts from this document...


Function of the Golgi Body P1 The golgi body, also known as golgi apparatus or golgi complex. It is a network of stacked sacs found within nucleated cells. The golgi body stores, packages and distributes the proteins and lipids made in the endoplasmic reticulum. Proteins, which are meant to return to the endoplasmic reticulum, carry a distinctive tag. The golgi apparatus recognises the tag and transports the proteins back to the endoplasmic reticulum. However some proteins and lipids are sent to the surface of the cell to be released into the external environment. Structure and Function of Epithelial Tissues P2 Structure: The epithelial tissue is the layer of cells covering the outside of organs and the skin. These types of cells are firmly attached to each other and rest on a basement membrane, they also have a free surface. There are many different types of epithelial tissue all depending on how many layers and the shape of the individual cells. 1. Simple Epithelium - has only one layer of cells. It can either be : * Squamous - which are thin and flat. (1) * Cuboidal - these are cube shaped with a central spherical nucleus. ...read more.


The gallbladder is a muscular organ, which is a membranous sac often pear-shaped. It is found on the under-surface of the right lobe of the liver. Functions of the liver The liver has many functions including: * Digestive functions Digestive functions are carried out by bile, which is produced in the liver. * Metabolic functions The liver is very important for homeostasis because it directly determines the concentration of many different substances in the blood plasma. These activities are called metabolic or regulatory functions, these include: * Regulation of blood glucose * Regulation of lipids * Regulation of aminoacids * Regulation of plasma proteins * Storage of vitamins and minerals * Production of heat * Storage of blood * Excretory functions Excretion is the removal from the body of the waste products of the metabolism and of substances surplus to the body's requirements. * Production of urea Urea can only be formed in the liver, if ammonia is left to accumulate in the blood it will cause problems. * Break down of blood cells Red blood cells are continually being produced in the bone marrow and have a life spa of 129 days. ...read more.


The amount of glycogen formed is controlled by a hormone called insulin, this is produced by the pancreas. This hormone acts mainly by prompting the uptake of glucose by the membranes of the liver and muscle cells. In the human liver up to 60g of glucose can be stored in the form of glycogen and 150g in the muscles. Once this limit has been reached, excess glucose is converted into molecules of fat, which then leave the liver through the vein and are taken up for storage by adipose cells, mostly under the skin. The process of glycongenolysis is controlled by two hormones, glucagon from the pancreas and adrenalin form the adrenal glands. They are released in response to a fall in blood glucose but adrenalin can also be produced in times of stress so it boosts the availability of glucose quickly. * When animals have not eaten for several hours, hepatic glycogen reserves become exhausted. The hepatocytes recognise the problem and activate other enzymes to start synthesising glucose out of other substances, like fats or amino acids, if the fasting is prolonged. This process is known as gluconeogenesis, and it is controlled by the hormone glucagon. The ability of the liver to synthesise glucose this way is greatly important to carnivores, whose diet in the wild has virtually no starch. 1 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Exchange, Transport & Reproduction section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Exchange, Transport & Reproduction essays

  1. Marked by a teacher

    Human Reproductive System

    4 star(s)

    The secondary oocyte is covered by: the corona radiata and the zona pellucida. The sperm penetrates these layers through capacitation, which involves the stimulation of acrosome reaction. The acrosome present in the head of the sperm secretes digestive enzymes that break down these layers and the sperm penetrates into the oocyte.

  2. The Skeletal and Muscular System

    Muscles, bones and joints provide the mechanics for the movement of the body. 3. Support. The skeleton provides a structural framework to the body. It supports the body and maintains its shape by supporting soft tissues and providing attachment point for the tendons of most skeletal muscles.

  1. Blood System Assignemnt

    Explain the problem that can occur when transfusing blood. Although blood looks like a red liquid, if some is left in a test tube it separates out into pale liquid called plasma and a solid layer of blood cells. Major components of blood -made up of the following things: Plasma - Blood cells are suspended in the plasma.

  2. The Endocrine System

    Growth Hormone (GH), also known as Somatrophin, is produced and secreted from the anterior pituitary gland. The functions of GH are protein synthesis, growth of tissues, but particularly bones of limbs. GH deficiency can be caused by tumours, infection, head injury or irradiation of the pituitary.

  1. permeability of beetroot membranes

    g 3.49 g 2.91 g 0.20 M 0.60 g 3.78 g 3.18 g 0.00 M 0.60 g 3.88 g 3.28 g These are the weights of the potato disks after 24 hours in the glucose solutions.

  2. AN ACCOUNT OF NITROGENOUS EXCRETION IN MAMMALS Excretion is the disposal of the waste ...

    Uric acid is a much larger molecule than urea. It is a purine, similar in structure to adenine and guanine. Energy from metabolism is required in the formation of uric acid, but once formed it is virtually insoluble and therefore non-toxic to the organism. Uric acid is produced as a colloidal suspension.

  1. Regulation and Control Homeostasis.

    * The organic residue enters the Krebs cycle and is respired. * Ammonia is converted to the less harmful substance urea, which is excreted. * Transamination reactions, whereby one amino acid is converted to another, are also carried out by the liver i.e.

  2. Revision questions on Communication, Homeostasis and Energy

    of the neurone, which causes sodium ion channels to open further along the membrane. * The concentration of sodium ions rises where the sodium ion channels are open. * So sodium ions diffuse sideways away from the increased concentration. * When the potential difference across the membrane has decreased, gates

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work