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Quick Links
Information for newcomers to learn about the facinating craft of Beekeeping in Getting Started.
Practical advice on many aspects of Beekeeping in our Knowledge Centre.
Ther latest reports from the SBKA President and other Officers.
Information about the shows at which the SBKA will be represented; come along and see us at these upcoming events.
For our members, read the latest news letters and press releases.
Find out who's who in our Divisions.
Contact our webmaster to comment on or contribute to our website.
Journey Through a Bee
Introduction
The journey of food through a bee from mouth to anus is necessary in order that large molecules of food, which are too big to pass through the gut wall, can be chemically broken down into their smaller units which are then easily able to diffuse into the blood. This process is called DIGESTION and is brought about by digestive ENZYMES.
Nectar
Nectar (see figure below) contains, on average, about 20% sugars. Of these, glucose and fructose, being single sugar units, are small enough to pass into the blood. But sucrose (cane sugar), being composed of glucose and fructose chemically joined together, needs to be digested so that these two simple sugars can be liberated, and so made available to provide the bee with the ENERGY it requires.
Pollen
Pollen (see below) contains the protein which is needed for the GROWTH of the larvae and is eaten by the house bees which are making the brood food. It too has to be digested by enzymes into its smaller units called AMINO ACIDS, so that it can be absorbed into the blood. The blood takes the amino acids to the hypopharyngeal glands where the brood food for the larvae is made.
The Gut or Alimentary Canal
When gathering nectar the proboscis is extended, nectar is sucked up and, after being swallowed, it reaches the crop.
The Crop of Honey Stomach
This is capable of great distension and the bee can carry over half her own weight of nectar. In this way a substantial volume of nectar is brought back to the hive. During the journey home the nectar is stirred and mixed with the enzyme SUCRASE which starts the conversion of sucrose into glucose and fructose. Thus, when the bee reaches the hive, there is a higher proportion of these two simple sugars than there was when she first sucked up the nectar. This is regurgitated to the house bees and any required by the forager passes through to the proventriculus.
The Proventiculcus
This projects into the crop and acts as a valve or a plug. It helps to stir the crop contents, but its main function is to filter out the pollen. The filtering is carried out by means of its four triangular lips fringed with hairs. The pollen is then passed backwards into pouches beneath the lips. When these are full the pouches are emptied and the pollen enters the ventriculus.
Ventriculus
This is a large, wide structure which keeps the food for 12 - 24 hrs. so that the protein in the pollen can be thoroughly digested into AMINO ACIDS. The cells producing the enzyme "bud off" from the inside wall of the ventriculus. They then burst open; the enzymes are released, and enter the pollen through pores in the husk.
Intestine
Here the digested food, i.e. glucose, fructose and amino acids, is absorbed into the blood. The wall of the intestine has six longitudinal folds to increase the surface area for absorption.
Rectum
This contains waste products, mainly pollen husks and remains of gut cells. It is capable of great distension. This is important in winter bees when the weather is cold and they are unable to leave the hive to make cleansing flights.
"Journey through a bee" Copyright J.LTucker 2005.
