The Anatomy of bee’s, and the environment of fish (Day 177)

Bee sting showing barbs under the electron microscope

Today’s Diary Entry is sponsored by Spikes World

What a day, to be honest I am sitting here wondering how I could possibly fit it all into my 500 word daily target. It’s a shame really that I have 3 subjects that I could talk about for hours in a single day and other days where I am really left with not much to say at all. I am actually considering splitting my diary for Tuesdays over both Tuesday and Thursday which will let me go into more  depth, and give me more to talk about Thursdays – what do you guys think of this?

Well today started with diseases of bee’s, and the major part of it went to look at the difference in anatomy of bee’s. Now this is pretty interesting as the bee is so small yet has several differences, the first of which is that it has an open circulatory system. Basically instead of having capillaries to carry the blood to organs the heart pumps it directly into body cavities to surround organs before it then diffuses back to the circulatory system. In fact even bee blood itself is different as the bee does not have erythrocytes (red blood cells); instead it has something known as haemolymph which is made up of haemocytes and is a yellowish colour. The bee also has several specialised glands which help produce the honey and wax, in addition to the poison gland which is located next to the stinger.

It’s pretty common knowledge that a bee with die after it stings you, whats not so common is the understanding of why this is. Below you can see an image of the bee sting under the electron microscope and see that it has barbs each side which hook into the skin when a bee stings you. Now these means it takes time for the bee to remove it after however our first instinct is the brush the bee of us, and when we do this the stinger and attached poison glands are ripped from the bee’s abdomen causing its death.

Bee sting showing barbs under the electron microscope
Bee sting showing barbs under the electron microscope (via http://www5.pbrc.hawaii.edu/microangela/bsting.htm)

Onto fish now today we started looking at the effect of the environmental conditions on the fish. Now the environment includes both the physical and chemical characteristics of the water that is home to the fish. Whether that is the temperature, viscosity, density, pH, salinity, oxygen saturation or even the electric conductivity.Today I will look at the oxygen in terms of the environmental conditions as without it there is no life. Fish take oxygen dissolved within the water into their body through the gills where it then enters the blood. Now the temperature of the water does really affect the level of oxygen that can be saturated within the water (the graph below is for an indication only and does not have a complete dataset!).

Oxygen saturation vs the temperature of the water
This chart is produced from an incomplete dataset, consult other sources for full values!

As you can see water at 100 degrees celsius cannot contain oxygen, ideally most fish live in conditions with the temperature between 15 – 30 degrees celsius. Now oxygen enters waters through two routes, the diffusion of oxygen from the water/air barrier at the surface, and through the process of photosynthesis. The majority of oxygen in water does actually come from photosynthesis of plant matter, this requires sunlight so on average there is 12 hours where photosynthesis does not take place. This leads us into a daily cycle of variation in the oxygen concentration with the oxygen level in water being lowest just before dawn, and highest at sunset.

During winter when the days are shorter (so less light), and with many water areas being frozen (preventing the diffusion of oxygen into the water) many fish enter a low metabolic state (aka use less oxygen to live) in the bottom layer of the water. During this period of low energy fish are extremely vulnerable to disease. On that note I will leave you for today!

Inside the Bee hive with honey bee’s and an introduction to Diseases of Fish (Day 163)

Vet School Puffer Fish - Diseases of fish

Today’s Diary Entry is sponsored by Pet Webinars

Well today started with Diseases of Bee’s which has a excellent lecturer, we moved to a new larger classroom today and were greeted by a beehive (minus the bee’s!). The modern beehive is generally a wooden box with a loose lid and loose base which can be easily stack-able. Inside this box there are frames held vertically with a honeycomb lining made from wax like this…

Beehive wax honeycombe frame vet school
Honeycomb frame from a beehive

Worker bee’s produce two products, honey, and beeswax (which is what the honeycomb framework is made from). The honey is stored within the cells in the wax honeycomb with the bee’s sealing the entrance to the cell with a layer of wax as in the picture below.

Vet School honeycomb frame with honey in sealed wax cells
Honeycomb with honey in sealed cells

The honeycomb is also important for the production of new bee’s as the queen bee will lay her eggs in the cells (one egg to one cell). To understand this I should probably explain how the colony is organised. There are 3 types of bee’s within a colony:

  • Queen – Each colony only has a single queen that usually lives 3 – 5 years and is responsible for laying egg’s, and in addition to ensuring that no other queen females reach adulthood. The queen is diploid.
  • Worker Bee’s – These are the females in the colony and perform the function of harvesting pollen, building the honeycomb and creating the honey These are also diploid in terms of genetics.
  • Drone Bee’s – These are the males in the colony and are responsible for the general housekeeping, fertilising the eggs and looking after the young. These are haploid in terms of genetics and are actually kicked out of the colony at winter!

So the queen bee uses the wax honeycomb to lay eggs which are then sealed with wax by the drone bee’s. The worker bee’s after collecting pollen turn it into honey and fill the cells of the honeycomb with it sealing it in. The production (or reproduction) of bee’s is something I will look at more next time I write about bee’s as I must get onto some fish now!

This was followed by Diseases of Fish, this week we continued working our way through the massive taxonomy list of fish species. As I did not introduce this last week I’ll look at some general background. Fish are cold-blooded (the technical term for this is poikilotherms) typically with backbones, gills and fins. Fish make up around 57% of all living animals with around 27,977 species with the smallest being Paedocypris progenetica measuring 7.9mm long, and the largest being the whale shark Rhincodon typus which measures 12m long and weighs 12 tonnes!

Now fish can live in temperatures from -2 degrees Celsius in Antarctic waters through to 40 degrees Celsius in hot springs. They live in areas from 5km above sea level, and as discovered in 2007 through to 25,000 feet deep water (the snailfish).They range from pretty coloured through to the pretty intimidating looking.

Vet School Puffer Fish - Diseases of fish

In terms of the taxonomy. Fish belong to the domain Eukaryota, the kingdom Animalia, subkingdom Eumetazoa, superphylum Deuterostomia, phylum Chordata. Within this there are several different subphylums, superclasses, classes and species which I’ve got to learn for my exam in just 6 weeks time! With that I will leave you until tomorrow!