How spiders breathe

When incey wincey spider climbed up the water spout – it was probably to get some air because spiders need to breathe just like us.

When incy wincy spider climbed up the water spout.Original pic by Derek Law 

 

Spiders exchange gases (breathe) in a similar way to insects. We’ve looked at insect breathing in a previous blog post – but here’s a quick recap.  Spiders (and insects) have tiny holes in their abdomen called spiracles.  Each spiracle is an opening to a tube called a trachea.   Oxygen from the environment travels directly down the system of trachea to each cell (and the carbon dioxide waste returns the same way to the environment).

 

Some spiders also have extra breathing organs that insects don’t have.  These organs are called book lungs, because they sort of look like pages from a book.  Spiders can have either one or two pairs of book lungs.  The “pages” of the book lung are called lamellae.  When the spider moves, air passes over the large surface area of the lamellae and oxygen can be absorbed into the spiders’ blood.

Spider internal anatomy – look for the book lungs (in pink) Diagram from Wikipedia

Spider blood is called haemolymph and unlike our blood is blue.  Our red blood gets its colour from haemoglobin which contains iron (the red bit).  Haemoglobin is the protein that carries oxygen around our body.  Spiders (and many other arthropods and also molluscs) have a different protein to carry oxygen called haemocyanin.  Haemocyanin contains copper instead of iron which gives it a blue colour.

Close up drawing of Spider book lungs. (1) the lung slit that opens outside the spiders body, (2) space filled with hemolymph, (3) the horizontal lamellae look like pages from a book. From Wikimedia Commons

Most spiders have both trachea and book lungs.  Some species only have trachea and some only book lungs.  Small spiders that live in dry habitats like deserts need to be careful not to lose water across the trachea (or book lungs).  These spiders rely on diffusion of oxygen and carbon dioxide across their skin and don’t have any breathing organs where water could be lost.

Friday 5: Bugs with Bubbles

Check out this great blog post with gorgeous photos of amazing bugs that can extend the time they spend underwater by carrying bubbles of air with them

The bends – decompression sickness

One of my friends got the bends recently after SCUBA diving to 40 metres.  He’s been told he can’t dive any longer (which really sucks for him) because he now has a much higher risk of getting the bends a second time.  But what exactly is the bends (apart from an awesome Radiohead song)?

2012 in review

The WordPress.com stats helper monkeys prepared a 2012 annual report for this blog.  7500 views……awesome!  Thanks for reading guys, and here’s to 2013!

Here’s an excerpt:

600 people reached the top of Mt. Everest in 2012. This blog got about 7,500 views in 2012. If every person who reached the top of Mt. Everest viewed this blog, it would have taken 13 years to get that many views.

Click here to see the complete report.

Chloroform breathing bacteria

In the movies, chloroform is what the villain pours onto a rag and stuffs into the face of the hero.  After some flailing of limbs, the hero passes out and is bundled into a white van and taken away to the villain’s secret lair.

Chloroform is a sweet-smelling liquid.  It is a natural product of many seaweeds and has been synthesised in the laboratory as early as 1831.   In the 1850s, chloroform was used as an anaesthetic.   Chloroform vapour depresses the central nervous system.  The only problem is that it is highly toxic and carcinogenic (cancer-causing).   The high number of deaths caused by chloroform anaesthesia resulted in the practice being abandoned.

A new bacterium (Dehalobacter) has been discovered in the sediment in Port Botany, Australia that breathes in chloroform and breathes out acetate (very close to vinegar), hydrogen and carbon dioxide.

Chloroform breathing bacteria may one day help clean up toxic waste.
This great photo is courtesy of Adam Cohn. Check out this photo on his Flickr

Why don’t birds breathe like the rest of us?

Birds breathe quite differently to us.  They don’t have a diaphragm and their ribs only move slightly when they breathe in.  Instead they use large air sacs like bellows to move air through their lungs.  It takes two full breaths for air to move through the lung system of a bird.

 

It takes two full inhalation-exhalation cycles for a specific volume of air (blue) to pass through bird lungs.
Adapted from Bretz and Schmidt-Nielson, 1972

Do plants breathe?

Well, we know that plants produce the oxygen that we breathe in…..photosynthesis right?  And we’ve previously explored how we use oxygen in a process called cellular respiration where we create ATP, the energy currency of the cell.  This currency lets us do pretty much everything we need to do like growing, moving and reproducing (if and when we get around to that!).  Surely if the ATP (cash moneys) is needed to fund all these processes in us, then plants, which also grow and reproduce are going to need some too, right?  Right!

Even plants “breathe”
This photo was taken by Sarz AA. All rights reserved. Check out her Flickr for more photos (and legal stuff).

Can you stop breathing? Frogs can………for winter

Things are dead if they stop breathing right?  How about if their heart stops?  I think I’d be pretty dead if my heart and breathing stopped for too long, in fact humans have only got about 4 minutes to be resuscitated if their heart stops.  Without breathing to bring in fresh oxygen and get rid of carbon dioxide, and without the heart to pump these gases around the body, the brain becomes hypoxic (lack of oxygen) and can’t survive.  Amazingly, some frogs can survive the winter without breathing!

This fantastic fellow (wood frog, Rana sylvatica) was photographed by Dave Huth. Some rights are reserved. Check out his Flickr for more photos (and legal stuff).

How deep can a human dive? New footage of freediver Guillaume Néry at NEMO 33

The interwebs are awash today with new footage of the past world-record holding, free-diver Guillaume Néry plunging to the of the world’s deepest swimming pool.  The NEMO 33 in Brussels, Belgium is unsurprisingly 33 metres deep and contains an unfathomable 2.5 million litres of non-chlorinated spring water.  It’s mostly used to train divers and even has simulated caves at 10 meters.

Insects and Plants Use the Same Strategy for Breathing Underwater

Check out this great article on insects and plants breathing underwater!

Insects and Plants Use the Same Strategy for Breathing Underwater.