Thinking Allowed

Check out lottolab.  Watch the TED video and then play around the site.  There are loads of optical illusions to keep you entertained.

And now get back to your mock revision….Friday 19th March is looming!

peacock by vigilant20 on flickr

Here’s what we need to cover in this last section of Option E.

1. Honey bees are social organisms.  Describe the organization of a bee colony – who does what.  Find one other example of such social organization and describe it. #1 2 Social Organisms
2. What is the role of natural selection in colonies like this?
3. Give 2 non-human examples of altruistic behaviour and discuss in terms of evolution.  Altruistic Behavior in animals
4. What is foraging?  Bluegill fish forage for Daphnia.  Find one other example, and explain how this type of behaviour optimizes food intake. E6 notes #3 4
5. Peacocks have pretty fancy tail feathers.  Why have they evolved this way? Explain in terms of mate selection. #5 animal behavior   Peacocks #5
6. Animals show rhythmical variations in activity.  Outline 2 examples illustrating this.  Eg, seasonal reproductive behaviour in deer. Rythmical Variations

Here’s a very useful slideshare presentation on this section.

fMRI by nats on flickr

This next section, E5, is all about the human brain, brain function, fMRI, sympathetic and parasympathetic nervous systems, pupil reflex, brain death, and the perception of pain.  Phew!  That’s a lot of concepts. 

We’ll again use click4biology as a good resource, and this presentation from Mr Taylor in Bandung to help us get through it all.  Here are the key questions we need to answer:

• What are the major parts of the human brain, and what are their functions?
• How do animal experiments, lesions and fMRI scanning used in identifying which part of the brain is involved with specific functions?
• How are heart rate, movements of the iris, and blood flow to the gut controlled by the sympathetic and parasympathetic nervous systems?
• What is the pupil reflex and how is it used to determine brain death?
• How is pain perceived and how to endorphins help to alleviate it?

This is also a very useful set of notes, courtesy of Mr Hobbins. Topic E5 The Brain

Eye see you! by dotbenjamin on flickr

We’ll start by looking at the different kinds of receptors that humans have, then focus on the photoreceptors in the eye and mechanoreceptors in the ear.  Click4biology is useful, as is this presentation by Mr Taylor in Bandung.

You need to be able to label a diagram of the eye like this one: Eye diagram

We’ll also do an eye dissection so you can relate the diagram to “reality”.  We’ll compare the different types of photoreceptors that are on the retina, namely rods and cones.  We’ll explain contra-lateral processing (right brain processing information from left eye, and vice versa). And finally we will explain certain kinds of optical illusions by looking at edge enhancement.

We’ll label a diagram of the ear and explain how sound is perceived.  Here are some questions for consideration:-

Why do we have two ears?  What role does the pinna play in other animals? Can fish hear? What range of sounds can the human ear hear? What is a cochlear implant and how does it work?  What does it mean to be tone deaf or have perfect pitch?

addiction by alancleaver_2000 on flickr

Here are the big questions for us to tackle in this section:

• How does decision-making occur in the CNS?
• How do psychoactive drugs affect the brain and personality?
• What the physiological effects of THC and cocaine?
• What are the causes of addiction?

We’ll use this presentation from Mr Taylor.  And, as usual, click4biology is a great resource.  Also, for fun, check out this site.  You’ll find some very entertaining mice!

Thanks to Mr Hobbins for this powerpoint. E4 Neurotransmitters and Synapses

The syllabus guide for this topic: Option E – syllabus guide

We are starting option E with a look at the nervous system.  Check out this excellent presentation from Mr Taylor.

What are some examples of reflexes that exist in humans?  Are there some that exist in babies but not in adults?  Do other animals have reflexes that we don’t have?  Do plants have reflexes?  What is the purpose of a reflex action? 

Here are some questions we need to answer:

1. What is the difference between innate and learned behaviour?  How can the process of learning improve the chance of survival?  Give examples.
2. What is the difference between taxis and kinesis?  Give examples of each.  How could these be investigated in the lab?
3. What experiments did Pavlov carry out on dogs?  What is the difference between unconditioned and conditioned stimuli?  What is the difference between unconditioned and conditioned response?
4. What role do genetics and learning play in the development of birdsong in young birds?

This presentation from Mr Taylor in Bandung is excellent, as is click4biology.

And we’ll finish this section by doing a design lab – you need to design an experiment to investigate innate behaviour by either taxis or kinesis.  This will just be a design exercise – we won’t actually carry out the lab. Here are the criteria: Design lab criteria

All ears by banlon1964 on flickr

You need to be able to label a diagram of the human ear using the following labels:

• pinna
• eardrum
• bones of middle ear
• oval window
• round window
• semicircular canals
• cochlea
• auditory nerve
• Eustachian tube

This animation explains how sound waves are detected by the ear and transmitted to the brain.

This site is useful in explaining how we hear.

Think about these questions – why do we have two ears?  What role does the pinna play in other animals? Can fish hear? What range of sounds can the human ear hear? What is a cochlear implant and how does it work?  What does it mean to be tone deaf or have perfect pitch?

Mr Gray Eyes by Tim in sanhazzay on flickr

Here is the syllabus guide for this topic. Option E – syllabus guide

We’ll be using notes and resources from click4biology.

The first section is all about stimulus and response, so we’ll recap a bit of the nervous system, particularly the stuff on reflex arcs.  We’ll then move on to explain how animal responses can be affected by natural selection.  You need to investigate two examples of this.  Use can use the blackcap bird (Sylvia atricapilla) as one, and any other of your choosing.

Moving on to perception of stimuli, we’ll study both the eye and the ear.  You need to be able to label a diagram like this one: Eye diagram  We’ll then do a dissection so you can identify the parts properly.

You will also have to:

• annotate a diagram of the retina to show cell types and direction of light movement
• compare rods and cones
• explain the processing of visual stimuli (edge enhancement and contralateral processing)

We’ll then move on to the ear, and you will need to be able to label a diagram and explain how sound is perceived.  Here is a good presentation to help you get through all that!