Sunday 4 September 2016

Camouflage

Practice Question
A recent New Zealand study compared the size, shape and pigmentation of hundreds of leaves of Pseudowintera axillaris (horopito, also known as the New Zealand pepper tree) and small Alseuosmia macrophylla (toropapa) plants, and found a match. Over a third of the leaves of the two species cannot be statistically distinguished from one another.  Toropapa were possibly eaten by moa before the arrival of humans quickly decimated the moa population.  Unless the plants are flowering or fruiting, the only fast way to tell them apart is to taste a leaf.  Horopito leaves a pungent, hot peppery taste and a numb tongue when the leaf is chewed, while toropapa is highly palatable.
Small toropapa (left) and horopito seedling (right)

Name and describe the relationship between Pseudowintera axillaris and Alseuosmia macrophylla. Discuss the adaptive advantages and disadvantages of the relationship to the two species of New Zealand flora, including any survival strategies they employ.
Things to include in my answer:
  • Name the relationship
  • Adaptive advantages/disadvantages of relationship 
The relationship could be commensalism, but commensalism is when one benefits and the other is unaffected, but because of mimicry is affected because it could probably get eaten.  The harmless plant looks like the poisonous one.  The harmless plant could get eaten and because the harmless plant looks similar to the poisonous one,  they might think the poisonous plant is also harmless.  Advantages of this is that the harmless plant is less likely to get eaten.  Disadvantages of this is that the poisonous plant is more likely to get eaten.  








Wednesday 24 August 2016

Migration


Migration is a regular, repeated return journey, usually over long distances.  Usually annually of just once in a lifetime. Homing is a return journey to a home base after searching for food or mates. Migration and homing are very similar in the way that it is a journey. However, they are also different because migration is moving from one place to another and then returning to the first place.  Homing is when you’re returning home from something like a scouting trip/scavenging trip.

It is usually birds or fish migrating somewhere, or homing, and when they do this they use navigation to find their way. There are different ways of navigation that these animals use. One of way of navigation is star navigation. Using the stars, birds are able to find their ways home/find their destination. They do this through recognizing groups of stars or constellations, which are indicators that they are going the right way, and fly in that direction. Another way of navigation used are visual cues. For example, motorways are visual cues used by birds to navigate. Other visual cues could be trees. The disadvantage with this, however, is that with things like deforestation taking away trees, birds will be disadvantaged when migrating because a visual cue they once used for navigation is no longer there.

The Bar-tailed godwit is a bird who migrates from NZ to places like China, or from Alaska to China. These birds are known for taking the longest non-stop migration flights. This is due to the fact that they when migrating, the pass over the ocean which has no resting places to offer the birds, and so they have no choice but to fly until they reach their destination.

Biorhythm

A rabbit is active at dawn and dusk.  Its normal activity is recorded in a lab for 6 days, then recorded in constant darkness for another 10 days.  There is still a pattern to the rabbits behaviour but it starts 20 mins later each day.  

Zeitgeber, entrained, biological clock, endogenous, exogenous, circadian, circa tidal, phase shift, period of, nocturnal, diurnal, crepuscular, biorhythm, free running.  

In class today we had to rewrite the paragraph above but had to rewrite it using the list of words (also above).  Here is my finished result:

A rabbit is a crepuscular animal, meaning it is active at dawn to dusk.  This also means that the rabbit is neither nocturnal (active during the night) or diurnal (active during the day).  The rabbits biorhythm is circadian, not circa tidal, which means that the activity happens daily during a period of 24 hours.  The biorhythm of the rabbit cannot be circa tidal as the rabbit does not live near the sea/tides.  Because the rabbit is still active even after the zeitgeber has been taken away this means that the rabbit's rhythm is endogenous, not exogenous.  The rabbit is being entrained as the biological clock is being reset (before the zeitgeber is taken away).  The rabbit's rhythm becomes free running as the rabbit is still active in a regular pattern even after the external cue is removed.  The phase shift of the rabbit starts to occur 20 mins later after the zeitgeber was taken away.

Wednesday 27 July 2016

Euthanasia

Euthanasia is a very debatable topic, as my Year 13 Bio class found after we had a debate about it.  Our class was split up into two groups - one for the legalization of Euthanasia, and the other was against it.  My group was the group that was for the legalization of the Euthanasia and this is our debate plan:  https://docs.google.com/document/d/1bvr2m4gfYh3-a1TZ7qkLBxhoGYaueEpW4fKVjMFldxY/edit.  On this doc you will find our main points as to why we think it should be legalized, and what we thought the other group would rebut with.

Tuesday 5 April 2016

Auxin

I wasn't here when we were learning about auxin due to some unforeseen circumstance, but, from what I can see from my peers' work they have done on auxin, I can gather that auxin is a hormone that plants have, which causes plant cells to elongate in their shoots.  Auxin is involved in the regulation of plant growth.

In this presentation that Rita has done, it shows auxin in action.  Basically what is happening is that whilst the sun moves along in the sky and at the same time, auxin is being produced in the tip of the plant.  The side where the sun is not shining, is the side of the plant where the auxin travels.  Photo-tropism then occurs.  The cells in the side of the plant that the auxin is diffusing then starts to elongate.  Now, because the cells on the shadier part of the plant are longer than compared to the cells on the sunnier side (of the plant), the stem is then forced to lean over to where the sun is shining.




Credit to Rita for the presentation.

Monday 14 March 2016

My Critter

This is a flurtle.  It burrows underground when disturbed.  What is the adaptive advantage of this?

Wednesday 9 March 2016

Assessment Reflection

We have recently just finished our first assessment, and I think I did okay.  The assessment was on the topic of homeostasis, and how homeostasis helps to regulate the blood glucose levels within our body.

I think this assessment was pretty difficult.  There was a lot of researching to be done, and then that research had to be put into our own words - something that is hard to do, especially when the words are big and science-y.  The hardest part was probably trying not to plagiarize, and to put the big, science-y words into my own words.  The easiest part was doing the research.

Compared to Year 12, I would say that Year 13 Bio is a tad bit easier.  I think this is because we already have prior knowledge from last year, and that's helpful because many of the assessments and stuff that we're learning about, we already learnt last year.

Some tips for next years Year 13 Bio class are, listen to Miss Wells.  Also, DO NOT PROCRASTINATE.  Procrastination will almost always lead to failure.