Courtesy of Dr Anonymous

Explain, with the aid of a fully-labeled diagram, how changes in levels of a condition typically influence the function of organisms.


“Conditions was something that has influenced the functioning of organisms since decades. Long-ago, temperatures were low as compared to now…” [yeah OK, whatever man]




Distinguish between four types of predators classified according to their functional characteristics (i.e. not by the types of prey they eat), and give an example of each.


“Herbivores - those type of predators doesn't kill the prey but it eats it piece by piece (frequently) that might be the same species or different species. e.g. goats eating grass. True predators - predators that kill the prey doesn't affect it pieces by piece but just kills it one time. e.g. lion eating zebras” [eish! mebbe I fail this ONE TIME]


“Parasitoids: Feed of host, which they then kill for only a part of their life cycle” [and then spend the other part reviving it?]



Explain the differences between resource-weighted density, organism-weighted density, and exploitation pressure, and why ecologists find it useful to distinguish between these different expressions of density.


“It is quite useful…Each individual experience different factors due to its fitness, leading to darwins theory of natural selection”

At least they eat light meals...

Q: Compare the dental formulae of humans and rats. What are the implications for the diets of both species?

A: It is evident that rats have no canines or premolars [because] rats do not tear flesh like humans do, because they do not have canines and premolars to assist them in doing so. Rats eat more lighter food as compared to humans.

Do you think they actually know what a rat is...?

Q: Compare the dental formulae of humans and rats. What are the implications for the diets of both species?

A: Only 2 carnivores per jaw on a rat and a diastema gab without teeth and 2 molars per side of a jaw. This suggests that rats have a limited diet (preferably meat) while human have a wide range of diets.

What's worse? Their vicious temperament, or their poor diet?

Q: When comparing the dental formulae of a rat and a human, what features indicate a difference in the diet of the two species? What do these differences suggest about the diets of both species?

A: [The rats have]…one canine on each side and three molars on each side. The rat [therefore] uses canines to rip & tear the food & the molars to grind it. The ripping and tearing is for the meat that the rat eats & the grinding is for the corn it steals from farmers. We have incisors and premolars which are used for biting & chewing, [therefore] we have a diet with softer things such as vegetables etc.

Who knew so much was at stake...

When asked to explain the activation of a protein-digesting enzyme, the student wrote the following. What they were supposed to write was something along the lines of, the enzyme is only activated in the duodenum as the pancreas doens't have any mechanisms in place to prevent self-digestion, and thus it produces the enzymes in an inactive form. This is what they actually wrote...

"…This is to ensure that it does not react with the other substance that it should not react with as prevention of self destruction."

Stating the blatantly obvious...

Q: Explain the activation of chymotrypsinogen [an enzyme].

A: There is a process in which chymotypsinogen is activated...

My job is to secrete cells!

"The stomach has gastric glands which secrete chief and parietal cells."

For the record, the gastric glands are made up of chief and parietal cells. Not that it really matters, as the question was about the activation of an enzyme in the duodenum...

Digestive enzymes in the blood...?!

"Chymotrypsinogen is secreted by the pancreas and enters the duodenum via the blood stream."

Did it never occur to the student that the last thing you want is to have protein-digesting enzymes in your blood?! They would digest all your blood cells, rendering you unable to transport oxygen to your tissues and you would die.

But wait there's more...

Try these on for size:

* "Global climate change has varying theories of prediction". Really? GCC can theorise? And it's clairvoyant; being able to predict and all.

* When carbon is assimilated by plants into complex organic carbon compounds we can refer to this C as being "sunken" and the process is therefore "C sinkage". (Referring to C sinks and sources of course).

* In a question about how animal behaviour, physiology and distribution could be affected by elevated CO2 and the resultant increase in ambient temperatures, one response started: "Insect and plant physiology is affected by CO2 in the following ways..."

* A question required students to outline how biodiversity changes, as a result of global change, will affect the goods and services delivered by ecosystems to humans. This is possibly my favourite faux pas: "Ecosystems provide many cultural goods such as dyes and recreational drugs used in both religious and social ways". Talk about over-share! And pray tell, under what sorting system are dyes and drugs similar?

Could you be more obvious?

In a question requiring an experimental design to test the projection of changed rainfall and it's influence on primary production the students were required to specify the scale and frequency of data collection.

"I would advise performing this sampling in as large an areas as possible with a high number of sites as this sounds like an excellent opportunity for job creation for 3rd year university students which are in desperate need of income in an impoverish society facing economic recession".

Shame! Did they expect marks or sympathy for that comment.

They're out to get us

The following new species were uncovered in a recent exam. They could be deadly - be warned!

* testes fly (keep them protected boys!)
* misquitos (do they have poor aim?)
* mosquitoe (does this one only head for the extremities?)
* This is the scariest: different strains of rainfall (just stay out of the rain like your mom told you too, then it doesn't matter if it's contagious).

Directly indirect?

"The Nitrogen [N] cycle works in conjunction with the CO2 cycle as both play an important role in plant growth and soil enrichment. Thus, by causing deforestation and alike over fishing we directly influence the N cycle".

keh? Wanna make that point a little clearer?

Grammatically speaking

A few excerpts from a recent Functional Ecology exam:

* By enlarge the pattern....

* Did you know that vegetation was an abiotic measurement that should be recorded for observing changes in rainfall under global climate change? Or that rainfall is a biotic factor used to project agricultural output into the future?

* Oh yes, plants have been shown to migrate to higher altitudes to escape rising temperatures. Did you see them pick up their roots and move? Did they do it in the dead of night when there were no witnesses?

* Climate change is causing the increases in CO2 in the atmosphere as well as those increases in temperatures.

Rant: Didn't your high school teachers ever tell you to think before you ink? Good grief!

English isn't your forte is it...?

'...The receptor then makes its what to the enzyme complex it is designed. It is they activated and then releases.'

No wonder the sample sizes were so small…

Estimating population abundance using capture-mark-recapture techniques.

Students Methodology: “Each group attempted to catch as many grasshoppers as possible by direct observation”

Who'd have thought?

Grasshoppers are "Wide ranging megaherbivores"

And the war between tree roots and gravity continues...

Proof that proof-reading really does help!


As the soils increase in depth, the water moisture content increases as there is less to influence the water levels. The vegetation’s roots remain in the upper horizon and this allows there to be a gradient regarding the water levels . The vegetation absorbs water in the upper horizon and the deeper horizons are unaffected by the roots, allowing a higher moisture content.

Oh no! Not another patch of soil!!!

"Within savanna ecosystems, field soils are found at random in patches"

Theoretically possible... I suppose

What do you understand by the term "population limitation"?


Model answer: Population size limited by environmental factors (lack of resources, space...)


Student answer: "Population limitation is restricting the growth of an animal population by de-sexing or... mentally interfering with reproduction"

I'm not looking forward to my resistances kicking in

Question: Why does the population stabilize?

Model answer: resources become limiting at higher pop densities and births will eventually equal deaths.

Students answer: 'When the population gets too large resistance kicks in and the individuals die...'

The most contradictory sentence EVER!!!

"The human population has grown almost exactly geometrically with lots of fluctuations over the years"

I think they covered all the bases... something in there has got to be worth a mark AT LEAST.

Competition for 'high life' decimates human population

Contrary to historical records, the human population did not decline between 1200 and 1300 AD as a result of the plague.

In fact: An increase in the number of factories and resulting competition between humans for the high life decimated the population in the UK between 1200 and 1300.

It seems like 'You have a factory!? I'll KILL YOU!!!' would have been a commonly uttered phrase around this time...

If excel says so, it MUST be true...

The answer:
With density dependent growth models, an experimental population grows till it reaches a carrying capacity of 40 individuals at which time birth and death rates are the same.

What student found:
With density dependent growth models, an experimental population grows till the population size reaches 100000 individuals at which time 70000 die for no particular reason.

At least they are stable...

Students were asked to model population size over time to see at what level population numbers stabilize.

"Our population stabilizes at -0.25 individuals"

So what is that? a quarter of a zombie antelope?

Scary, but true...

An actual conversation that I overheard during a laboratory exercise involving the metabolism of a goldfish between a student (S) and a lecturer (L):


S: Ma'am, we've got a problem...


L: Yes?


S: Well, we're supposed to weigh our goldfish before we start the experiment, right?

L: Yes...

S: Well...we forgot to, so now our experiment is ruined!

L:

S: What should we do?

L: Well, how were you going to weigh the fish before?

S: We were going to weigh a jar of water, put the fish into it, weigh it again and take the difference...

L: So why don't you just do that?

S: What?! You mean we can do that? Even though we were supposed to weigh the fish first?!

L: Well, do you think that the fish is going to lose that much weight during the course of the experiment...?

S: No...

Mosses are small in size and lack vascular tissues. That is why they generally small in size.

Deforestation increases precipitation...?

From an essay on recent floods in China and how these event are related to global climate change...

"Human induced global warming is expected to increase precipitation. This is caused mainly by deforestation that can have a big impact as upland forests can soak up lots of water, but as humans destroy these areas, the water has more land it can run to."


Seriously!? You learn something new everyday.

Oakley, Tree, Rayban, Tree...

Did you know:

In the riverine environment, there are good shades.

I can just imagine a leopard-crawling moss...

... But then I have a rather good imagination.

"When mosses crept on land they had to fight (ferns) for sunlight..."

Sex on the brain...

Did you know:

Ferns have "sexbags" called sori.

Secrete-ing a vote...

This was in an email sent to the entire university... Scary!

So on the 25^th and 26^th of August 2009, take a few minutes of your time to exercise your democratic right to choose your student representatives without fear and in secrete.

mmmm... I just love that tree smell!

Flowers are fragranted of trees to attract birds for seed dispersal

I neva new plants spoke Rasta?

An advantage of a plant developing a seed as opposed to a spore:

"The embryo become protected."

I half wanted to write "Mon" after it...

Excuse me while I cry about global warming...

"A spore is highly sensitive to environmental issues."

Maybe I just can't read...

Either that, or the student's handwriting is really really bad...

Did you know:
Marigold and Plumbago flowers are small in sice.

Apples and Oranges

• Oranges are "citral" fruits
• Bananas are formed by the "herb" floral structure
• Apples are "pomme" fruits
  
  
• Oranges, bananas and apples are all dispersed by Agriculturals.
  

Wow! I knew my heart was racing!

Stimulation of the sinoatrial node causes the heart to beat 70 times every 0.8 seconds!

I always knew I should eat more mushrooms...

Q: What is the biological function of a mushroom?

A: Mushroom has vitamin D so it prevents bone fractures. They break down organic material and recycle nutrients.

Lets hope swine flu doesn't get like this...

"You get antibiotic resistance in drugs and drugs become resistant."

Duck tails! WOOhoo!

When quizzing a student about duckweed selection criteria for population growth experiments:

EEbEE: How did you standardize plant selection?

Student: We chose duckweed with equal sized tails...

(got this answer from TWO students!)

Three cheers for the beginning of a new semester!!!

...Uh... What?

Q: Is the actual size of the leaf the same under a 10x and a 40x lens?

A; Yes, it is supposed to be the same size because the actual size of the object is the same regardless of how she dresses you view it.

...Huh...?

People tem to trust partners with faces similar to their own to marry them.

The definition of a gopher...

Gophers are ecosystems!

How long does a moss take to grow?

The sporophyte of a moss is raised on a stalk-like structure called a seta, which bears a capsule (which makes and releases spores).

A1: The sporophyte consists of a capsule which is usually promptly raised on a seta.
A2: Sporophyte: A stalk-like plant that takes months to grow.

Which is it????

Kung foo fighting fish!

Guppies are fresh war fish!

Isn't water loss a bad thing for a plant???

The leaves may be needle-like to retain water loss. (Emphasis mine).

Not tonight honey, I haven't eaten yet...

Marabou storks starve themselves to avoid having sex.

I thought quads were square things...

Did you know:

Marabou storks sit and quad on the sun.

Mosses and Bleatings

In a moss capsule, there are structures called peristome teeth, which control spore dispersal.

Q: What regulates spore dispersal in a moss capsule?
A: Peristome sheep.

I never knew there was a creature called an "eating"...

Did you know that lemons are dispersed by things called "eatings"...?

I knew it was there when I walked into the room!

Q: Identify the bird on display (it was a Little Stint)

A: a Little Stink

Feel the pine-freshness

Pines have a small surface area which allows for efficient control of gases in the environment.

Why poking your eyes improves vision!

When asked what properties of the eye allow for vision, some genius wrote the following:

'The eyes contain proprioreceptors which help to detect light.'

I don't even want to know what they were thinking...

On the mode of feeding in flamingos:

Flamingos introduce their beak into water, tilted upside down and move their heads from side-to-side. They use erectile tissue while feeding.

At least the majority knew it had something to do with the sea...

A multiple choice question asked the following of a group of 1st year biology students. For the record, cetaceans are the dolphins, killer whales and other whales. Of the 101 students who sat the exam, 64% got the answer wrong...

Which of the following is a cetacean?

Porcupine (17)
Sea horse (28)
Echidna (16)
Mouse (3)
No answer (1)

Powered by grandma!

Q: What evidence are you using to show common ancestry?
A: Fossil fuels.

Smelly ears...?

When asked to explain how the human body maintains balance, one student produced this little gem:

'Olfactory receptors in the ear control balance.'

I, like, totally agree with you, dude...

On a worksheet where students have to descibe the symmetry of a specimen as either 'Radial' or 'Bilateral'.

The symmetry is radical.

Is your pot plant acting strange...?

An annotation on a diagram, referring to a pyrenoid, a cluster of enzymes found in chloroplasts...

"There are dark spots in the chloroplasts. These might be the paranoids..."

Pine trees! A fantastic food source!

Conifers are:

‘…wheat.’

Snibble...?

Q: What teeth of the rat are visible in the provided diagram and how many pairs of these teeth occur in the upper jaw of the rat?

A: upper front teeth: only one pair (2). *He uses it to cut off vegetables and snibble on paper or anything chewable.

And they're, what, 9 years old...?

Todays post is to highlight the terrifying levels of stupidity in the university students that we work with. The answers below were lines taken from selected 3rd grade student's projects on 'Space'. As you read them, compare these to the quality of answers that riddle the rest of this blog. Thanks to Sarah for the brilliant answers!

When asked to do a project on the planets in our solar system I got the following responses from grade three learners:

• Mercury: a heauy silvery white liguid metalic element used in some thermometers and barometers.
  
• Jupiter is the biggest planet and people can't go to Jupiter because it has a sercurity system.
  
• Pluto is close to the sun.
  
• Mercury have many stars.
  
• Pluto was once a planet people ust to come and visit pluto but now they don't becouse it is now a dwarf planet in the whole solar system but now people only visit Neptune, Jupiter, Mars, Mercury, Uranus, Earth, Saturn only becase they are not even dwarf planets ever and ever again.
  
• Mars is a red planet the one that has pancakes in side . . . and when some people go to space they go down and down and down untill they stoped at the grownd . . . and when they go up the see holes in mars and some more pancakes.
  
• Venus is a planet that have aliens.
  
• Earth direct and unembarrassed abour sexual subjects or bodilx functions.
  
• One little boy added photographs of his family and friends after his 3/4 page project on the solar system.

That explains a lot...

Did you know...

'Nerve tissue is divided into CNS and PMS.'

Confusion reigns supreme!

Q: What features place birds in Class Aves and not Class Mammalia?

Birds have specialised pelvic muscles.
Birds have feathers, just like mammals.
They have the ability to singing in a way of calling other organisms (birds).
Birds do not bare an alive bird after reproduction.
Birds do not necessarily consist of fur or hair.
Birds give birth to their young in the form of egg shells.
The feathers of a bird act as the hands.
Since birds do not have mammary glands they can not feed their young ones.
Feathers can be regenerated if they are disturbed or broken.
Birds can fly and walk at the same time.
Birds do not give birth to live animals.
Built for flight not pedal.
They do not show any bipedalism, which is displayed by all other creatures in the class mammalia.
Although birds lay eggs, have parental care and have hair they are placed in the class Aves because they can fly (full answer for 10 marks)
They consist of a beaker used for feeding.
They consist of feathers for flying, as well covering body to prevent body temperature inside body.
Aves have beaks instead of jaws and wings are present, which is not seen in Class Mammalia (except in duck billed platypus)
They are not underwater animals.
Birds do not have tits to feed their young with milk.
The feathers are made of retina.
The class Aves include endothermic, where mammals are ectothermic.

That's gotta be a nasty surprise...!

Q: What is the sex of this rat? Name two structures visible in your specimen that support your answer.

A: Female, ovaries, horned vagina.

At least predators are concerned with their spiritual well-being...

‘…the guppies with increased spot brightness are the ones that are most likely to get prayed upon…’

Darwin would keel over and die...

Q: What is the difference between a homology and an analogy?

A: Homology is the study of humans whereas analogy is the study of animals.

When in doubt...blame the birds!

Q: What evidence from this example can be used to show common ancestory?

A: The hind-limb of a dog, rabbit and frog represent a homology because they all come from birds.

Did ANYONE read their notes...?!

Q: Give an example of a neural tube defect discussed in the lectures. (Correct answer: Spina bifida)
A: Spina bafada
A: Spinal diffidice
A: Spinal bifida
A: Spinodefridia
A: Spinal ambiphida
A: Spinaliphida
A: Spinobifida
A: Spinal befrida
A: Spinal bifrida
A: Spinodiphidor
A: Spinna bofida
A: Spinal diffida
A: Spinabifidae
A: Neural bypiphidal
A: A neural defect could be someone with an extra finger on their hand.
A: Spine abifida
A: Spinol biphader
A: Spinobafidae
A: Syphilicous
A: Spinalfibia
A: Spinal embyphida
A: Spinodefinis
A: Spinaldyfida
A: Spina difidae
A: Spinaldifrida
A: Neuro-dislocation
A: Spinal basophil
A: Spinia bifnia
A: Spinebefilindra
A: Spinal fidalia
A: Cerebral pause
A: Neuropifidimis
A: Spinobefoeda
A: Neurobipiphadal
A: Spiderbitfender
A: An example of a neural tube defect would be spina bifida, where babies are born with an opening at the back with the spines showing.
A: Neural tube bifia

There is no hope...

Q: Describe how the leech has become suited to its lifestyle.

A: The leech can fast feed.
A: Leeches are endoparasites.
A: Leeches can suck up litres and litres of blood and still not get full.
A: Leeches have an anus that also serves as a mouth.
A: Leeches store blood obtained from the previous feed for times of emergency (life or death)
A: Leeches are marine organisms that live in mostly rivers.
A: It injects itself to vertebrates in order to suck out blood for feeding. It’s head is spiny.

...smelly ears...?

Q: What controls balance?

A: Olfactory receptors in the ear control balance.

Ah...it makes so much sense now!

Q: What is their [Flamingos] colour due to?

A: Flamingos are pink for camouflage among other flamingos.

Camouflage against what? The air...? Animals...?

Q: How are some plants adapted to defend themselves against herbivores?

A: Plants can camuflauge with the environment so herbivores do not notice them.

Oh please Mr. Plant! Don't do it! I beg of you...!

Q: How are some plants adapted to defend themselves against herbivores?

A: May have thorns, spikes which harm the animal and may cause it to plead.

The delicate nature of plants...

Did you know that Pelargoniums are "sensative" flowers??

The Croc/elephant shrew/alien monster thingy.

I dug up This little gem from a while back. I think I sent it to Luke or Helen. In any case it is one of my favourite practical dissection drawings. (it's supposed to be a crocodile btw)

Click to Enlarge

I looked around for a nice picture of a croc dissection to make a comparison. Alas, couldn't find one.

Fruit dispersal....

Pineapples use the "agricultural" mechanism of dispersal. Thus, "agricultural" is responsible for spreading pineapple fruits around the countryside.

Scary definitions

This was a piece from a 3rd year essay I marked last month.

Diversity definition: 'Diversity is the state of being diverse'

It wasn't me! I swear! It was the potplant!

Q: How are some plants adapted to defend themselves against herbivores?

A: …and they [plants] can also produce bad smelling substances which will make herbivores uncomfortable around them.