OCR 2010 A2 Biology Unit 2 - Control, Genome and Environment

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Just because we don't always have an innate behaviour doesn't mean that it's not innate. If someone puts their fingers in your palm, you don't really still have the reflex of clasping your fingers around theirs - but that doesn't mean it wasn't an innate behaviour..........................or does it :colone:

urghhhhhhhh im gonna fail this.

Like if I stick my finger in your mouth, you no longer immediately suck on it. That was an innate behaviour when you were a baby although you don't have it now. Same goes for shivering. Babies don't shiver (muscle wise) until they grow older because they're still pretty undeveloped.

Reply 2281

Sakujo

swirlystar

No shivering is definitely a learnt behaviour, babies can't shiver as a reaction to a cold environment. My teacher always mentions it because it came up one year on an exam paper and the majority of people got it wrong.

Let's put it this way, did you learn to shiver? Is it a reflex that can be changed through experience?

Reply 2282

Just-Some-Guy

swirlystar

Ok I found this online, hopefully it settles things:

"Infants are thought not to be able to do this due to poor development of muscle tissue. Instead, infants use nonshivering thermogenesis (heat production) as a means of generating heat. This is accomplished in infants by burning fat using their storage of brown adipose tissue which is found in infants up to one year of age. During and after this time the muscle structure develops sufficiently to enable shivering to commence."

You were right about babies not being able to shiver, just not the rest.
Sorry to go of topic, i just like to know im right :eek3:

Reply 2283

thekooks

Guinny

Distribution of a species along a transect is just whether or not that species is present.

So to record the distribution of dandelions on a roadside, you would just note down whether there are any in your quadrat.

Abundance is the numbers of individuals of that species along the transect.

Same method as finding the distribution but this time you count the numbers (or estimate using % cover).

thank you

makes much more sense now.

Reply 2284

ViolinGirl

Chunkeymonkey62

Can someone expain the brain (2.4.5) to me? Association areas?

When we did it, we had to learn about the lobes, the hippocampus and other stuff not in the book

Ok-everything you need to know for the brain!

The brain is one of the most important organs in the body. It is involved in the initiation of responses in animals and is also in control of the nervous and endocrine systems.
The largest part of the brain is the cerebrum, this is split into 2 hemispheres which are joined by the corpus callosum. On the outermost layer of the cerebrum, it is highly folded and there are thin layers of nerve cells bodies which make up the area known as the cerebral cortex. The cererbum is in control of 'higher brain functions' such as emotional responses, thought and memory, the abiltity to override certain reflexes and features associated with intelligence.

The cerebral cortex is split into 3 main areas, but there are other areas, such as Brocas area which is associated with control of speech.
We need to know that there are :
1) motor areas -send impulses to motor neurones
2) sensory areas- recive impulses from receptors
3) association areas- compare previous input to judge an appropriate response to a certain situation. Like if you put your hand on an object and it was really hot, you woud think twice before doing this again!

Other regions of the brain are:
Cerebellum- involved in the coordination of movement and posture
Hypothalamus- in control of homeostatic mechanisms
Medulla oblongata- in control of ANS, and has regulatory centres.

Reply 2285

The TSR Star.

Just-Some-Guy

I agree. Babies don't have much development of muscle tissue at all. They can't even lift their own head up let alone shiver :p:

Reply 2286

ViolinGirl

Just-Some-Guy

What ar we debating here? Whether shivering is innate/learned. I would say it is definately innate. It is a reflex and not something we 'think' of to do. Babies are not able to shiver because they haven't developed enough yet to have that reflex. This doesn't mean it is learned. If that was the case then some people would be able to shiver and others woul not be able to shiver, which i don't think is the case!

Reply 2287

Just-Some-Guy

ViolinGirl

What ar we debating here? Whether shivering is innate/learned. I would say it is definitely innate. It is a reflex and not something we 'think' of to do. Babies are not able to shiver because they haven't developed enough yet to have that reflex. This doesn't mean it is learned. If that was the case then some people would be able to shiver and others woul not be able to shiver, which i don't think is the case!

Well put, at least if shivering comes up in the exam we'll all be prepared :smile:

How can gel electrophoresis be described as similar to chromatography?

Reply 2288

swirlystar

Just-Some-Guy

Yeah, that sounds right I was only going by what I'd been told.

The other examples people have given are innate behaviours you are born with and then lose, this you gain so there must be a slightly different mechanism to other innate behaviours. I can't think of another one which you gain :dontknow:

Reply 2289

The TSR Star.

What type of learning is walking?
It is learned but I always thought it was ever so slightly innate. i.e. the stepping reflex in our early months and the fact that even without guidance the vast majority of babies will try to walk regardless. What type of learning is it though? It's all voluntary....

Reply 2290

TX22

how is atp supply maintained in muscle contraction.

is this right:

aerobic respiration occurs in the mitochondria of the muscle cell. The level of ATP regeneration depends on the supply of oxygen and the availability of respiratory substrate.

anaerobic respiration occurs in the sarcoplasms and involves the production of lactic acid which is toxic

also creatine phosphate is transferred into the sarcoplasm of the muscle cell. The phosphate group is transferred to ADP which generates ATP quickly.

Reply 2291

The TSR Star.

creatine phosphotransferase

dont 4get it bruv

swirlystar

I can't think of another one which you gain :dontknow:

You mentioned earlier walking and talking, both are learned behaviours that are somehwat innate and could be argued as having been gained. Human physiology suggests that we are designed to walk, bipedalism is one of our earliest evolutionary adaptaions and is a natural ability that most children develop, and as we are social creatures we have the predispostion to learn language and the vocal ability to express that language through words. However without peers or role models we cannot learn to speak a language, studies on feral children such as Genie have proven this; walking however is more problematic and im not entirely sure, if this came up in an exam i would stick to simpler things:
Innate: Escape Reflexes, Tropisms (Taxes) or Fixed Action Plans
Learned: Speech, tool use, and insight learning

Reply 2294

nbailey8

Is this enough for Golden Rice?

2 genes from Daffodil and one from bacterium Erwina Uredovora inserted into TI plasmids and taken up by bacterium Agrobacterium tumefaciens. This introduces genes into rice embryos. The resulting rice seeds produced have beta carotene in the endosperm which is yellow. Vitamin A produced in our own bodies is from beta carotene.

Reply 2295

Falcon91

The TSR Star.

Walking is learned, no two ways about that. The idea is not most babies try to walk out of the sake of trying to. They try to mimick others, this is the way you learn to talk as well, you hear and listen and try and understand what is being said, its not you TRY out of nothing to do it. Then once youve figured it out, you can do it.
Its like, thing about the way you develop to walk, you start by learning to crawl, then you change your behaviour because all the environment would show that everybody else was walking, then you try it yourself. As posted above, we are developed by evolution to walk, but that doesnt mean all humans will walk nonetheless and so it cannot be considered as innate.

Reply 2296

Falcon91

nbailey8

You might want to point out that the genes inserted produce enzymes which convert precursor molecules of beta-carotene, into beta-carotene and they are placed near the operator sequence for Beta-carotene production and so can activate those genes and beta-carotene can be produced.

Just-Some-Guy

Innate: Escape Reflexes, Tropisms (Taxes) or Fixed Action Plans

Just a heads up, i wouldnt describe Taxis as Tropisms, tropisms only apply to plants growth responses to a directional stimulus.

Reply 2297

mikey_g

Okay, im stuck on this (past paper question)
"Sheep run to empty food container when they hear a tractor engine" - is this operant or classical conditioning?

personally i'd say its classical (running to food container is un/conditioned response, hearing tractor is conditioned stimulus), but the mark scheme says its operant conditioning ('positive reinforcement idea' says the markscheme). helpp!