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madharris

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The parent DNA molecule is unwound one section at a time by helicase exposing the bases on the neucleotide
Free nucleotides (floating in the cytoplasm) attach their bases to the exposed base
DNA polymerase catalyses the nucleotides to join, eventually resulting in 2 identical strands
 

madharris

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What's the difference between a control variable and a control?
I think a control is where you have another experiment where you don't touch to compare it to the other
e.g. in CO2 and water prac, have 2 breakers/cups with water, play in one and compare it to the other

and the control variable is like making it a fair experiment:
e.g. in comparing effect environment on phenotypes making sure that the soil is the same, vulme of water is the same, etc
 

TheOptimist

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What's the difference between a control variable and a control?
A controlled variable is really any external factor aside from the independant and dependant variable that is being controlled, whereas a control in the experiment is usually established to deter any differences from the initial observation.
 

madharris

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can someone quickly outline the role of the nervous system in detecting and responding to environmental changes?
 

Eduard_Khil

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you get this in maintaining a balance, through stimulus (change in temperature), which ultimately is picked up by the receptors (hair cells on skin) which is then transferred by a messenger to the CNS(brain) in which it then uses a messenger to send information to the effector (sweat glands) to produce sweat, and thus as a result through sweat production the body is cooled and hence, maintains the balance :eek:
 

medicore

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Just in case you guys havn't prepared for it yet, you should be aware of how to imporve reliability accuracy and reliability of first hand investigations and evaluatethe accuracy/reliability and validity of second hand information
Does anyone have good notes for this?
 

TheOptimist

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can someone quickly outline the role of the nervous system in detecting and responding to environmental changes?
ok so there is a stimulus (heat/sound/light etc), then receptors pick this up, then this message gets transferred to the CNS the CNS sends a response enacted by effector glands/muscles.
 

madharris

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you get this in maintaining a balance, through stimulus (change in temperature), which ultimately is picked up by the receptors (hair cells on skin) which is then transferred by a messenger to the CNS(brain) in which it then uses a messenger to send information to the effector (sweat glands) to produce sweat, and thus as a result through sweat production the body is cooled and hence, maintains the balance :eek:
That's what I thought, but just needed confirmation. Thanks :)
 

louielouiee

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can someone quickly outline the role of the nervous system in detecting and responding to environmental changes?
Basically it works to regulate & maintain an organisms internal environment in response to their external environment.

Made up of two parts: Central nervous system (CNS) and Peripheral Nervous System (PNS)

CNS:
-This part acts as the control centre for all of the body's responses by coordinating each response.
-Made up of brain and spinal cord
-Receives information, interprets it and initiates a response.

PNS:
- System of nerves branching throughout the body to and from the receptors and effectors.
-This system transmits messages from the CNS and back to the CNS.
-Basically acts as a communication channel for maintaining an internal environment.
 

louielouiee

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can someone quickly outline the role of the nervous system in detecting and responding to environmental changes?
Basically it works to regulate & maintain an organisms internal environment in response to their external environment.

Made up of two parts: Central nervous system (CNS) and Peripheral Nervous System (PNS)

CNS:
-This part acts as the control centre for all of the body's responses by coordinating each response.
-Made up of brain and spinal cord
-Receives information, interprets it and initiates a response.

PNS:
- System of nerves branching throughout the body to and from the receptors and effectors.
-This system transmits messages from the CNS and back to the CNS.
-Basically acts as a communication channel for maintaining an internal environment.
 

madharris

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Does anyone have good notes for this?
- Validity is when, if the method is correct, state improvements for that experiment.
- Reliability - when the experiment is repeated the same results are obtained
- Acurracy - the results of the experiment are compared with reported values to show they are similar
 

medicore

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- Validity is when, if the method is correct, state improvements for that experiment.
- Reliability - when the experiment is repeated the same results are obtained
- Acurracy - the results of the experiment are compared with reported values to show they are similar
By that do you mean like profound scientists and websites?
 

wavess

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Oh I found this:

Accuracy: A measure of how close the data is to the actual true value. Not the difference between accuracy precision. If a man is 1.81m tall, a measurement of 1.743 is precise but not accurate.

Reliability: If a measurement or test is reliable, it gives consistent results each time the activity is repeated. When undertaking an investigating a large number of repeats should ideally be taken, and any readings that vary considerably from the others (anomalous) should be repeated.

Validity: The confidence that researchers put in a set of results and the conclusions drawn from those results. Results are valid if they measure what they are supposed to, and if they are precise, accurate and reliable.
 

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