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Multiple Choice (1 Viewer)

sslions

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mithril1337 said:
Q 9) Current reproductive techniques can be used to alter the genetic composition of a population. Some of these methods were also used in the nineteenth century by Gregor Mendel.
How did Mendel use reproductive techniques in his experiments?

(A) he artificially inseminated the pea plants to achieve wrinkled seeds
(B) he cloned the pea plants with round seeds to increase their food supply
(C) he created a transgenic species by mixing tall pea plants and short pea plants
(D) he artificialy pollinated the pea plants to test for different genotypes in the offspring (credit to hoca pontis)

D states 'he artificialy pollinated the pea plants to test for different genotypes in the offspring' Mendel wasn't testing for 'genotypes.'

there for A is the correct answer since the statement is true.


Lols please disprove me this is what a friend said.....

Lol, you can't artificially inseminate a plant! Mendel tested for different 'factors' in offspring, and these factors are our genotypes so answer is D.
 

joshuaali

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Stipe Pletikosa said:
What are you talking about.

The reactiong that took place was AB splitting to become two sepearte products of A and B

The enzyme was labeled and the Substrate was AB

The reaction took place and produced the products AB you half wit.

Therefore when the question asks 'What is the substrate' the answer is AB = C
For question 1:

a) C cannot be the substrate since it is not changed in any way. In fact, C is the enzyme - the catalyst.
b) (b) shows the enzyme-substrate complex. It is what is formed when the substrate bonds onto the enzyme's active site.
c) This shows the final product: A and B joined together to form "AB". A substrate, however, is the reactant(s), not the product(s). If you are not familiar with those terms, the substrate (reactant) is what's present at the beginning of the reaction, not after.
d) A and B (separated) is what's there initially, but not finally.

Analogy: You bake a cake. Somebody asks you "What are the ingredients?" You do not reply with "a cake"; you say "Flour, eggs, sugar, etc.".
 

joshuaali

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Stipe Pletikosa said:
Question 1 is officialy C

As extracted from a key source:
'The Products are the substances that the Substrate(s) become. One substrate can be split, or two substrates can be joined'

In this case it was 2 substrates joining. You cant just ignore the arrows in the diagram! They showed the flow of the reaction.
And yes, you are contradicting yourself:

'The Products are the substances that the Substrate(s) become. One substrate can be split, or two substrates can be joined'
The products are the substances the substrates becomes, therefore the substrate(s) is/are the reactant(s). A substrate can be split or multiple substrates can be joined together (the latter was the case in this scenario).

In this case it was 2 substrates joining. You cant just ignore the arrows in the diagram! They showed the flow of the reaction.
Indeed you are correct. And when you take into consideration what you said above, it is obvious that the answer is D.
 

fartx2

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joshuaali said:
For question 1:

a) C cannot be the substrate since it is not changed in any way. In fact, C is the enzyme - the catalyst.
b) (b) shows the enzyme-substrate complex. It is what is formed when the substrate bonds onto the enzyme's active site.
c) This shows the final product: A and B joined together to form "AB". A substrate, however, is the reactant(s), not the product(s). If you are not familiar with those terms, the substrate (reactant) is what's present at the beginning of the reaction, not after.
d) A and B (separated) is what's there initially, but not finally.

Analogy: You bake a cake. Somebody asks you "What are the ingredients?" You do not reply with "a cake"; you say "Flour, eggs, sugar, etc.".
im pretty sure hes right. its a simple chemical reaction, where products are made. i saw this example in class, its the glucose +glucose= maltose one.

btw
hi josh, its me, your halo buddy
 

willhowden

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Stipe Pletikosa said:
What are you talking about.

The reactiong that took place was AB splitting to become two sepearte products of A and B

The enzyme was labeled and the Substrate was AB

The reaction took place and produced the products AB you half wit.

Therefore when the question asks 'What is the substrate' the answer is AB = C
No!
The subrate>S< were A and B (answer D). The reaction that took place was the joining of substrates A and B. The PRODUCT was answer C, as the flow diagram clearly represents. How can't everyone see this!

A - Product 1
B - Product 2
C - Enzyme
AB - Substrate

THE ANSWER IS D!!!
 

JACKSON5110

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joshuaali said:
1. D - I believe the substrate is the reactant, not the product.
2. B
3. A - The rings are characteristic of xylem vessels, and xylem transports water and mineral ions.
4. C - Prevention is better than cure.
5. B - The treatment is the independant variable. The number of visible bacterial colonies depends on that variable, and is thus the dependant variable.
6. B
7. D
8. D
9. D
10.A
11.B
12.A
13.C
14.A (I'm not sure about this one; my friend says C)
15.D
but doesnt the letter c (answer A) represent the substrate as shown in this diagram....
 

sslions

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Stipe Pletikosa said:
What are you talking about.

The reactiong that took place was AB splitting to become two sepearte products of A and B

The enzyme was labeled and the Substrate was AB

The reaction took place and produced the products AB you half wit.

Therefore when the question asks 'What is the substrate' the answer is AB = C
Mate, look at the diagram properly. AB wasn't split; AB was formed. A is a single substrate and B is a single substrate and when reacted together in the presence of C (enzyme), they produce AB. lol, you just contradicted yourself yet again; you stated "the substrate was AB" and again stated "reaction took place and produced the products AB". Damn man!
 
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joshuaali

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JACKSON5110 said:
but doesnt the letter c (answer A) represent the substrate as shown in this diagram....
In that reaction, yes, however, as mentioned by Stipe Pletikosa, "One substrate can be split, or two substrates can be joined". In your example, it was the former. In today's exam, it was the latter.

Example: In DNA replication (hey, this was another question in today's exam), an enzyme named DNA polymerase assists in the polymerisation of new DNA strands. What that means is it takes single monomer units and bonds them together to form a large polymer (i.e. a DNA strand, in this case). Ligase is another enzyme involved in DNA replication that works by bonding two smaller units into a larger one.


fartx2: Which Halo buddy? o:
 
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eppingMCE

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1. A (wasn't sure)
2. B
3. D
4. C (A is not a preventative measure, its only what the scientist did)
5. B (D is independant, dependant is what ur testing which depends on the variables)
6. B
7. D
8. D
9. D
10. A
11. B (took me ages to figure it out with so many punets squares all over my page)
12. A
13. C
14. C (they both help in conserving water, adosterone is secreted by the adrenal gland and causes the kidney to reabosorb more salt, thus the water follows, ADH is secreted by the hyperthalamus and makes they kidney more permible thus more water is reabsorbed)
15. D
 

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mithril1337 said:
Q 9) Current reproductive techniques can be used to alter the genetic composition of a population. Some of these methods were also used in the nineteenth century by Gregor Mendel.
How did Mendel use reproductive techniques in his experiments?

(A) he artificially inseminated the pea plants to achieve wrinkled seeds
(B) he cloned the pea plants with round seeds to increase their food supply
(C) he created a transgenic species by mixing tall pea plants and short pea plants
(D) he artificialy pollinated the pea plants to test for different genotypes in the offspring (credit to hoca pontis)

D states 'he artificialy pollinated the pea plants to test for different genotypes in the offspring' Mendel wasn't testing for 'genotypes.'

there for A is the correct answer since the statement is true.

Lols please disprove me this is what a friend said.....

He wasn't artificially inseminating in an attempt to achieve wrinkled seeds. He wasn't artificially inseminating at all... The definition of AI is when sperm is placed into the uterus or cervix using artificial means. It's not possible in plants.
 

mithril1337

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shona1990 said:
He wasn't artificially inseminating in an attempt to achieve wrinkled seeds. He wasn't artificially inseminating at all... The definition of AI is when sperm is placed into the uterus or cervix using artificial means. It's not possible in plants.
Thx shona

that makes me feel much better , i chose (d)

can't wait to tell 'im off cheers :)
 
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bmwz4

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guys what is the final answer for question 4 i put D?
 

Punksta07

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Its funny to see the amount of critism that guy faced about his contradiction, the answer is still D though and he did contradict himself. Also AI is different to self pollination and self pollination only applies to plants...overall the MC was easy...only had trouble with the percentage question....25% am i right....assuming both the parents were Hetrozygous u get 3 normal and 1 infected, therefore 25%....it was tricky, i thought it was going to be 100% (chances are still chances) but the key word "probability" made it obvious
 

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bmwz4 said:
guys what is the final answer for question 4 i put D?
It can't be D. I therefore put C - why it can't be D is that it doesn't state anywhere in the scenario that the Wollemi Pine still exists and does actually come from outside the country therefore "Preventing the importation of Wollemi Pines into Australia' can't be correct. They stated "The last small population of Wollemi Pines grows in a remote part of a national park in Australia"
I also believe Wollemi Pine is native to Australia?

But they specifically pointed out the fact Phythophthera lives in the soil therefore washing soil from scientist's shoes will prevent further spread of the fungus to other monocots and thus these pines. (Which i've read somewhere in a text book to do with Phythopthera - If I can find the source i'll put it up.)

It was a trick question anyway, since the first thing you usually suspect when you 'prevent the spread' of something is to stop it from coming into the country, quarantine, protecting our wildlife and agriculture etc. Personally I think even if there were Wollemi Pine being imported in, it wouldn't exactly help these scientists who are looking for "strategies to prevent these pines becoming infected"


For question 1:
I did put C, but now looking at the question in the booklet closer again, it's more likely it's going to be D:

My argument? The fact the diagram states they want a "Lock and Key" Method. In the various textbooks i've looked at, the lock and key method shows that answer C) to that question is the product, whereas A B or answer D) is the substrate. These are actually "theories of enzyme action"

I still believe i'm right with the answer C in some cases to do with the lock and key method, BUT in this SPECIFIC diagram, it shows the substrate being 'locked' and the product being created, I believe the answer is D. And, I don't think anyone who has argued is correct or incorrect about C also being a substrate, but not according to this diagram, and the fact they want you to use the theory to determine it.
 
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mzduxx2006

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phoebe2007 said:
also i'm pretty sure with 14 it's A... i origionally had C until i changed it.. and there are lots of different answers here.. BUT i think a because if he had a low blood pressure then both would be released and aldosterone is only to either raise the blood pressure or rasie the salt ions in the body.. and the question is not asking for any of that it is simply saying the marathon runner is dehydrated- meaning the cells do not have enough water, the water balance is out. This would mean there is already too much salt.. so no more salt is needed.
thats my take...
well the question said he was dehydrated.


basically

adh= water retention

aldosterone= salt retention\

therefore adh would have to be released and aldosterone would be decreased in order to rehydrate the marathon runner. that was my answer. i dont have the sheet with me but i think it was a.
 

mzduxx2006

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shona1990 said:
He wasn't artificially inseminating in an attempt to achieve wrinkled seeds. He wasn't artificially inseminating at all... The definition of AI is when sperm is placed into the uterus or cervix using artificial means. It's not possible in plants.
yea it was d im pretty sure because he did artificially pollinate by isolating both stamens of the plants. it was either c or d. i chose d.
 

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mzduxx2006 said:
well the question said he was dehydrated.


basically

adh= water retention

aldosterone= salt retention\

therefore adh would have to be released and aldosterone would be decreased in order to rehydrate the marathon runner. that was my answer. i dont have the sheet with me but i think it was a.
Nah, the answer was ADH and Aldosterone.
The reason:
-ADH DIRECTLY is involved in water reabsorption (as it changes the permeability of the collecting duct)
- Although aldosterone is not directly involved in water reabsorption (it is directly involved in salt reabsorption), as salt is reabsorbed water moves as well via osmosis.
 

readert

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mzduxx2006 said:
well the question said he was dehydrated.


basically

adh= water retention

aldosterone= salt retention\

therefore adh would have to be released and aldosterone would be decreased in order to rehydrate the marathon runner. that was my answer. i dont have the sheet with me but i think it was a.
Nah, the answer was ADH and Aldosterone.
The reason:
-ADH DIRECTLY is involved in water reabsorption (as it changes the permeability of the collecting duct)
- Although aldosterone is not directly involved in water reabsorption (it is directly involved in salt reabsorption), as salt is reabsorbed water moves as well via osmosis.
Also, the other reason why aldosterone would be secreted is because the runner would lose salt through sweat production, and thus would need to replace salt levels for a healthy blood pressure.
 

kobina

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readert said:
Nah, the answer was ADH and Aldosterone.
The reason:
-ADH DIRECTLY is involved in water reabsorption (as it changes the permeability of the collecting duct)
- Although aldosterone is not directly involved in water reabsorption (it is directly involved in salt reabsorption), as salt is reabsorbed water moves as well via osmosis.
Also, the other reason why aldosterone would be secreted is because the runner would lose salt through sweat production, and thus would need to replace salt levels for a healthy blood pressure.
ijus coz there is salt absorption doesnt have ne effect of the amount of water in an organism. if theres salt absorption all there will b is more water in blood stream, rather than cells. SALT=BLOOD PRESSURE in biology
 

fuzzyfaction89

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I got the following:

1) C ('D' seems to be the correct answer. If you ask me, the question sort of contradicts the meaning of an enzyme - a biological catalyst that BREAKS DOWN molecules to help speed up reactions. If the arrows were facing the other way, it would have made much more sense/logic, and then C would have definetly been the answer).
2) D
3) D (i'm wrong - it's A apparently - don't know how you're meant to tell... I was never taught xylem tubes were thicker in a plant!)
4) A (i'm wrong, it's C - prevention, etc)
5) B
6) B
7) D
8) D
9) D
10) A
11) B
12) A
13) C (it's not D because of the word 'adapted')
14) C (This seems to be causing speculation. when adh is released, salts enter the bloodstream, but as a result, water passively follows - hence my reasoning for an increase in both adh and aldosterone)
15) D
 
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