Species A and Species B- WAXY CUTICLES AND SALT CRYSTALS (1 Viewer)

[shobadaynature]

mean water level...

Psshaw, I think I got them the wrong way around! Great. What was the whole mean water level thing about?

I had to stop and really think about this, but it's probably saying that when the tide is highest, then the water submerges up to the high water mark, so part of the inland plant is partially submerged - then i put the salt crystals for that one

the lowest mean water level is mean the water level is low, or at low tide, it only comes up to the plant nearer to the sea, therefore the other plant needs some other ways to keep salts from entering it. - i put the waxy cuticles for this one...

oh well...i duno if i got it right, seems kinda ambigious...:S

 

[kyu_chan]

Yeah basically Species A which had salt crystals on it's leaves is an adaptation. They have special features in their leaves which accumulates salt and discards them on top of their leaves, ready for rain to wash them off. Species B has thick waxy cuticle which is an adaptation to conserve water, tthis is needed by plants living on land. So yeah thats correct as uve said.

Yup ^^ Tht's exactly what I did ^_^

 

[veterandoggy]

It was confusing, took me llike ten minutes to figure out this one. the salt secreting plant would be closer to the sea, the waxy cuticle would be further inland.

jeez, was it that difficult? i'm not getting a high band 6 mark, but i had reached that question in the reading time, and hadnt even looked twice at it, cos it was obvious that species b would need to get rid of more salt than species a. i didnt go into detail about the enantiostasis though. darn......

before anyone tries faming me let me tell you that i am the student that actually listens in class, and i get approx. 70% of the work first time, hence my total study for bio not exceeding a day of hardcore study(Give me a break!! i had 3u maths the day before, and i think i know which one needs more time).

 

[frootloop]

I reckon that both are correct...

you'll get the marks as long as you could 'justify' your answer sufficiently... so using either the water mark means or the proximity to the sea.

Just a theory

*Hopes that this is the case*

 

[Digital_Spork]

lol, that question was pretty straight forward...

 

[Zali]

yeah i said salty leaves was closer to water but i dont see why waxy needed to conserve water the high tide mark still reached his area. i said waxy was for salt exclusion where as exclusion wasnt sufficient for salty as it was constantly in contact with salt water so he needed to excrete salt.

 

[stu_jacks88]

jeez, was it that difficult? i'm not getting a high band 6 mark, but i had reached that question in the reading time, and hadnt even looked twice at it, cos it was obvious that species b would need to get rid of more salt than species a.

No once i look at it now, no it wasnt that confusing, i just confused myself while looking at it. At first i thought along the lines that because the environment around the tree has more salt than the organism then the tree would need to conserve water, thus the waxy cuticle (the same way that a salt water fish loses salt to its environment). But when i tried to explain the salt excretion of plants in land i found that it was the other way around. And then i kept confusing myself and whiting out everything for a period of 5 - 10 minutes.

 

[MiniT]

Ok I think I completely misread the question. My interpretation was that both species were in similar environments. So Species A had the highest water mean because it had adaptations to expel salt from it's leaves thus retaining water. Whereas Species B had waxy cuticles which were effective in preventing water loss by transpiration but were useless in protecting the plant from the salt levels.

Oh well I hope I get some marks cos I did justify my answer...

 

[MiniT]

yeah I'm glad I got it correct. Since you have nailed the exam can you tell me about the colour blindness thingy?.

Will Jack be colour blind?

From the information given, the mother could have 2 possible genotypes. She could either be a carrier or she could be homozygous normal. The father is normal since there is no history of colour blindness in his family. So when you draw up a punnet square for the 2 genotypes you find that Jack has 3/4 chance of being normal and a 1/4 chance of being colour blind.

 

[daemon22]

Species A- closer the sea because I think salt crystals are important for salt regulation and sea contains a lot of salts LOL I 'm not sure...

species B- inland because waxy cuticles are used to reduce water loss and water loss is a problem for organisms live on land

hmm, I said A was near the sea, because its environment was salty and hence it had to exclude salt from its leaves (enantiostasis), thus its leaves would have salt crystals on them; and B was on the land due to water conservation thus waxy cuticles to prevent water lost by evaporation

 

[fat_loser]

That species A and B question wasn't too hard to get once i got my bearings... I mentioned enantiostasis and adaptations type stuff so i was pretty confident with my answer - eventhough 90% of my answer was bull dust, but that goes without saying- until my teacher who was waiting outside the exam room told me that Species with the salt leaves was terrestrial and species with waxy leaves was marine. I had a pretty full on, all out argument with him in the middle of the hallway so im hoping that i'm right and he's wrong...

 

[daemon22]

That species A and B question wasn't too hard to get once i got my bearings... I mentioned enantiostasis and adaptations type stuff so i was pretty confident with my answer - eventhough 90% of my answer was bull dust, but that goes without saying- until my teacher who was waiting outside the exam room told me that Species with the salt leaves was terrestrial and species with waxy leaves was marine. I had a pretty full on, all out argument with him in the middle of the hallway so im hoping that i'm right and he's wrong...

wtf :| your teacher's gotta be wrong, atleast - better be~!

 

[Metroid Hunter]

I found the diagram confusing for this question but once you figure out what it means, its not difficult. It took me a minute to find the LAND label on the bottom of the graph and then i figured out what it meant. I had the plant that excretes salt closer to the sea than the other plant, but I justified it by saying that the plant with the waxy cuticle cannot get rid of excess salt so it has to remain inland while the other plant can. And then i blabbed on about diffusion and excessive uptake of salts because of concentration gradients. So i missed the bit about water conservation, but I think my answer is ok.

 

[intrik8]

At first, I when I looked at the question, I was like.. WHAT THE SHIT IS THIS? I decided to leave that question last because it required me to think a little - something I'm not good at doing. However, after staring at the question for around 10 minutes, the light bulb up on the ceiling above me, flickered and turned brighter... It was pretty easy after figuring out which line is what, and all the rest had to be done adding in the purpose of having those sorts of structures and adaptations in considering their location...

 

[_blank]

The question really threw me off because I couldn't understand why the water would be HIGHER nearer to land and LOWER towards the sea....but at the end I just ignored that and wrote A is near the sea (dotted line) and B is near land (solid line).

I didn't mention enantiostatis...only that the salt crystals are evidence of salt secretions, which is an adaption of plants to saline environments. Hope that gets me the mark anyway...

 

[mynameisgone]

btw everyone, high meant the high tide mark, the furthest in the water can reach, and low is where the tide is lowest. therefore the right of the diagram is always underwater, and the left never

 

[frootloop]

btw everyone, high meant the high tide mark, the furthest in the water can reach, and low is where the tide is lowest. therefore the right of the diagram is always underwater, and the left never

Hey hey! V good logic. You're a thinking one! It didn't even fully occur to me that the info meant that. Now I'm almost fully confident of my answer: the one closer to land had waxy cuticles and the one closer to the sea had leaves with salt crystals. The question is much simpler than I thought.

 

[veterandoggy]

From the information given, the mother could have 2 possible genotypes. She could either be a carrier or she could be homozygous normal. The father is normal since there is no history of colour blindness in his family. So when you draw up a punnet square for the 2 genotypes you find that Jack has 3/4 chance of being normal and a 1/4 chance of being colour blind.

umm, may i point out that colour blindness is sex-linked (like, the Y chromosome doesnt have a characteristic, dude). and if you think for a few seconds, you would have realised that maria or whatever her name was has a normal X from her mother and a normal X from her father. it also said that the colour blindness was in her family, not her husband, so the child will NOT contract the colour blindness of his old generation. well, i guess you could say goodbye to a few marks.

 

[snickerdoodle]

umm, may i point out that colour blindness is sex-linked (like, the Y chromosome doesnt have a characteristic, dude). and if you think for a few seconds, you would have realised that maria or whatever her name was has a normal X from her mother and a normal X from her father. it also said that the colour blindness was in her family, not her husband, so the child will NOT contract the colour blindness of his old generation. well, i guess you could say goodbye to a few marks.

Why does Maria automatically have a normal X from her mother? Her mother is a carrier (2 of her brothers had the disease and her husband didn't), so Maria could conceivably be a carrier also. If you drew up a Punnet square for her parents it was XbY times XBXb - homozygous normal or heterozygous carrier.

If you drew up a Punnet square, you would've had XBXb times XbY, and since we know Jack is a boy, he's either XBY or XbY = 50% chance of colour blindness.

It was a vague question, because we have no way of actually knowing if Maria is a carrier. But it since the whole point is sex linked diseases you'd assume she is.

 

[danieljarvis]

why do you say maria got a normal gene from her mother buddy. she had a 1/2 chance of getting the affected gene from her mother because her mother was a carrier. She got one X from her father that was normal. and then her mother was a carrier so she had a 1/2 chance of which X gene she would get. so she could have been a carrier dickhead. then if she was a carrier her son had a 1/2 chance.

say hello to some more marks you idiot. i know that answer, i went through it with my teacher after. we got the same as everybody hear who is in the know.

And to the person you quoted, you were wrong, but closer than this guy. It doesnt matter what the father is because he passes his Y chromosome to Jack which isnt involved in Sex-Linked traits.