Leaving Certificate Biology 2012

Fergus_

I guess I'll just make this thread to discuss Biology for the LC.

We can also post some questions from the past papers if we're stuck on any too.

I was stuck on this question (2005, Section C, Q13 (b) (iii)

"State two ways in which sperm differs from ova (eggs)"

Aside from sperm being produced in the male reproductive system and eggs being produced in the female productive system, what else could I say for this?

ChemHickey

Fergus_ wrote: »

I guess I'll just make this thread to discuss Biology for the LC.

We can also post some questions from the past papers if we're stuck on any too.

I was stuck on this question (2005, Section C, Q13 (b) (iii)

"State two ways in which sperm differs from ova (eggs)"

Aside from sperm being produced in the male reproductive system and eggs being produced in the female productive system, what else could I say for this?

Sperm have a flagellum and are divided in to 3 parts
Sperm also contain fructose for nourishment and the mitochondria are not found in the head of it...

^^ I think you could say that... not certain, haven't revised it yet :L

BEST THING TO DO IN ANY BIOLOGY QUESTION IS TO DRAW THE DIAGRAMS!!!

ChemHickey

Also talk of the size difference and life span.

leavingcert.

Predictions for the experiments and long questions anyone? is there any topics that could probably be left out?

Fergus_

My teacher thinks that Structure of the Plant will come up (sepals, carpels, anther etc.) and reproduction of a flowering plant.

ChemHickey

Unlikely there'll be a long question on the senses and the endocrine system.

Look over the reproduction and photo/respiration also ecology and genetics too,

Whatsisname

Fergus_ wrote: »

I was stuck on this question (2005, Section C, Q13 (b) (iii)

"State two ways in which sperm differs from ova (eggs)"

One egg is released at a time compared to the millions of sperm released at once.

Eggs are produced usually on the 14th day of the menstrual cycle whereas sperm is continuously produced by males.

partyatmygaff

Sperm contain minimal cytoplasm, a lot of mitochondria, a flagellum and an acrosome containing enzymes used in fertilisation whereas eggs contain a lot of cytoplasm (Due to unequal splitting of cells during egg formation).

There are a lot of other differences but the above would be more than enough for the LC.

ChemHickey

Whatsisname wrote: »

One egg is released at a time compared to the millions of sperm released at once.

Eggs are produced usually on the 14th day of the menstrual cycle whereas sperm is continuously produced by males.

I don't want to sound awful but I wouldn't be sure with this one above...

The question specifically asks about a sperm and an ovum. Not how they're produced or where they are produced.

It probably would be allowed, but, beware of the dreadedbellcurve!! just say too many people got a1's.... they could change the marking scheme to only allow differences regarding them physically..

I could be totally wrong however... and maybe even contradicted my own response (i don't think i contradicted though :L )

FaoiSin

Did this the other night:

• Sperm are smaller
• Have flagellum for locomotion
• Sperm do not usually contribute Mitochondrial DNA to zygote

Edit: Also Sperm - XY Chromosomes Egg - XX Chromosomes

partyatmygaff

Whatsisname wrote: »

Eggs are produced usually on the 14th day of the menstrual cycle whereas sperm is continuously produced by males.

They're not actually produced then. They're released from the Graafian follicle (Due to the LH surge) on the 14th day.

There's a difference between the two phrases and the marking scheme will only accept one and not the other.

Whatsisname

Oops, meant released, my bad!

Manic2

My teacher thinks it's gonna be a bitch of a paper this year!

She thinks we'll get our genetics and ecology LQ's.

She thinks one of Q14/15 will be two parts plants due to many people being able to get by previously on learning everything but plants (However, not having a choice in the process)

David1994

Manic2 wrote: »

My teacher thinks it's gonna be a bitch of a paper this year!

She thinks we'll get our genetics and ecology LQ's.

She thinks one of Q14/15 will be two parts plants due to many people being able to get by previously on learning everything but plants (However, not having a choice in the process)

Oh how fun :P What you learning for the plants?

leavingcert.

does anyone have a link to notes or able to send me their notes on plant reproduction, like mainly the formation of the pollen grain and the other thing(yes, thats how bad i am at that chapter)... i can't understand it at all and my book seems to have a lot of waffle in it!

FaoiSin

leavingcert. wrote: »

does anyone have a link to notes or able to send me their notes on plant reproduction, like mainly the formation of the pollen grain and the other thing(yes, thats how bad i am at that chapter)... i can't understand it at all and my book seems to have a lot of waffle in it!

I used the Revise Wise for that part. Explains it excellently step by step with diagrams

siobhan93

Fergus_ wrote: »

I guess I'll just make this thread to discuss Biology for the LC.

We can also post some questions from the past papers if we're stuck on any too.

I was stuck on this question (2005, Section C, Q13 (b) (iii)

"State two ways in which sperm differs from ova (eggs)"

Aside from sperm being produced in the male reproductive system and eggs being produced in the female productive system, what else could I say for this?

You could say they're non-motile, they more numerous etc.

Cruel Sun

Biology is'nt my best subject, could anyone help me with this one.

"Water is essential for photosynthesis. Briefly outline how water from the soil reaches the leaf."

Would you just go on about osmosis?

Cheers

reznov

Water from the soil reaches the leaf through the adhesion/cohesion model proposed by Dixon and Jolly. Water enters the plant through root hairs (by process of osmosis), but what actually pulls it up is transpiration tension created in the xylem vessels. The transpiring water vapour leaves a water debt in cells, which essentially pulls water up through the roots and stems, to the leaves, to replenish cells with water.

(basically speaking, may not be 100% accurate)

siobhan93

Martin_94 wrote: »

Biology is'nt my best subject, could anyone help me with this one.

"Water is essential for photosynthesis. Briefly outline how water from the soil reaches the leaf."

Would you just go on about osmosis?

Cheers

water is lost in the leaf by transpiration, water it then enters the roots by osmosis. There's also root pressure but this doesn't cause water to go all the way up the leaves but you could mention it and then you would have to go on about the cohesion/adhesion model. The water molecules pull each one up after eachother (cohesion- when similiar molecules stick together), this then creates tension in the xylem vessels, this tension causes the xylem vessels to become narrow during transpiration but they return to their normal shape after transpiration!

ChemHickey

Martin_94 wrote: »

Biology is'nt my best subject, could anyone help me with this one.

"Water is essential for photosynthesis. Briefly outline how water from the soil reaches the leaf."

Would you just go on about osmosis?

Cheers

Draw a diagram showing water entering with arrows, forces between water. root pressure, transpiration and water being pulled up by hydrogen bonds etc. then from that you can see what you need to explain.

Bubbleope

i have my notes up online if anyone wants to have a look??
just pm me if you want the link cause i feel like a weirdo putting the link here. xD
the link is to everything we need to know on unit one.
i'll put up the other units this week. (:

SarahMc0

biologywithjoe.com has really good notes. I'm only working off the questions & answers and the actual notes now, and they really cover everything!

Mayo_Boy

SarahMc0 wrote: »

biologywithjoe.com has really good notes. I'm only working off the questions & answers and the actual notes now, and they really cover everything!

Looks like an excellent site but why aren't the questions & answers up for units 1 and 2 ?

SarahMc0

Mayo_Boy wrote: »

Looks like an excellent site but why aren't the questions & answers up for units 1 and 2 ?

I don't know tbh, I got the notes a while back, and they were there then? Maybe it's just a glitch- you could try again in a day or two?

PTheArtist

Anybody have any good notes/links on how to dissect and identify the different parts of the heart?

UnholyGregor

i was going to study biology.. then i looked at the exam papers and lol'ed when i seen it actually had true/false q's in section one...... if i dont get an a1 in that i might actually implode with shame....

Namlub

You're no reznov

Bubbleope

i've everything unit 2-wise done and up online now! (:
unit 3 will be up soon. (:
pm me if ye want the link!!

leavingcert.

UnholyGregor wrote: »

i was going to study biology.. then i looked at the exam papers and lol'ed when i seen it actually had true/false q's in section one...... if i dont get an a1 in that i might actually implode with shame....

go away. it's not that easy so stop showing off! its far from easier and there are much easier subjects to get an A1 in...you see one true and false question in the short questions and u think the paper is easy?

Stalin and rugby

leavingcert. wrote: »

go away. it's not that easy so stop showing off! its far from easier and there are much easier subjects to get an A1 in...you see one true and false question in the short questions and u think the paper is easy?

Biology is the easiest subject out of all the maths and sciences..