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Edexcel A2 Biology SNAB 6BI04 ~ 6BIO5 June 2016

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Reply 1000

aksdj

is anyone revising as content?

Reply 1001

Ikran

Original post by aksdj

is anyone revising as content?

I retook both as exams this year feel free to ask me anything 😀

Reply 1002

Daniel9998

Original post by tayloryeah

the kill switch is synthetically produced and placed into assassin cells, 'switch' in general refers to gene regulation.
I think this is the paragraph related to cancerous cells, so from that thought; cancerous cells release chemicals which stimulative the synthetic pathway in assassin cells to produce a transcription factor which binds to the promoter region of DNA, activates the gene coding for enzymes (via transcription and translation) which secretes apoptosis, ie. self suicide of the cell

insta @abcdefghijkleila_

wtf are we supposed to know **** like this, feels like im studying a complete different exam board

all ive been using is the cgp A2 book, which im now starting to regret

Reply 1003

aksdj

Original post by Ikran

I retook both as exams this year feel free to ask me anything 😀

Can you remind me how statins work ^^

Reply 1004

HasanAlam

Original post by tayloryeah

Does the chemical from the cancerous cell stimulate the production of transcription factors or does it bind to existing transcription factors causing them to become activators?

Reply 1005

Daniel9998

Looks like im just gonna wing the pre release, its all about confidence (thats what I keep telling myself).

Reply 1006

Ikran

Original post by aksdj

Can you remind me how statins work ^^

Statins are drugs which lower the cholesterol level which inhibit the Enzymes involved in LDL production

Reply 1007

LUCYDS

Original post by tayloryeah

Thank you so much! i have no idea what this article is going on about tbh

Reply 1008

TheITDept

So I'm super screwed for tomorrow... it was nice knowing y'all >_<

Reply 1009

alexfrances

can someone please tell me if in oxidative phosphorylation is ATPase used or ATP Synthase cause my textbook and revision guide is saying synthase but the mark scheme is saying ATPase

Reply 1010

Siberiaan

bit confused by controling heart rate questions:

Textbook is talking about releasing adrenaline to stimulate san contraction , but the m.k scheme talks about barorecptors detecting change due to blood ph falling , indicates high co2 , sends impulses to medulla etc

Which one is right :L

Also textbook includes stuff about body's response to extreme temperatures over long periods of time

- Thyroxine is released
Travels to nucleus and switches on genes which are responsible for encoding respiratory enzymes
-more mitochondria produced increases rate of aerobic respiration

Hormones TRH relased- never seen q about this in papers :l

Reply 1011

LThomas694

Original post by alexfrances

can someone please tell me if in oxidative phosphorylation is ATPase used or ATP Synthase cause my textbook and revision guide is saying synthase but the mark scheme is saying ATPase

You can write either it doesn't matter, they're both correct

Posted from TSR Mobile

Reply 1012

forestspirit

Original post by alexfrances

can someone please tell me if in oxidative phosphorylation is ATPase used or ATP Synthase cause my textbook and revision guide is saying synthase but the mark scheme is saying ATPase

ATPase refers to a group of enzymes, some of which are involved in ATP synthesis during chemiosmosis but mostly used in hydrolysis of ATP. The presence of hydrogen ions (H+) in the stalked particle (next to the electron transport chain in the inner mitochondrial membrane) changes the shape (conformational change) of the ATPase enzyme's active site, allowing ADP to bind to the active site in ATP synthesis.

Reply 1013

tayloryeah

Original post by Daniel9998

wtf are we supposed to know **** like this, feels like im studying a complete different exam board

all ive been using is the cgp A2 book, which im now starting to regret

the point of the pre release is to expand our knowledge at the same time as showing application of our A2 knowledge, all that is mentioned is in our spec but in the context of the pre release :smile:

Reply 1014

aksdj

Original post by Ikran

Statins are drugs which lower the cholesterol level which inhibit the Enzymes involved in LDL production

thank you !

Reply 1015

aksdj

Original post by Ikran

Statins are drugs which lower the cholesterol level which inhibit the Enzymes involved in LDL production

thank you!

Reply 1016

tayloryeah

Original post by TSR Mustafa

i would follow the mark scheme, the text book tends to waffle, and the stuff that comes up in the mark scheme repeats with question like these. although adrenaline does affect the activity of the SAN when it is secreted from the adrenal gland but that occurs when there is changes in CO2 of which the SAN activity needs to increase to increase the frequency of depolarisation through the atrial walls and thus the cardiac output increases to allow oxygenated blood to be carried through blood vessels. Baroreceptors are related to changes in blood pressure, they are located in the aortic and carotid arteries, if blood pressure drops, impulses are sent to the medulla oblongata to the cardiovascular centre which coordinates a response by sending impulses through the sympathetic nervous system to increase the heart rate, so that the arteries lumen constrict to increase blood pressure.

the only thing you need to know about temperature is thermoregulation regulated by the hypothalmus located in the brain. and the only thing you need to know about thyroxine is that it is a hormone just like adrenaline

(edited 7 years ago)

Reply 1017

PhysicsIP2016

Original post by TSR Mustafa

Both are correct for the heart rate one, it's just that adrenaline is the hormonal response due to the change in blood pH while the nervous response is the impulses sent from the medulla.
I've never seen specific questions about thyroxine but make sure you know generally about hormonal responses and how they can trigger transcription initiation complexes to bind to the promoter regions etc. to cause chemical changes.

Reply 1018

fpmaniac

Original post by tayloryeah

the point of the pre release is to expand our knowledge at the same time as showing application of our A2 knowledge, all that is mentioned is in our spec but in the context of the pre release :smile:

Whats the point of preparing questions for the pre release though. Questions in the actual exam are going to be random anyways so I dont see the point