Edexcel BIOLOGY Doubts!!!!

[Deadly_king]

It's like so confusing could u plz summarize it using any diagrams:s plzz

Well, I don't know for sure which parts you're not understanding.

Try here, it may help you.

Am sorry but I can't help with diagrams.

[The Golden Girl =D]

I don't take Bio but I hope these help :

http://www.tutorvista.com/content/biology/biology-iv/circulation-animals/ecg-electrocardiography.php

http://www.cbu.edu/~aross/APII/Heart-Lab.htm

I hope I helped :S

[-Cornea]

okii can anyone please let me know frm where i can get the biology a.s syllabus i actually don't know wht i should have to know in ecg iam just studying from the book =(

[Amii]

okii can anyone please let me know frm where i can get the biology a.s syllabus i actually don't know wht i should have to know in ecg iam just studying from the book =(

I tried attaching but it's taking ages 

anyway here is the link
http://www.edexcel.com/quals/gce/gce08/biology/Pages/default.aspx
Documents--->Specification

take care 

[Weaam]

Hey guys, if anyone has the May/June 2010 paper of biology, i need help on Q2b and 3a(ii)
I couldnt find it on the site but i have it as homework

[Master_Key]

Hey guys, if anyone has the May/June 2010 paper of biology, i need help on Q2b and 3a(ii)
I couldnt find it on the site but i have it as homework

What is the question? I dont have edexcel papers so tell me the question.

[Weaam]

What is the question? I dont have edexcel papers so tell me the question.

Well, the first is about a diagram so u cant answer it.
But the second says, Explain how the properties of a phospholipid contribute to the structure of the cell membrane.

[The Golden Girl =D]

Well, the first is about a diagram so u cant answer it.
But the second says, Explain how the properties of a phospholipid contribute to the structure of the cell membrane.

3indik scanner/camera if u do then take a pic of it and post it

[Weaam]

my scanner doesnt work

[The Golden Girl =D]

my scanner doesnt work

Camera , Mobile ..BB ..etc

[Weaam]

I know the writing isnt clear.
It says: (on the top) the diagram below shows the structure of the heart.
(under the picture) Suggest which stage on the cardiac cycle is shown in the diagram and give a reason for your answer.

[Deadly_king]

Well, the first is about a diagram so u cant answer it.
But the second says, Explain how the properties of a phospholipid contribute to the structure of the cell membrane.

Phospholipid consist of two main parts; a polar(hydrophilic) head and a non-polar(hydrophobic) tail.

This allows the membrane to line up in such a way that the head faces the aqueous medium while the tails are inside away from water.

[Amelia]

Guys I srsly need ur help in this ECG  it's killing me =(

I'll give a simple explanation. Simple according to me I hope it helps.

A electrocardiogram (ECG) is a recording of the electrical changes that occur in myocardium (it is the major portion of the heart consisting largely of Cardiac muscle tissue) during a cardiac cycle. Body fluids contain ions that conduct electric currents. Therefore, the electrical changes in myocardium can be detected on the skin's surface.  When an ECG is being taken, electrodes are placed on the skin are connected by wires to an instrument that detects the myocardium's electrical changes. Thereafter, a pen rises or falls on a moving strip of paper. The image below depicts the pen's movements during a normal cardiac cycle.
  (Ignore da formula)

When the SA node triggers an impulse, the atrial fibres produce an electrical change called the P wave. The P wave indicates the atria are about to contract. After that, the QRS complex signals that the Ventricles are about to contract. The electrical changes that occur as the ventricular muscle fibers recover to produce the T wave.

P.S - My dad rocks. . (Ok, that was too random. )

[obstacle26]

The graph below shows changes in the blood pressure in the aorta and the left ventricle during two complete cardiac cycles.
(a) On the graph, draw an arrow to show when the left atrioventricular (mitral) valve closes.
(b) Use the information in the graph to calculate the heart rate. Show your working.

Don't know how to calculate the heart rate (b) ,  anyone  explain
Markscheme says: (b) 60 ÷ 1.0 ; [accept equivalent calculations] = 60 beats per minute ; [accept range 60 to 64], but how does 60 beats come only pressure and time in seconds is given? Thanx in advance 

[Amelia]

Heart rate is the number of heartbeats per unit of time - typically expressed as beats per minute (bpm) - which can vary as the body's need to absorb oxygen and excrete carbon dioxide changes, such as during exercise or sleep.
Typical healthy resting heart rate in adults is 60–80 bpm