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Four bases is correct. The complementary nature of these bases underpins how the DNA release genetic information for the cell's uses and perform DNA replication. It is more correct to say three bases (called a "triplet" on the DNA strand) "code" for an amino acid. The sequence of bases in the...

Perhaps it is best if you read the introduction in textbooks and the Contextual Outline in the Syllabus, if you have not already. That should give you a general feel of what the module is teaching. Anyhow, a small overview: The Blueprint of Life module examines the processes required to...

From (my bad) memory, proto-oncogenes are genes that code for growth factors for a cell. If they mutate, they become carcinogenic oncogenes and may produce excessive growth factors, resulting into unrestrained cell growth/multiplication and ultimately into a tumour. Something like that...

When the electrons are unimpeded, thats superconductivity.

The temperature prac is essentially the same as the pH prac. A optimum level (of pH or temperature) for maximum enzyme activity, any deviations result in reduced activity rate, any larger deviations result in no activity at all because it will denature the enzymes. So, it will be a bell-shaped...

Polypeptide chains (usually several) fold together three dimensionally to form a protein. Hence, polypeptide synthesis is a step in protein synthesis (protein synthesis takes several of these polypeptide chains to form the protein).

Those unemployed are: - People aged 15 or over, and - Have not worked the previous week, but have been actively looking for work in the previous month and are ready to work next week.

Thats more like it :) But as I referred to before: Specifically it is the killer T cells that 'release substances to destroy antigens'. Other T cells serve a different purpose: eg. suppressor T cells halt the cell-mediated immune response. So perhaps your listing of the types of T cells...

Just some brief notes. You may wish to do some research to be able to expand on it. You can consider dogs and bats as the 'two other mammals': - Most nocturnal bats emit high frequency sound waves and use the echo to gain information about its surroundings (a process called echolocation)...

Also, neutron bombardments wont apply here because neutrons are uncharged and thus wont be subject to electrostatic interactions as alpha particles would.

Probably since gold has high density (more positive nucleus per unit of space), the probability of interactions (deflections) between the nucleus and alpha particles is higher than other materials (remember, the size of the nucleus takes up very little of the atom and so most will past through...

Not quite correct... 1. Phagocytes belong to the second line of defense. 2. Plasma cells ARE NOT phagocytes! Plasma cells are differentiated B cells, which are lymphocytes. An example of a phagocyte is a macrophage. 3. Lymphocytes can be divided into T and B cells. 4. Specifically, it is...

I have no idea then. The "txxxxxx" is probably something made redundant/improved because of the dark environment of nocturnal animals. Yeah, I guessed sclera because it connects to the cornea and goes all the way to the back. I still dont understand the wording of the question though.

1. I dont really get the question, but I dont think the retina is connected to the cornea. My guess is the sclera (Im a bit rusty - is this word the right one?). 2. I believe its the rods (edit: sorry, I accidentally wrote cones before).

Pass rays of light through different thicknesses of convex lenses (actually, it is the slope of the lens at which the incident light enters and exits that matters - but when you have a 'fatter' lens, generally the slope is indeed more steep). You will find different sizes of lens would produce...

a) No, it is the B lymphocytes (to be specific: plasma cells) that produce antibodies. b) Yes, T helper lymphocytes activates and stimulates other cells to begin the antibody/cell-mediated immune response. c) No, B lymphocytes produce antibodies, not antigens. It is pathogens that provide...

T cells certainly do act against 'free antigens' (I take it as antigens 'floating around' in the system), but we are discussing whether free antigens will provoke the immune response. jims is probably right. You will need antigen-presenting cells to activate T and B cells. That is, to...

There are many types of T cells. You should specify. Anyway, helper T cells is indeed 'activated' by (free?) antigens. Other types of T cells, such as killer and memory, I would think not, instead by activated helpers. I always thought the B cells are activated by activated helper T cells...

The powered-on transmitter produced radio waves (electromagnetic radiation) which induced a potential difference between the gap in the loop. Putting the loop sufficiently close to the transmitter created a large enough potential difference to make the electrons jump from one end to the another...

Braggs' X-Ray diffraction experiment was to determine the structure of a crystal, by analysing the diffraction patterns when X-Rays bombard it. To determine the formula (where d = interatomic spacing of the crystal), suppose two synchronised X-Ray waves are fired at the crystal, and each...