Seems small, doesn’t? Well, you still need to know it, and you need to know it perfectly, so we’re going to cover it here. Different tissues, organs and organ systems… all necessary for the AQA B2 exam. Ready? Then let’s take the plunge…
Cells make up all living creatures, from animals to plants. Cells have some very important structures and purposes, along with certain specialised cells – and of course, you need to know about this for the B2 exam. Ready? Then let us begin…
There are a couple of ways of measuring the distribution of organisms in an environment:
- The Quadrat
- The quadrat is a square grid. It contains smaller squares of an equal size, and looks something like the image on the left.
- The Transect
- A transect is a straight line between two points. A quadrat is then placed systematically or randomly along the transect. It would travel along a terrain something like the image on the right.
Enzymes – the specifically-shaped proteins that help break down food, catalysing the process of digestion. And of course, you need to know what they are for the B2 exam. Inevitable, eh? Here we discuss what enzymes are, specific enzymes, and uses of enzymes. And this is a biggy – summary at the end for those of you that don’t want to wade through the inevitable sea of text associated with this topic presented here. Ready to take the plunge? Here we go…
Mitosis is a form of cell division (not to be confused with meiosis!). This is the form of cell division that happens throughout your body (it happens in your toes, so it happens everywhere!)
But, how does it happen? Well: all of a cell’s genetic information is stored inside the nucleus. The cell needs to split to divide. Just before this happens, the nucleus ‘splits’ in half. However: there’s a problem: if the cell were to split now, both of the two new cells would only have half of the genetic information they require, and it wouldn’t work!
Instead, after the nucleus splits, every chromosome (piece of genetic information) duplicates. There are now two copies of each piece of information in the cell. A copy of each chromosome moves to opposite sides of the cell. The cell now contains enough genetic information to make two separate cells. At this point, the cell splits in two, creating two new genetically identical ‘daughter’ cells.
And that’s it!
Respiration is one of the essential processes of the body – it is the process by which energy is released from glucose, which is essential for life – and here’s a quick guide to the ins and outs of both aerobic and anaerobic respiration, all in time for the B2 exam!
Ever wondered how a smell moves from one side of the room to another? Here you can find out – by the process of diffusion! For a quick guide to diffusion (which is, of course, on the B2 exam), read on…
There have been and are many species on Earth, right from the beginning of life, about 3500 million years ago – some of these species became extinct, whilst others have evolved, adapted and flourished – much like humanity. Here I explore how species begin, evolved, and become extinct – and the fossil record that tells us all of this.
The genetics that we receive from our parents determine what we look like; eyes, hair, height, the whole lot is controlled by genetic information that you had from the moment you were conceived. But with the genetics you inherit, there can come some faulty genes; mutations and genetic disorders. In this topic I explore the world of genetics, inheritance and genetic disorders in relative depth.