Month: November 2017

B1 is a very important subject as it covers the basics in Biology. We’ve been studying B1 for the past few weeks and here are the Top 5 things people should know from B1 Characteristics of cells.

1. Life

Life is the very important, as without it, we wouldn’t have what we have today. Although there are any definitions of life, life to me is that life is the differentiation between animals and plants from inanimate objects. All living objects must fulfil a set of requirements in order to be considered as “living”. The 7 characteristics of living things are called MRS GREN which are initials for movement, respiration, sensitivity, growth, reproduction, excretion and nutrition. Movement is when an organism changes place or position. Respiration is the chemical reaction that breaks down the nutrients in the sells of living organisms to give energy. Sensitivity is the ability to sense changes in surroundings and respond to it. Growth is a permanent increase in size and dry mass (when an organism is dead and there is no water in the organism) which can be measured by the growth of cell size and/or cell number. Reproduction is the making of more organisms that are the same species. Excretion is the release of toxic and waste materials from an organism. Nutrition is the use of minerals and organic substance in an organism in order to sustain it.

2. Cells (In the Human body)

All living things are made out of cells. Cells are the very basic building blocks of life. They have many functions in our body and they all work in sync to keep us healthy and alive. The red blood cell is a good example of how cells have different responsibilities in our bodies. The red blood cells carry oxygen around our body because all the cells in our body require oxygen. The red blood cells contain haemoglobin which helps carry oxygen. There is no nucleus in the red blood cells and they are shaped in a way that it carries a lot of oxygen to make it efficient.

3. Animal and Plant cell

Animal and Plant cells are quite similar to each other while being different in some areas. Both the plant and animal cell have a nucleus where everything that happens in the cell is controlled by, a cell membrane that decides what goes in and out and the cytoplasm where all the chemical reactions occur. The plant cell has extra components like the vacuole which contains water to keep the shape of the cell. Chloroplasts store the sun’s energy which is used in photosynthesis. Plant cells have an additional layer called the cell wall which makes the cell strong.

4. Diffusion

Diffusion is the net movement of molecules from a region of high concentration to a region of low concentration down a concentration gradient as a result of their random movement. An example of diffusion would be when Mr. Barnett told the class to stand in a line and sprayed air freshener from one end of the line. As the air freshener particles diffused, it moved from a region of high concentration (where Mr. Barnett sprayed it) to a region of low concentration (the other end of the line). Gradually the whole class could smell it as it diffused down a concentration gradient.

5. Osmosis

Osmosis is basically diffusion, but through a semipermeable membrane and has to do with water. A definition for osmosis would be the movement of water molecules from region of high water concentration to a region of low water concentration. An example of osmosis would be our potato experiment. What we had to do was cut pieces of potato and leave it in 5 different sucrose solutions. After a while, the potato would either increase in mass due to water entering through it’s semipermeable membrane or it would decrease due to water leaving the potato through the semipermeable membrane and into the solution. This happens because the solution was either a hypertonic solution in which case the potato had a higher water concentration and would decrease in mass or a hypotonic solution meaning that the solution has a higher water potential than the potato, resulting in water to enter the potato through the semipermeable membrane causing it to increase in mass.  

Starting off as a new student, in a new school, and in a new living environment is a bit tricky. After the first half the my first term in 9th grade my ATLs cam out and it was good. I am satisfied with my ATLs. As my mentor said most of them were around clear as it was just the start of the year because we were just starting to get to know our teachers. I didn’t get any some or concerned, so I think I should be fine. I got a few strong , so I should try and keep it up. When I look at areas for development, I saw that I should work on collaboration a lot of times. I think collaboration has been something I did not do very well at because I don’t know a lot of people and I just try to sit back and listen. I think I should try contributing a bit more in the coming half of the term.