viernes, 16 de enero de 2015

CIRCULATORY - IMMUNE

- White blood cells, which are present in blood, work as antibodies eliminating wastes and other non-wanted staff.

- The lymph is in charge of transporting all the white blood cells throughout the lymphatic system, which is part of the circulatory system (image). Because of the white blood cells, the lymph works as a filter of wastes present in blood (antibodies). This is how the immune and the circulatory systems work together.


- When this relation does not work properly, there can be many results. One of them is that the amount of white blood cells decreases and this could lead to infections, and other sickness because of the lack of antibodies.


viernes, 17 de octubre de 2014

CELL THEORY

The cell theory is a theory developed in the XIX century. It is made up of 3 postulates:
1. All living things are made up of cells.
2. The cell is the basic unit of living things.
3. Living cells come from other living cells.

The history of this theory started when Robert Hooke, an English scientist, discovered the cell by looking at a cork through a microscope in 1665. After Hooke, in 1676 Anton Van Leeuwenhoek find out something he called “animacules”, that are living cells. Later, he discovered bacteria.

 Matthias Schleiden and Theodor Schwann discovered that plants (Schleiden) and animals (Schwann) were made up of cells, and with these discoveries, the first postulate was developed: All living animals are made up of cells. Later, they also said that cells are the basic unit of structure of every living thing. After those discoveries, Rudolph Virchow, discovered that all living things come from other living things; meaning that living cells come from other living cells (third postulate)


The development of the cell theory is a good example of scientific inquiry because throughout its history, all de discoveries were found out by scientific methods and scientific tools: the microscope. 
CELL CYCLE 


Is a process that includes three phases: Growth (interphase), Mitosis (nuclear division) and Cytokinesis (cytoplasmic division). Growth is when de cell grows preparing for the nuclear division, and G1, S and G2 happened (DNA duplication). In mitosis, duplicated chromosomes are split equally, and the cell prepares for the cytokinesis. In the cytoplasmic division, the cell finishes splitting and forms two identical cells.





CELL GROWTH 


All cells in a normal status are equal in size. This is because every time, something wants to enter the cell, it needs to go form de cell wall to the organelles. If the cell grew more, the distance between de surface area of the cell or the perimeter and the organelle will be longer and this will make things slower for every process.

miércoles, 15 de octubre de 2014

MITOSIS 


Mitosis is the process during cell cycle where chromosomes in the cell nucleus separate creation a replica.


MEIOSIS 



Meiosis is a type of cell division specially used for sexual reproduction that occurs in Eukaryotes (animals, plants and fungi) and also including both multi celled and single celled organisms.