BLOG BY ANDRES ERASO AND SARA MIRA

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.

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. 

MEIOSIS vs. MITOSIS

Definition	MEIOSIS A type of cellular reproduction in which the number of chromosomes are reduced by half	MITOSIS A process of asexual reproduction in which the cell divides in two producing a replica.
Function	Make cells genetically diferent by sexual reproduction.	Cellular reproduction.
Type of Reproduction	Sexual	Asexual
Occurs in	Humans, animals, plants, fungi.	All organisms.
Genetically	Different	Identical
Creates	Sex cells only (female egg male sperm)	Makes everything other than sex cells.