- The biological meaning of the cellular nutrition, reproduction and interaction.
- Cellular nutrition (I): membrane transport of substances.
- Cellular nutrition (II): enzymes.
- Cellular nutrition (III): the metabolism; anabolism and catabolism in autotrophic and heterotrophic beings.
- Cellular reproduction (I): the cell nucleus: DNA, chromatin, chromosomes; haploid and diploid cells.
- Cellular reproduction (II): the cell cycle.
- Cellular reproduction (III): cancer.
- Cellular reproduction (IV): the stages of mitosis; its meaning and role in eukaryotic cells.
- Cellular reproduction (V): meiosis: main events; its meaning and role in eukaryotes' gametogenesis.
- Cellular interaction: biological meaning and examples in prokaryotic and eukaryotic cells.
| Genetic material | In all cells the genetic material is DNA bound to proteins and organised in chromosomes. Bacteria have one chromosome, while humans have 46 in each cell. Its function is to store, express and transmit to the offspring the instructions that tell how every cell and living being will be self-constructed and how will they work. |
| Mitosis | Cells with more than one chromosome, once they've synthesised a full copy of the whole set of chromosomes, have to carefully organise their division in order to produce two daughter-cells with exactly the same genetic information. Mitosis is the complex process whereby most eukaryotic cells tackle such a task. |
Membrane transport, cell nutrition and cell reproduction in an easy-to-understand language.
Watch this animation to learn the basics of the cell cycle.
The cell membrane
Learn the structure, behaviour and biological meaning of the cell's plasma membrane.
Diffusion
Learn how the molecules of fluids move freely, and which force drives their motion.
Osmosis
Learn how the process of osmosis can even out the concentrations of two solutions to either side of a partially permeable membrane.
Passive transport
Learn how some proteins of the plasma membrane can allow a free movement of molecules in and out the cell.
Active transport (I)
Learn how some proteins of the plasma membrane can pump certain substances through the membrane against the concentration gradient with some contribution of energy.
Active transport (II)
A more detailed view of the process of active transport through the Na/K pump example.
Endocytosis and exocytosis (I)
Learn how plasma membrane sacs can help to transport materials in bulk in and out the cell.
Endocytosis and exocytosis (II)
A more detailed view on the role of the endoplasmic reticulum, the Golgi apparatus and the cell's membrane lipid bilayer in the processes of exocytosis and endocytosis.
Mitosis (I)
The mitotic process explained through an animated movie. [Some key words: thread, coil, unwind, spindle, fiber].
Mitosis (II)
The central stages of mitosis in a microscopic movie.
Mitosis (III)
Another animated movie on mitosis, this time silent.
Meiosis
The meiotic process explained through an animated movie.
