Lecture 1: Biom1050 r485x

BIOM1050: Lecture 1 (3/3/16) What is life: How can we tell the difference between an organism that is alive and an organism that is not (class discussion);     

Respires/ breathing: Takes items from the environment and expels others (organisms that are not alive do not produce change in the environment). Changes and responds to its environment. The ability to metabolise: Transforms food and water from the environment through energy conversions and uses it for chemical work or physical work. Living organisms have to capacity to reproduce and transmit something into another code of itself. Creates change (goes through independent change: can generate change within itself, unlike non-living organisms which changed through the environment).

Living things can be recognised by what they do. Living things have:     

A complex order Adapt to environment Respond to environment Grow Reproduce

Living this are organised into biological hierarchies. Such levels range from the whole planet such as they ecosystem, biosphere and communities through to the molecules that make up our cells. Our focus in this module is cell biology and biochemistry (the blueprint of molecules - cells and DNA). People thought protein contained the code and DNA was structural. DNA is the central molecule of life. DNA constitutes the heritable information molecule in cells. Genes are encoded on DNA and are used to encode proteins. DNA encodes the messages that are needed to create an organism - you cannot make an offspring organism without using and packaging the DNA into the offspring. We are vehicles of nucleic acid. How does information get from the DNA to the rest of the cell: To get from gene to protein, the cell produces an intermediate molecule called mRNA in a process called transcription. The cell then uses this mRNA to produce a protein in a process called translation. Transcription - The process of reading DNA and making RNA. Translation - The process of getting MRNA (messenger) and forming a protein. Eukaryotic cell and Prokaryotic cell (Eukaryote process messenger RNA before it is translated). Processed RNA is then used to make a protein. Prokaryotic cells are extremely important too living organisms and are very related to the proteins needed/ found in humans. KEY CONCEPT:

There are 2 kinds of cells and there are similarities and differences between each. Different types of organisms have different types of cells. Plant cells have vacuole, chloroplast and cell wall and animal cells do not (only have a membrane). Bacteria cells do have a cell wall (different levels of thickness)

The picture above Picture is of a eukaryotic and prokaryotic cell. An Animal’s cell (eukaryotic) can vary in shape as there is no cell wall, thus it is super flexible. The prokaryotic cell has a rather thick cell wall, thus has a rigid shape. The nucleic acid is found in the nucleus of the eukaryotic cell. The chromosome in the prokaryotic is 'naked' as it is not surrounded by anything (no membranes/ nucleus). Each organelle in the eukaryotic cell has a membrane whilst the prokaryotic cell does not. Prokaryotic cells are extremely well adapted to particular jobs. 'Eu' in Eukaryotic is defined as 'with a nut' and Pro in prokaryotic is defined as 'before the nut'. Note* take look at the types of cells before the workshops next week. Prokaryotic is simple but still contains the same basic internal structures as eukaryotic cells. Similarities: All have membranes - Eukaryotic has more than prokaryotic. The membrane around the outside is known as the plasma (euk) or the cell membrane (pro). They all have a cytoplasm - Prokaryotic contains the DNA floating in it. Eukaryotic - is broken up within the cell. All have proteins and carbohydrates - secreted by cells into the medium around them. Proteins:    

Transport (act as motors). Defence (recognise incoming threats). Secreted outside of the cell. Communicate (act as messengers - they can be secreted or displayed).

Carbohydrates:   

Energy sources. Scaffolding (rigidity - maintaing shape) Messengers

All cells have metabolism and RNA, DNA, membranes (different types)