L1 Intro to cells Flashcards
What are the 3 main domains that organisms are classified into?
- Bacteria
- Eukaryotes
- Archaea (together, prokaryotes)
What is the estimate on the number of different species and how many are described?
1 trillion different species on earth, but only 0.001% are described
What is the most abundant bacterium?
Pelagibacter ubique
What does the cell theory propose?
1) Multicellular organisms are derived from a single cell
2) Cells can obtain energy and utilise chemicals
3) Cells use hereditary information that is passed on to its progeny (offspring)
Who proposed the cell theory?
Theodor Schwann and Matthias Schleiden
What is the size of a bacterium?
1um
What is the size of a plant cell?
80-100 um
What are the general characteristics of cells?
1) Cells are able to obtain energy, either from light and/or chemicals
2) Cells are able to use available chemicals to grow and multiple
3) Cells contain hereditary information that is stored in each cell and passed on to its progeny upon cell division
What are the physical characteristics of cells?
- All cells are enveloped by a plasma membrane, which provides a physical barrier between the cell and its environment
- Hallmarks of eukaryotic cells are organelles such as nucleus, mitochondria, endoplasmic reticulum, Golgi, lysosomes, peroxisomes and chloroplasts (plant) and a cytoskeletal structure
Are vacuoles in bacterial cells?
Vacuoles are present in some bacterial and animal cells but are more prominent in plant cells
What is the central dogma?
A fundamental principle that describes the flow of genetic information within a biological system
States that the information stored in DNA is transferred to RNA, and then from RNA to protein
Explain the central dogma of molecular biology
1) DNA replication - Process of creating an identical copy of DNA
2) Transription - Process of copying genetic infomration from DNA into RNA (mRNA)
3) Translation - Process of using information from mRNA to build a protein at ribosomes
