L2: General Properties and Types of Cells Flashcards
Are all cells self-replicating
Not all cells
What does a cell (or anything) need to be self-replicating?
- set of instructions (ex: DNA)
- gather materials/energy sources (proteins)
- make parts
- transform energy
- pass on instructions to new replicates
- mechanism to read instructions
- have a container to keep everything together
What does the cell theory state?
- all organisms are made up of cells
- the cell is the fundamental unit of life
- cells come from pre-existing cells
- there is no life w/o cells
- the cell is the smallest unit of life
Generally, which are larger
- prokaryotes or eukaryotes?
Eukaryotes
What does the tree of life show?
Evolutionary relationships
Which of the three branches of life have the greatest biodiversity?
Bacteria
What are the three branches of life?
- Bacteria
- Archaea
- Eukarya
What is the endosymbiont theory?
- all cells are thought to have evolved from a universal ancestral cell (LUCA - last universal common ancestor) from 3.5-3.8 billion years ago
- Eukaryotes are thought to have evolved from one cell engulfing another cell (ex: endosymbiont)
How do bacteria reproduce?
Binary fission
How do archaea reproduce?
Binary fission
How do eukarya reproduce?
- cell division: mitosis
- sexual reproduction: Meiosis
What is an endosymbiont?
- engulfed prokaryotic cells
Which two organelles in Eukaryotic cells are thought to have evolved from an endosymbiont?
Chloroplasts and mitochondria
Why are mitochondria and chloroplasts thought to have evolved from an endosymbiont?
- double membranes similar to bacteria
- DNA is a circular chromosome
- DNA sequences are similar to bacterial genes
- grow and multiply by BINARY FISSION - independently of eukaryotic cell
- Have own ribosomes, synthesizes proteins, etc.
