1.1 - Cell introduction Flashcards
What features do all cells have?
- Cell (plasma) membranes
- Genetic information
- Ability to carry out chemical reactions
- Cytoplasm
- Ribosomes
- Energy release system
What are the 3 components of the cell theory?
- Living organisms are made up of one or more cells
- Cells are the smallest units of life
- All cells come from pre-existing cells
Who was the first person to use the term ‘cell’ and use a microscope to examine cork?
Robert Hooke (1635-1723)
Who was the official discoverer of cells who observed single-celled organisms?
Antonie van Leeuwenhoek (1632-1723)
How is a skeletal muscle an exception of the cell theory?
Made of fibres much larger than normal cells + contain many nuclei
How is fungal hyphae an exception of the cell theory?
Has many nuclei in long threads
How are giant algae an exception of the cell theory?
They are uni-cellular but associate with other cells in a matrix
What functions do all cells carry out?
- Metabolism
- Reproduction
- Homeostasis
- Excretion
- Response
- Nutrition
- Growth
(MR HERNG)
Name two key points to remember about SA to V ratio.
- SA to volume ratio gets smaller as a cell grows larger.
- Organisms become larger and multicellular so cells can divide
The rate at which a substance crosses a membrane depends on _____.
Surface area
The rate of reactions is proportional to the ____ of a cell.
Volume
Name 3 special features of stem cells.
- Unspecialized
- Can divide repeatedly
- Can differentiate into several cell types
What are the names of both types of stem cells?
- Embryonic stem cells
- Adult stem cells
Name one medical use of a stem cell.
Embryonic stem cells treat Stargardt’s disease, which leads to macular degeneration and blindness.
Why do some people think that stem cell research is unethical?
The use of embryonic stem cells can involve early-stage embryos
