Cell Theory & Technology Flashcards
(History) What is the Scientific Method?
Observations -> Question -> Hypothesis -> Prediction -> Test
If supports H, make additional P
If doesn’t support H, revise H
(History) What are the list of 5 things that are characteristic to all living organisms?
- need energy
- produce waste (nothing is 100% efficient)
- respond and adapt to the environment
- able to reproduce
- able to grow
(History) Explain abiogenesis.
AKA spontaneous generation. Aristotle’s theory was accepted for over 2000 years (his theories impeded chemistry and biology!)
Abiogenesis: the idea that living things can arise from non-living things.
Ex: rats from garbage, maggots from rotting material, eels from slime in river mud, mice from pile of wheat husks
His theories are were based on his observations, but didn’t conduct any scientific materials to test his idea.
(History) Who was Francesco Redi?
Used controlled scientific experiments to refute the idea of spontaneous generation.
Maggots appeared in the open jars because flies had access to lay eggs on the meat, not because the meat produced maggots.
(History) Who was Louis Pasteur?
Scientist who finally settled the continued debate of the theory of spontaneous theory.
Hypothesis: air has microbes/germs
A flask of nutrient rich broth was boiled, air forces out, to kill microbes. Flask cooled was cooled and broth was clear. Microbes settled in the bend of the swan-neck tube (gravity). When flask was tipped, the broth became cloudy, as microorganisms settled in the neck went into the broth.
(History) What did Pastuer and Virchow do in 1858?
Proved biogenesis.
(History) What is biogenesis?
Living organisms can only arise (come) from another)
What is a cell?
The smallest functional unit of life, found in all living organisms
(History) Who was Robert Hooke? (1635-1703)
Looked at cork under a compound microscope (30x magnification) and was the first to name and see “cells”. It features drawings mostly of insects such as flees.
(History) Who was Anton van Leeuwenhoek (1632-1723)?
A Dutch merchant who first described single-celled microorganisms. He used a single-lens microscope (500x magnification) to study blood cells, pond water, and teeth scrapings. He named it “animalcules”.
(History) Who was Matthias Scheleiden (1804-1881) and Theodor Schwann (1810-1882)?
Scheleiden studied plants and Schwann studied animals.
Their research contributed to cell theory stating that “all organisms, plants, and animals, were composed of cells.”
They still believed in abiogenesis, though.
Who was Rudolf Virchow (1851-1902)?
Made microscopic observations of cells dividing and completed cell theory.
“Cells can only arise from other cells”.
What are the three main points of cell theory?
- All organisms are composed of one or more cells
- The cell is the smallest functional unit of life
- All cells are produced from other cells
(FYI) What are light microscopes and electron microscopes?
LM: One or more lenses that make an enlarged object of an object.
1. Simple Microscope (only 1 lens, like a magnifying glass)
2. Compound Microscope (2+)
EM: Uses a beam of electrons instead of a beam of light to magnify the image. No colour.
1. Transmission Electron Microscopy
2. Scanning Electron Microscope
3. Confocal Laser Scanning Microscope
4. Scanning Tunnelling Microscope
Review what each of these parts of the microscope is/does.
- Eyepiece/Ocular Lens
- Tube; keeps lenses right distance apart
- Coarse-Adjustment Knob
- Fine-Adjustment Knob
- Arm
- Revolving Noisepieces
- Objective Lenses
- Stage
- Stage Clips
- Diaphragm
- Light Source
- Base
