Test 1 (Cell Theory) Flashcards
What is magnification?
How large an image is.
What is resolution?
The ability of the microscope to show two close objects separately. (How clear the image is)
What are the kingdoms of life?
There are 6 kingdoms of life and they are; archaea (prokaryotes), monera (prokaryotes), protista (prokaryotes and some eukaryotes), fungi (eukaryotes and some prokaryotes), plantae (eukaryotes), animalia (eukaryotes).
What is cell theory?
The three key concepts of cell theory are:
- Cells are the smallest units of life
- Cells can only come from existing cells
- All living organisms are made of cells
Who proposed cell theory?
- Schleiden: German botanist
- Schwann: German zoologist
- Virchow: German pathologist
When was cell theory proposed?
It was proposed in the late 1830’s
What are the 3 main parts of all cells?
The three main parts of cells are:
- Cytoplasm
- Organelles
- Plasma membrane
What are the benefits of using a light microscope?
The benefits are:
- Real color can be seen
- Field of view is large enough to see whole organism
- Easy to prepare sample
- Living material can be observed
What are some things about electron microscopes?
- Great resolution and magnification that shows the ultrastructure of a cell
- Preparation is lengthy
- Material to be observed is dead
What are the sizes of most plant and animal cells?
They are between 10-100 micrometers
What are some exceptions to the cell theory?
- Skeletal Muscle: They are 300 mm long or more (breaking the SA:V ratio, and they have hundreds of nuclei)
- Giant Algae: They only have 1 nucleus and can be 100 mm long
- Aseptate Fungi: Made of thread like structures called hyphae. They are long undivided parts of hyphae that have many nuclei
What are the functions of life in unicellular organisms?
They are:
- Homeostasis (keeps internal conditions within limits)
- Response
- Metabolism
- Growth
- Reproduction
- Excretion
- Nutrition
How do you calculate magnification?
To find magnification: take the length of the scale bar that you measured and divide it by the length shown on the scale bar.
OR
Take the size of the image and divide by the size of the specimen
How do you calculate actual size?
To find actual length: take the measured length of the image and divide it by the magnification
OR
take the length of the image and divide it by the measured length of the scale bar and multiply the answer by the scale bar unit
What are the SI units?
- Tera (T): 1,000,000,000,000 - 10 to the 12
- Giga (G): 1,000,000,000 - 10 to the 9
- Mega (M): 1,000,000 - 10 to the 6
- Kilo (k): 1,000 - 10 to the 3
UNIT (Joules, grams, meters, etc…)
- Deci (d): 0.1 - 10 to the -1
- Centi (c): 0.01 - 10 to the -2
- Milli (m): 0.001 - 10 to the - 3
- Micro (u): 0.000001 - 10 to the -6
- Nano (µ): 0.000000001 - 10 to the -9
- Picto (p): 0.000000000001 - 10 to the -12
What is an emergent property?
Emergent properties are properties that arise from the interaction of the component parts of a complex structure. Multicellular organisms have properties that emerge from the interaction of their cellular components.
What is an example of an emergent property?
Cells - tissues - organs - organ systems - organisms
Muscle cells and epithelial cells- muscle and epithelial - esophagus, stomach and small intestine - digestive system - human
What is differentiation?
It is when the cells express or don’t express parts of the genome so that the stem cell can become a certain type of cell. Once a cell has started to differentiate, it is said to be committed and cannot change into another cell.
What is a stem cell?
A stem cell is a cell that has the capacity to divide and differentiate along different pathways.
Human embryos are made entirely of stem cells and gradually commit into differentiation. Once the cell has differentiated, it will always divide as that type of cell.
Where are stem cells found?
They are found in embryos, which have the power to differentiate into any cell. They are also found in bone marrow, liver and skin, although they can’t become any cell.
What are some pros for the ethics of stem cell use?
They are:
- The lives of the people that will be treated will be improved
- The embryos are not live yet, just balls of cells
- They don’t have a nervous system yet, so they do not feel pain
- Many embryos that are made for IVF are never used, to they will never experience life.
What are some cons about stem cell use?
People say that it is a life, and it should get the chance to live
What can stem cells be used to treat?
Stargardt’s macular dystrophy: Genetic disease that is in children 6-12. Due to a recessive gene. The cells in the retina can’t get nutrients, so they die. They take embryonic stem cells that have been differentiated into retina cells and inject them into the retina of the patient.
Leukemia: Type of cancer where there a lot of white blood cells produced in the bone marrow. They take a needle and get bone marrow from the hip. They take the stem cells out of the bone marrow, freeze them and then give the patient chemotherapy to kill the cancer cells. They then return the stem cells beck to the bone marrow.
What is a Transmission Electron Microscope (TEM) used for?
They are used for viewing the ultra thin sections of a cell, which is also known as the ultrastructure of a cell, of the organelles inside of it.
