cell structure and function study guide KEY Flashcards
What are the three parts of cell theory?
All living things are made of cells
Cells are the basic unit of structure and function
All cells come from existing cells
Who was the first person to see and name cells?
Robert Hooke
Prokaryotes:
no nucleus
no membrane-bound organelles
small and simple
Ex: bacteria
Both Prokaryotes and Eukaryotes:
ribosomes
DNA
cytoplasm
cell membrane
Eukaryotes
nucleus
membrane-bound organelles
large and complex
Ex: plants and animals
What are three major differences between plant and animal cells?
Plants have cell walls, animals do not
Plants have chloroplasts, animals do not
Plants have a large central vacuole, animals have many small vacuoles
Nucleus
contains DNA, controls cell activities
Nucleolus
makes ribosomes
Ribosome
produces proteins
Mitochondria
uses glucose to generate cellular energy (cellular respiration)
Vacuole
stores water and materials
Cell Membrane
controls what enters and exits the cell
Cell Wall
supports and protects plant cells
Chloroplast
produces energy from sunlight
Cytoplasm
jelly like substance that fills the cell
Lysosome
contains digestive enzymes - digests wastes in the cell
Endoplasmic reticulum (smooth & rough)
smooth produces/modifies lipids, rough produces/modifies proteins
Golgi apparatus
modifies and packages materials for transport
Cytoskeleton
help give the cell structure.
Describe the basic structure of a cell membrane. Be sure to include the words: phospholipid, hydrophilic, hydrophobic, & proteins.
The cell membrane is made of a phospholipid bilayer. Each lipid has a hydrophilic head and two hydrophobic tails. There are also proteins embedded in the membrane.
What is diffusion?
Diffusion is the movement of molecules from an area of high concentration to an area of low concentration. It does not require energy.
What is the major difference between diffusion and facilitated diffusion?
In diffusion the molecules go directly through the lipid bilayer in the cell. In facilitated diffusion the molecules go through proteins in the membrane. Facilitated diffusion is used for large or charged particles.
What is osmosis?
Osmosis is the diffusion of water through a semipermeable membrane. It does not require energy.
What would happen to a cell that was placed in each of the following solutions?
Hypertonic- water flows OUT of the cell and the cell will shrivel
Hypotonic- water flows INTO the cell and the cell will swell and possibly burst
Isotonic- water will flow IN and OUT of the cell equally. The cell will remain the same.
How is active transport different from diffusion and osmosis?
Active transport requires the use of energy and goes from low to high concentration. Diffusion and osmosis do not use energy and go from high to low concentration.
How do you calculate total magnification on the microscope?
Ocular lens x objective lens
If a microscope has a 10x ocular lens, what would be the total magnification using the following objectives? (show your work)
5x objective- 10 X 5 = 50x
10x objective- 10 X 10 = 100x
50x objective- 10 X 50 = 500x