Cells and Microscopes Flashcards
Who made the first compound light microscope
Janssen (late 1500s)
What did Leeuwenhoek do
improved magnification
first to observe living cells under microscope (called them animalcules)
Simple microscope vs. compound microscope
Has only one lens vs. two lenses
Electron microscopes
use electrons instead of light
magnify up to 1,000,000 X
high magnification and resolution
Cells must be dead
SEM
scanning electron microscope
produces 3D image
Only see surface of specimen
TEM
transmission electron microscope
Produces 2D image
Can see detailed cell parts
STM
scanning tunneling microscope
Shows arrangement of atoms and molecules
Can observe live specimens
What are the three parts of cell theory
- Cells are the smallest unit of life
- All living things are made of cells (at least one)
- All cells divide and come from pre-existing cells
Centrifuge
spins to separate mixtures (like cells)
Micro dissection
using tiny instruments under a microscope to work with cells
Cell culture
grow cells in a lab
The variety of cell shapes reflect
different functions
What is the boundary of the cell and what is it made of
plasma membrane (aka cell membrane) Made of a phospholipid bilayer
Cytoplasm
everything in cell except nucleus
cytosol - liquid part of the cytoplasm includes dissolved materials
Nucleus
Control center of the cell
DNA is inside nucleus in eukaryotes
DNA is free floating in prokaryotes
Ribosomes
make protein.
Start in cytoplasm. Some will sit down on rough ER.
Prokaryotes
have no nucleus or membrane bound organelles Have plasma membrane Have cell wall Have ribosomes Have free floating circular DNA
Eukaryotes
Have nucleus and complex membrane bound organelles
Cellular organization small to large
cell tissue organ organ system organism
Plant cells
Have large central vacuole
Have cell wall
Have chloroplast
Define organelle
subcellular structure that has one or more jobs to perform in the cell
Cells are limited in size by
rate at which substances needed by the cell can enter through the surface
Want the largest surface area to volume ratio possible
Diameter of most plant and animal cells
10 - 50 micrometers
How does a nerve cell illustrate that structure is related to function
long extensions for sending impulses
How do skin cells illustrate that structure is related to function
skin cell are flat and form a barrier
How are organelles in a cell like organs in an organism
organelles all have different jobs but work together to keep the cell functioning this is the same as organs in an organism
When were microscopes first used
17th century
Ribosomes
make proteins
Rough endoplasmic reticulum
has ribosomes
modifies proteins
moves proteins through ER and into Golgi apparatus (golgi body)
Golgi Apparatus or Golgi Body
Modifies and packages proteins into vesicles
Vesicles
Transport proteins or other materials around the cell
Smooth endoplasmic reticulum
makes lipids
removes toxins from the cell
Cell wall
made of cellulose
provides structure and support to plant cells and fungi
Mitochondria
turns glucose into ATP
Chloroplast
Captures sunlight and transforms it into chemical energy (glucose)
lysosome
contains enzymes that degrade old organelles, proteins, or the entire cell
Vacuole
storage of food, water, or enzymes
Centrioles
make the spindle during mitosis
What organelles are involved with protein formation
nucleus (turns DNA to mRNA) ribosome (turns mRNA into protein) Rough ER (modifies protein) Golgi Body (modifies and packages proteins) Vesicle (transports proteins)
Where can proteins go after they are shipped out in vesicles
plasma membrane (either to stay in membrane or get shipped out of cell)
lysosome (if there is a mistake and they need to be degraded)
other organelles
What organelles are involved with energy
chloroplast (capture light energy and transform it to chemical energy)
mitochondria (transform glucose to ATP)
What is the process called where cells take on specific jobs?
differentiation
