Ch. 4 cell structure Flashcards
Define Prokarya
Before nucleus
Define Eukarya
“True” nucleus
When were cells discovered?
In 1665 by Robert Hook
What is Cell Theory? (hint there’s 3 answers)
1) All organisms are composed of cells
2) cells are the smallest living thing
3) cells arise from pre-existing cells
What’s a resolution?
The minimum distance that 2 points can be apart and still be distinguished as 2 separate points
What are the 4 types of microscopes?
1) light - use magnifying lens and visible light
2) electron - use beams of electrons
3) transmission electron - transmit electrons through materials
4) scanning electron - beam electrons onto surface of specimen
What are the 4 basic structure similarities of all cells? In other words, what do all cells have?
1) DNA
2) Ribosomes
3) cytoplasm
4) plasma membrane
What is Cytosol?
Liquid component of cytoplasm
What do prokaryotes (archaea and bacteria) lack?
A nucleus
What did Robert Hook call cells?
Cellulae
What did Matthias Schleiden discover in 1838?
That cells make up the tissue of plants
What did Anton van Leeuwenhoek call cells?
animalcules
What did Theodor Schwann discover in 1839? What did it lead to?
Cells make up animal tissues which led to cell theory being born
What’s Cell Theory?
The explanation for the observation that all organisms are composed of cells
What’s the Modern form of Cell Theory? (there are 3 parts)
1) all organisms have 1+ cell in which metabolism and heredity occur w/in these cells
2) Cells are the smallest living thing and the basic unit of organization of all organisms
3) Cells arise from division of pre-existing cells
What’s the surface area-to-volume ratio?
As a cell’s size increases, its volume increases more rapidly than its surface area
What’s a compound microscope?
One that magnifies in stages using multiple lenses and resolve structures more than 200 nm apart
What does Immunohistochemistry use?
Antibodies to bond to specific proteins after being chemically bonded
What are prokaryotes?
simplest organism that primarily has a single circular molecule of DNA found in the nucleoid
What are eukaryotes?
Have DNA organized into linear chromosomes segregated into a nucleus
What’s the difference between a prokaryote and a eukaryote?
Pro: has nucleotide
Euk: has a nucleus
What’s cytoplasm?
Semifluid matrix that fills the interior of the cell
What’s a ribosome?
large macromolecular machines made of RNA and protein that synthesizes all cellular proteins
What’s the plasma membrane?
an enclosure of a cell that separates its contents from its surroundings
What’s a plasmodesmata (in plants)?
Where plants are connected in the cell walls
What’re flagella?
a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility
What’s a gap junction?
intercellular connections between a multitude of animal cell-types. They directly connect the cytoplasm of two cells, which allows various molecules, ions and electrical impulses to directly pass through a regulated gate between cells
What’re tight junctions?
Leak-proof seals that surrounds an epithelial cell
What’s an Adherens junction?
cell-cell adhesion complexes that are continuously assembled and disassembled, allowing cells within a tissue to respond to forces, biochemical signals and structural changes in their microenvironment
What is a Bacterial Microcompartment (BCM)?
something that isolates a specific metabolic process or stores a particular substance