Unit Two Flashcards
Cell membrane
Aka plasma membrane
In animals and plants
Regulates passage of H2O, ions, CO2, O2, and other molecules in and out of the cell
Cell wall
In plants only
Protects plant cell and provides structure
Cytoplasm
In animals and plants
Cell “gel” and organelles
Contains minerals, organic molecules, and gases
Just the gel = cytosol
Cytoskeleton
In animals and plants
Connection of fibers that allow organelles/molecules to move around cell
Microfilament, intermediate filaments, microtubules
Microfilament
(Actin filaments), two protein chains twisted together
Movement
Intermediate filaments
More ropelike, STRONG
Cell shape and anchor organelles
Microtubules
Straight hollow tubes
Tracks for organelle/molecule movement
Cilia and flagella
Centrioles
Animals only
Microtubule triplets involved in cell division (mitosis)
Looks like two dynamite sticks crossed or multiple
Nucleus
In animals and plants
Holds DNA (genetic information)
Usually one of largest structures
Includes nuclear membrane, nuclear pores, nucleolus, DNA (chromosomes)
Nuclear membrane
In animals and plants
Has nuclear pores that regulate entrance and exit of molecules in and out of nucleus
Aka nuclear envelope
Nucleolus
In animals and plants
Where RNA is made
Dot inside nucleus
Central vacuole
In plants only Stores water and dissolved molecules Expels waste or water as necessary Increases turgor pressure to provide structure Stationary
Ribosome
In animals and plants
Proteins made here
Little dot
Attached are on the rough ER, free are just floating in the cytosol
Ribosomes are constructed in the cytoplasm
Rough endoplasmic reticulum
In animals and plants
Has attached ribosomes
Proteins enter ER after they are made
Attaches off nucleus
Smooth endoplasmic reticulum
In animals and plants
No ribosomes attached
Produces lipids like phospholipids and steroid hormones
Attaches off nucleus
Golgi apparatus
In animals and plants
Modify proteins using special enzymes
Looks like stack of pancakes
Vesicles
In animals and plants
Carry materials from ER to Golgi apparatus
Lysosomes and peroxisomes (aka digestive organelles)
Lysosomes break down waste or damaged organelles (ex. mitochondrion digested after ten days)
Peroxisomes break down H2O2 (contains catalase)
Ex. Taysachs (when lysosomes that break down lipids stop working)
Little dots
Mitochondria
In animals and plants Carries out cellular respiration "Powerhouse" of the cell Many in muscle cells Looks like oval with squiggly line
Chloroplasts
In plants only
Make sugar (food) (glucose) through photosynthesis
Pushed to the edge of the cell by the vacuole
Look like oval with rows of small circles
Cilia
Animals only
Protests
Short hair like structures that aid in cell movement
Flagella
Animals only
Protests
Whiplike structure for movement
Ex. Sperm cell
Cilia and flagella made of…
Microtubules
Cross section is 9+2 pattern (9 microtubules doublets and a center pair)
Basal body
Anchors the flagella and cilia to the cell membrane
Order of endomembrane system
Nuclear membrane, rough ER/smooth ER, Golgi body, vesicle, lysosomes, cell membrane
Eukaryotes
DNA stored in membrane-bound nucleus
Contains many membrane-bound organelles (ex. mitochondria)
DNA in multiple strands (ex. humans have 46 chromosomes)
Ex. Plants and animals
Prokaryotes
Free floating DNA in cytoplasm
Ex. bacteria
DNA found in loops
Outer layer called capsule (cell wall)
Similarities between prokaryotes and eukaryotes
Contain cell membrane, cytoplasm, DNA, ribosomes
Major differences between plant and animal cells
Plant cells have chloroplasts, animal cells don’t
Plant cells have a large permanent vacuole, animals cells have small temporary ones
Plants cells have a cell wall, animal cells don’t
Animals cells have centrioles, plant cells don’t
Animal cells and protests can have cilia/flagella, plant cells don’t
Shape of circle bacteria, stringy bacteria, soft edged-rectangle bacteria
Coccus, spirillum (spiral), bacillus (rod)
Cell theory
All living things are composed of cells and all cells come from other cells
Compound light microscopes
Uses focused beam of light and two lenses to magnify a thin specimen
Dissecting microscopes
Uses light reflected off the specimen to provide for low magnification observation
USE IN CLASS
Scanning electron microscopes
Uses reflected electrons to produce an external 3-D image and provides high resolution
Transmission electron microscopes
Passes beam of electrons through a specimen and focuses those electrons by magnetic lenses onto a screen of film
First scientist to discover and name cells
Robert Hooke
First to observe living cells (bacteria)
Antoine van Leeuwenhoek
Nucleoplasm
The substance inside the nucleus that performs a similar function to cytosol
Nucleoid
The part of a prokaryote where all or most of the genetic material is stored
Not surrounded by a nuclear membrane
Chromosomes
A thread like structure most commonly found in the nucleus that carries genetic information in the form of genes
Chromatin
A complex of DNA and proteins that forms chromosomes within the nucleus of eukaryotic cells
Bacteria
A big example of prokaryotic cells, can have rod shape (bacillus), spiral shape (spirillum), circle shape (coccus)
Capsule
The outermost layer of bacterial cells, basically a cell wall
