Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
82 Cards in this Set
- Front
- Back
|
What do prokaryotes and eukaryotes have in common?
|
Cytosol, Chromosome, and Ribosomes
|
|
|
What are some major differences between prokaryotes and eukaryotes?
|
Where the chromosome are stored: In prokaryotes it is stored in the nucleoid (no membrane separates this from the rest of the cell) In eukaryotes, it is stored in the nucleus, bounded by a membranous nuclear envelope
Membrane bound organelles Size |
|
|
What limits cell size?
|
Surface area to volume ratio
|
|
|
What is the name of the double membrane that separates the nucleus from the cytosol?
|
Nuclear Envelope
|
|
|
What is the difference between the nuclear lamina and the nuclear envelope?
|
The nuclear lamina is like the cytoskeleton for regular cells, while the nuclear envelope is the double membrane that separates the cell from the cytosol.
|
|
|
In the nucleus, how is DNA organized?
|
Into units called Chromosomes
|
|
|
What are chromosomes made up of?
|
Chromatin
|
|
|
What is the nucleolus?
|
This is where rRNA is synthesized from instruction in the DNA. Also, protein imported from the cytoplasm are assembled with rRNA into large and small ribosomal subunits in the nucleolus
|
|
|
How does the nucleus direct protein synthesis?
|
By synthesizing messanger RNA
|
|
|
What is the process where DNA is turned into RNA called?
|
DNA Transcription
|
|
|
What is the process where RNA is turned into Protein called
|
Translation
|
|
|
What are the primary functions of ribosomes?
|
To carry out protein synthesis
|
|
|
What are ribosomes made up of?
|
Ribosomal RNA and protein
|
|
|
What are two kinds of ribosomes and how do they differ from each other?
|
Free ribosomes are suspended in the cytosol while bound ribosomes are attached to the outside of the endoplasmic reticulum or nuclear envelope. Most of the proteins on free ribosomes function within the cytosol. Bound ribosomes generally make proteins that are destined for insertion into membranes, for packaging within certain organelles such as lysosomes.
|
|
|
What is the endoplasmic reticulum?
|
Extensive network of membranous tubules and sacs called cisternae. The ER membrane separates the internal compartment of the ER, called the ER lumen or cisternal space, from the cytosol.
|
|
|
What are some functions of the Smooth ER?
|
Metabolism, Synthesis of lipids (including oils), phospholipids, and steroids. And, it stores calcium ions.
|
|
|
What is an example of a cell rich in Smooth ER?
|
Liver, it has to detoxify drugs and such
|
|
|
What are the functions of the Rough ER?
|
Secrete certain proteins such as insulin; mostly glycoproteins. The glycoproteins are packaged in transport vesicles
A membrane factory for the cell; can also make membrane for itself |
|
|
What are glycoproteins?
|
Proteins that have carbohydrates covalently bonded to them
|
|
|
What is the function of the Golgi Apparatus?
|
Manufacturing , warehousing, sorting, and shipping center for the cell
|
|
|
What does the Golgi Apparatus consist of?
|
Flattened membranuous sacs – cisternae – looking like a stack of pita bread.
|
|
|
What is so special about the Golgi Apparatus?
|
It has a distinct polarity, with the two poles referred as the cis face and the trans face.
|
|
|
What does the cis face in the Golgi Apparatus usually do?
|
It acts the receiving department of the Golgi Apparatus; it is usually located near the ER. Vesicles that bud from the ER add its membrane and the contents of its lumen to the cis face by fusing with the membrane.
|
|
|
What does the trans face in the Golgi Apparatus usually do?
|
It is the shipping department of the Golgi Apparatus. It forms vesicles that travel to other sites
|
|
|
Where are the products of the ER modified in the Golgi?
|
From the cis region to the trans region.
|
|
|
What does Golgi Apparatus manufacture?
|
Polysaccharides
|
|
|
How does Golgi Apparatus manufacture its stuff?
|
It manufactures and refines its products in stages, with different cisternae between the cis and trans regions containing unique teams of enzymes.
|
|
|
How does the Golgi Apparatus tell where its products are going?
|
By using molecular identification tags such as phosphate groups
|
|
|
What are lysosomes?
|
It is a membrane sac of hydrolytic enzymes that an animal cell uses to digest all kinds of macromolecules.
|
|
|
What do lysosome work best in?
|
An acidic environment
|
|
|
What happens when lysosomes are not working at their optimal conditions?
|
They become mostly inactive
|
|
|
What do lysosome participate in?
|
Phagocytosis , and recycling of the cell’s own organic material called autophagy. A damaged organelle or small amount of cytosol becomes surrounded by a membrane and a lysosome fuses with this vesicle. Then the organic compounds are returned to the cytosol for reuse.
|
|
|
What are vacuoles?
|
They are diverse maintenance compartments similar to lysosome. Examples include central vacuole and food vacuoles.
|
|
|
What roles do the plant’s central vacuole play?
|
Main storage site of inorganic ions such as potassium and chloride. Disposal sites for metabolic by-products. Storage for pigments. Absorbotion of water.
|
|
|
What is the primary function of mitochondria?
|
Cellular respiration
|
|
|
What is the primary function of chloroplasts?
|
Convert solar energy to chemical energy
|
|
|
What family is the chloroplast in?
|
Plastids
|
|
|
What do chloroplasts contain?
|
Chlorophyll and other enzymes and molecules that function in the phyotosynthetic production of sugar.
|
|
|
What are the interconnected sacs called that make up the membranous system in chloroplasts?
|
Thylakoids
|
|
|
What is a stack of thylakoids called?
|
Granum
|
|
|
What is the fluid outside of the thylakoids called?
|
The Stroma
|
|
|
What do peroxisomes do?
|
Specalized metabolic compartment that contain enzymes that transfer hydrogen from various substrates to oxygen, producing hydrogen peroxide. It also contains an enzyme that converts the hydrogen peroxide to water.
|
|
|
What are glyoxysomes?
|
Initiate the conversion of fatty acids to sugar, found in fat-storing tissues of plant seeds
|
|
|
How do peroxisomes grow larger?
|
They grow larger by incorporating proteins made in the sytosol, lipids made in the ER, and lipids synthesized within the peroxisome itself
|
|
|
What is the cytoskeleton?
|
A network of fibers extending throughout the cytoplasm.
|
|
|
What are the three types of cytoskeleton?
|
Microtubules, Microfilaments, and Intermediate Filaments
|
|
|
What is the primary function of the cytoskeletion?
|
To give mechanical support to the cell and maintain its shape.
|
|
|
What is the cytoskeleton especially important for?
|
Animal cells, because they do not have cell walls
|
|
|
What does cell motility generally require?
|
Interaction of the cytoskeleton with proteins called motor proteins
|
|
|
What cytoskeleton element allows organelles to “walk”?
|
Microtubules
|
|
|
What are the functions of Microtubules?
|
Maintenance of cell shape (compression-resisting griders)
Cell Motility (as in cilia or flagella) Chromosome movements in cell division Organelle Movements |
|
|
What are the functions of microfilaments?
|
Maintenance of cell shape (tension-bearing elements)
Changes in cell shape Muscle Contraction Cytoplasmic streaming Cell Motility (pseudopodia) Cell division (cleavage furrow formation |
|
|
What are the functions of intermediate filaments?
|
Maintenance of cell shape
Anchorage of nucleus and certain other organelles Formation of nuclear lamina |
|
|
What cytoskeleton element is hollow, and what is the hollow part called?
|
Microtubules, Lumen
|
|
|
What are Microtubules made up of?
|
Hollow tubes of tubulin
|
|
|
What are microfilaments made up of?
|
2 strings of Actin twisted in a chain
|
|
|
How easily are microtubules broken down and reformed?
|
Relatively easily
|
|
|
Where do microtubules usually grow from?
|
Centrosome
|
|
|
What is the centrosome’s main function
|
Microtubule organizing center
|
|
|
What are in the centrosome of an animal cell?
|
A pair of centrioles
|
|
|
Which is longer? Cilia or Flagella?
|
Flagella
|
|
|
How do flagella and cilia differ?
|
In their beating patterns
|
|
|
What do cilia and flagella have in common?
|
A common ultrastructure. Nine doublets of microtubules each sharing part of their walls, and 2 single microtubules are in the middle.
|
|
|
What is the 9 + 2 Ultra structure?
|
Nine doublets of microtubules each sharing part of their walls, and 2 single microtubules are in the middle. It makes both flagella and cilia, also an evolutionary connection.
|
|
|
What is the name of the place where the cilium or flagellum is anchored to?
|
Basal body
|
|
|
What are responsible for the bending movements of cilia and flagella?
|
Dynein arms
|
|
|
What do Dynein arms do?
|
Cause a “walking motion”
|
|
|
What are myosin?
|
Myosin acts as a motor protein by means of projections that “walk” along the actin filaments in microfilaments.
|
|
|
What are pseudopodia?
|
Means of movement in cells such as amoeba. Pseudopodia extend and contract through the reversible assembly of actin subunits into microfilaments and of microfilaments into network that convert cytosol from sol to gel.
|
|
|
What is cytoplasmic streaming?
|
Circular flow of cytoplasm within cells.
|
|
|
What causes cytoplasmic streaming?
|
Actin-Myosin interactions and sol-gel transformations brought about by actin.
|
|
|
What cytoskeletal element is more permanent?
|
Intermediate Filaments
|
|
|
What are Intermediate Filaments responsible for?
|
Reinforcing the shape of a cell and fixing the position of certain organelles.
|
|
|
How does a eukaryotic cell compensate for low surface area-volume ratio
|
INTERNAL MEMBRANES (Endo-Membrane System) – membrane bound organelles
Partition cell into compartments Unique Lipid and Protein compositions Participate in metabolic activities o Provide Localized Environment for specific metabolic processes Sequester, or isolate, certain reactions so they don’t interfere with other metabolic processes |
|
|
What are the parts of the endomembrane system?
|
Cell Membrane
Nuclear Envelope ER Golgi Lysosomes Vacoules Vesicles |
|
|
What are the three functions of Smooth ER?
|
1. Detoxifies stuff
2. Synthesizes lipids, oils, steroids 3. Stores Calcium |
|
|
What are the two functions of the Rough ER?
|
1. "Threads" Proteins
2. Makes new Membrane |
|
|
what is myosin?
|
Myosin is the motor protein that "walk" along actin filaments, this causes the contraction of a cell
|
|
|
What is pseudopodia
|
Pseudopodia is the method of movement for amoebas, it is caused by localized contraction brough about actin and myosin.
|
|
|
What is collagen?
|
Is a glycoprotein found in the ECM that forms strong fibers outside the cell
|
|
|
What are pectins?
|
Pectins makes up the middle lamella, it is a polysaccharide
|
|
|
What does the middle lamella do?
|
It glues adjacent cells together
|
