AP BIOLOGY REVIEW CHAPTER 6
flagella
Locomotion organelles of some bacteria (*tail*)
Which two domains consist of prokaryotic cells
Archae and bacteria.
proteoglycan complex
Consists of hundreds of proteoglycan molecules attached non-covalently to a single long polysaccharide molecule
Desmosomes:
Fasten cells together in tight sheets; attach muscle cells to each other, sometimes muscle tears are due to the rupture of desmosomes.
Collagen
Fibers that are embedded in a web of proteoglycan complexes
What is a lysosome? What do they contain?
Lysosomes are membranous sacs of hydrolytic enzymes. -> They digest macromolecules. They contain enzymes that function in the acidic environment of the cell *One function of lysosomes is intracellular digestion of particles engulfed by phagocytosis*
The endoplasmic reticulum (ER)- amount of space it takes up
Makes up more than half the total membrane system in many eukaryotic cells
plasma membrane
Membrane enclosing cytoplasm
What is the cytoskeleton? What are its functions?
The cytoskeleton is a network is a network of fibers through the cytoplasm, that organize the structures and activities of cells. They provide mechanical support, allow motility (changes in cell location and movement of cell parts with motor proteins), and regulate.
The endomembrane system regulates _________ and performs ____________ functions in the cell
The endomembrane system regulates *protein traffic* and performs *metabolic functions* in the cell
The eukaryotic cell's genetic instructions are housed in the __________ and carried out by the ________________
The eukaryotic cell's genetic instructions are housed in the *nucleus* and carried out by the *ribosomes*
On this sketch, label the primary cell wall, secondary cell wall, middle lamella, cytosol, plasma membrane, central vacuole, and plasmodesmata.
refer to worksheet
nucleoid
region where cells contain DNA
central vacuoles in plants:
vacuoles where hydrolysis takes place. -> Develops by the joining together of smaller vacuoles, them being derived from the Golgi apparatus and endoplasmic reticulum.
Chloroplast label outer membrane, inner membrane, inner membrane space, thylakoids, granum, and stroma.
*Notice that the mitochondrion has two membrane compartments, while the chloroplast has three compartments.*
Describe the process of phagocytosis . Which human cells carry out phagocytosis?
1) Amoebas eat by engulfing wither smaller organisms or food particles. -> The food vacuole formed fuses with the lysosome, which has enzymes that breaks down this food.* -> Digestion products include simple sugars, amino acids, and other monomers, pass into the cytosol and make nutrients. 2) Human cells, such as white blood cells, help defend against bacteria.
List all the structures of the endomembrane system.
1) Endoplasmic Reticulum (smooth and rough) 2) lysosomes 3) vacuoles 4) Golgi apparatus (Mitochondria and chloroplasts are not considered part of the endomembrane system, although they are enclosed by membranes)
Evidence of embosymbiont theory
1) Mitochondria and chloroplasts- reproduce through binary fission 2) They have double membranes 3) They have circular DNA (All very similar to Bacteria).
Major functions of rough ER
1) Packaging secretory proteins into transport vesicles 2) The membrane keeps them separate from proteins that are produced by free ribosomes and will remain in the cytosol. 3) Rough ER is a membrane hotspot for the cell, growing in place by adding membrane proteins and phospholipids to its own membrane.
Three main functions of smooth ER
1) Synthesizes lipids, oils, phospholipids, and steroids 2) Help detoxify drugs and poisons 3) Helps to metabolize carbohydrates.
Describe what happens to a transport vesicle and its contents when it arrives at the Golgi apparatus.
1) The vesicle adds its membrane and the contents of it to the cis face -> from which there it is enveloped by the golgi. 2) The golgi modifies the product -> a new vesicle is formed from the trans face and leaves the golgi.
What are three functions of the cell wall
1) They protect plant cells 2) Maintain its shape 3) Prevent excessive uptake of water
Describe several functions of microtubules.
1) They shape/support cell 2) Tracks for movement 3) Guide secreting vesicles 4) separate chromosomes during cell division.
Cilia
Aid in movement, made of microtubules, short, *use "swishy movement" to move cell, many need for cell movement*
Fibronectin
Attaches the ECM to integrins embedded in the plasma membrane
Bacterial Chromosome
Circular DNA in Prokaryotes
What can pass through intercellular junctions?
Cytosol, water, and small solutes pass freely. -> Sometimes proteins and mRNA move through.
Found within the nucleus are the chromosomes. They are made of chromatin. What are the two components of chromatin?
DNA and protein
Rough ER (difference)
Has ribosomes on the surface.
Integrins
Membrane proteins with two subunits -> bind to the ECM on the outside and to associated proteins attached to microfilaments on the inside. -> This linkage can transmit signals between the cell's external environment and its interior and can result in changes in cell behavior.
There are three main types of fibers that make up the cytoskeleton. Name them.
Microtubules, microfilaments, and intermediate filaments
Flagella
aid in movement, made of microtubules, *few needed for cell movement, long, whip-like movement.*
29. What are the intercellular junctions between plant cells
Plasmodesmata -> cytoplasm is connected; *Animals cells do not have plasmodesmata.*
Tight junctions:
Prevent leakage of extracellular fluid (ex; skin).
A major difference between prokaryotic and eukaryotic cells is the location of their DNA. Describe this difference.
Prokaryotic- non membrane enclosed, no nucleus Eukaryotic- DNA in nucleus, in membrane
cell wall (prokaryotic cell)
Structure outside of plasma membrane
Lumen
The Endoplasmic Reticulum membrane that separates the internal compartment of the ER.
Golgi apparatus diagram (cis face, trans face, cistarnae)
The transport vesicles formed from the rough ER fuse with the Golgi apparatus
What is the endosymbiont theory
Theory that some organelles come from a eukaryotic cell engulfing a free-living bacteria
What is the function of ribosomes? What are their two components?
They are made of RNA and Protein Cellular Components -> carry out protein synthesis
What is the function of the chloroplasts
They are sites of photosynthesis that absorb sunlight energy and use it to create sugars from carbon dioxide and water
Explain the important role played by peroxisomes.
They contain enzymes that transfer hydrogen to water producing hydrogen peroxide. -> They use oxygen to break fatty acids into smaller molecules to be used as fuel for cellular ->They also help the liver to detoxify alcohol and other harmful compounds.
Gap junctions:
They create cytoplasmic channels for ions, sugars, amino acids, etc. to go through.
What is the function of the mitochondria?
They use oxygen to generate ATP from sugars, fats, and other food through chemical processes
Transport Vesicles
Vesicles in transit from one part of the cell to another.
When are the nucleoli visible? What are assembled here?
When the Ribosomes are divided and assembled
When do the thin chromatin fibers condense to become distinct chromosomes
When they coil up, becoming thick enough to be distinguished as separate structures.
cytoplasm
contents of the cell bound by the plasma membrane
food vacuoles
formed by phagocytosis
contractile vacuoles:
freshwater protists that pump excess water out of the cell, thus keeping a suitable concentration of ions and molecules inside the cell.
Smooth ER (difference)
lacks ribosomes