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