Ch 6 review /test questions

Which structure is not part of the endomembrane system? a.chloroplast b. nuclear envelope c. ER d. Golgi apparatus e.plasma membrane

A

Which structure-function pair is mismatched? a)microtubule; muscle contraction b)nucleolus; production of ribosomal subunits c) lysosomes; intracellular digestion d) ribosomes; protein synthesis

A

Cyanide binds to at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found within the Cyanide binds to at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found within the A. ribosomes. B.mitochondria. C.lysosomes. D.endoplasmic reticulum. E.peroxisomes

B

What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell? A. Golgi - ER - lysosome B. ER - Golgi -vesicles that fuse with plasma membrane C.ER- Golgi - nucleus D.ER - lysosomes - vesicles that fuse with plasma membrane E. nucleus- ER - Golgi

B

Describe two common charactersitics of chloroplasts and mitochondria. Consider both function and membrane structure

Both are involved in energy transformation. (Mitochondria in cell respiration & chloroplasts in photosynthesis.) Both have multiple membranes that separate their interior into compartments. In both the innermost membranes, cristae (infoldings of inner membrane-mitochondira. & thykaloid in chloroplasts) have large surface areas with embedded enzymes that carry out their main functions

Describe shared features of microtubule-based motion of flagella and microfilament-based muscle contraction.

Both systems of movement involve long filaments that are moved in relation to each other by motor proteins that grip, release, and grip again adjacent polymers.

Structure & function of mitochondria.

Bounded by double-membrane. Inner membrane has foldings (cristae). function: cellular respiration and most ATP is generated.

Which of the following is present in a prokaryotic cell? Which of the following is present in a prokaryotic cell? A. ER B.nuclear envelope C.ribosome D.chloroplast E.mitochondrion

C

Which cell would be best for studying lysosomes? A. Muscle cell B. Nerve cell C. Phagocytic white blood cell D.Bacterial cell

D

Which structure is common to plant and animal cells? A. wall made of cellulose B.chloroplast C.centriole D. mitochondrion E.central vacuole

D

Structure & function of endoplasmic reticulum.

Extensive network of membrane-bound tubules & sacs. Membrane separates lumen from cytosol. Continuous with nuclear envelope. FUNCTION: 1) Smoother Er- synthesis of lipids, metabolism of carbohydrates, calcium storage, detoxification. 2) Rough ER- Aids in synthesis of secretory and other proteins from bound ribosome. Adds carbohydrates to glycoproteins. Produces new membrane

Structure & function of vacuole

Large membrane bounded vesicles in plants. Function: Digestion, storage, waste disposal, water balance, cell growth, and protection.

Structure & function of lysosome.

Membrabous sac of hydrolytic enzymes (in animal cells). function: breakdwn of ingested substances, cell macromolecules, & damaged oganelles for recycling.

Describe the molecular composition of nucleoli and explain their function.

Nucleoli consist of DNA & ribosomal RNA (rRNA) made according to its instructions,a s well as proteins imported from the cytoplasm. Together the rRNA & proteins are assembled into large & small ribosomal subunits.

What role do ribosomes play in carrying out genetic instructions?

Ribosomes in the cytoplasm translate the genetic message, carried from the DNA in the nucleus bt mRNA, into a polypeptide chain.

Describe the strucutural and functional difference between the smooth ER and rough E

Smooth ER has no ribsomes present, rough ER has bound ribosomes. Both make phospholipids,but membrane proteins and secretory proteins are all produced on the rough ER. Smooth Er also functions inn detoxification, carbohydrate metabolism, & storage of calcium ions.

Structure & function of peroxisome.

Specialized metabolic compartment bounded by a single membrane. Function: contains enzymes that transfer hydrogen to water, producing hydrogen peroxide as a by-product, which is converted to water by other enzymes in the peroxisome.

structure & function of Golgi apparatus

Stacks of flattened membranous sacs; has polarity (sic & trans faces). Function: Modification of proteins, carbohydrates on proteins, and phospholipids. Synthesis of many pollysaccharides. Sorting of golgi products, which are then released in vesicles.

Structure & Function of the nucleus

Surrounded by nuclear envelope (double membraned). Perforated be nuclear pores. Function: Houses chromosomes, made of chromatin (DNA, genetic material, and proteins), contains nucleoli.

In what ways are the cells of plants and animals structurally different from single-celled eukaryotes?

The most obvious difference is the presence of direct cytoplasmic connections between cells of multicellular plants (plasmodesmata) and animal (gap junctions). These connections result in the cytoplasm being continuous between adjacent cells.

Describe how transport vesicles intergrate the endomembrane system.

Transport vesicles move membranes and substances they enclose between other components of the endomembrane system.

Structure & function of ribosomes.

Two subunits made of rRNA and proteins; can be free in cytosol or bound to rough ER. Function: protein synthesis.