Semester Exam: organelles and functions

Question 1

Cystoplasm

Answer 1

between plasma membrane and nucleus

includes: cytosol, cytoplasmic organelles, and inclusions

Question 2

membranous organelles

Answer 2

mitochondria
perioxisomes
lysosomes
endoplasmic reticulum
golgi apparatus

Question 3

nonmembranous organelles

Answer 3

cytoskeleton
centrioles
ribosomes

Question 4

mitochondria

Answer 4

Double-membrane structure with shelflike cristae
Provide most of cell’s ATP via aerobic cellular respiration
Contain their own DNA and RNA

Question 5

ribosomes

Answer 5

contain protein and rRNA

protein synthesis

Question 6

free ribosomes synthesize

Answer 6

soluble proteins

Question 7

membrane bound ribosomes (on rough ER) synthesize

Answer 7

proteins to be incorporated into membranes or exported from the cell

Question 8

Endoplasmic reticulum

Answer 8

tubes and membranes enclosing cisternae
continuous with nuclear membrane
rough and smooth

Question 9

Rough ER

Answer 9

covered in ribosomes

makes secreted proteins, integral proteins, and phospholipids

Question 10

Smooth ER

Answer 10

tubules arranged in a looping network

Question 11

golgi apparatus

Answer 11

Stacked and flattened membranous sacs
Modifies, concentrates, and packages proteins and lipids
Secretory vesicles leave trans face of Golgi stack and move to designated parts of cell

Question 12

Lysosomes

Answer 12

membranous bags containing digestive enzymes

digest, degrade, and break down unwanted items

Question 13

endomembrane overall function

Answer 13

Produce, store, and export biological molecules

Degrade potentially harmful substances

Question 14

peroxisomes

Answer 14

Membranous sacs containing powerful oxidases and catalases
Detoxify harmful or toxic substances
Neutralize dangerous free radicals

Question 15

Cytoskeleton

Answer 15

Elaborate series of rods throughout cytosol
Microtubules
Microfilaments
Intermediate filaments

Question 16

microfilaments

Answer 16

Dynamic actin strands attached to plasma membrane

Question 17

microfilaments are involved in

Answer 17

Involved in cell motility, change in shape, endocytosis and exocytosis

Question 18

Intermediate Filaments

Answer 18

Tough, insoluble ropelike protein fibers

Resist pulling forces on the cell and attach to desmosomes

Question 19

Microtubules

Answer 19

Dynamic hollow tubes
Most radiate from centrosome
Determine overall shape of cell and distribution of organelles

Question 20

Motor Molecules

Answer 20

Protein complexes that function in motility

powered by ATP

Question 21

Centrosome

Answer 21

“Cell center” near nucleus
Generates microtubules; organizes mitotic spindle
Contains centrioles

Question 22

centrioles

Answer 22

Small tube formed by microtubules

Question 23

Cilia and flagella

Answer 23

Whiplike, motile extensions on surfaces of certain cells
Contain microtubules and motor molecules
Cilia move substances across cell surfaces
Longer flagella propel whole cells

Question 24

Microvilli

Answer 24

Fingerlike extensions of plasma membrane
Increase surface area for absorption
Core of actin filaments for stiffening

Question 25

nucleous

Answer 25

contain DNA

blueprints for cellular proteins

Question 26

nuclear envelope

Answer 26

Double-membrane barrier containing pores

Question 27

nuclear envelope:

outer layer, inner layer, pores

Answer 27

Outer layer is continuous with rough ER and bears ribosomes
Inner lining (nuclear lamina) maintains shape of nucleus
Pore complex regulates transport of large molecules into and out of nucleus

Question 28

Nucleoli

Answer 28

Dark-staining spherical bodies within nucleus

Involved in rRNA synthesis and ribosome subunit assembly