Module 1: Lesson 2

Question 1

What are the types of prokaryotes?

Answer 1

archaea and bacteria

Question 2

nucleus

Answer 2

holds genetic information

Question 3

nuclear envelope

Answer 3

separates transcription from translation

Question 4

Endoplasmic reticulum (ER)

Answer 4

secreted and membrane protein synthesis, Ca2+ storage/signaling, linked by vesicle transport to all other endomembranes

Question 5

Golgi apparatus

Answer 5

glycosylation and sorting of proteins for transport/secretion

Question 6

Lysosome

Answer 6

digestion (hydrolysis); peroxisome - oxidative metabolic functions

Question 7

Vesicles

Answer 7

transport between endomembrane organelles

Question 8

flagellum

Answer 8

for motility and sensing (eg. cilia)

Question 9

Plasma membrane (PM)

Answer 9

separates the cell from the environment

Question 10

Mitochondria

Answer 10

oxidative phosphorylation for ATP synthesis

Question 11

Chloroplast

Answer 11

photosynthesis for ATP synthesis

Question 12

Cytoskeleton

Answer 12

cell shape, cell motility, intracellular transport of organelles

Question 13

What is the problem and what are the solutions to transmitted light microscopy?

Answer 13

Problem: cells are mostly transparent
Solutions: stain cells with dyes to generate contrast, and optics that generate contrast where there is a difference in density/refractive index in cells

Question 14

What is the nuclear envelope contiguous with?

Answer 14

the endoplasmic reticulum

Question 15

Nuclear pore complex

Answer 15

regulates the movement of macromolecules (RNA and proteins) in and out of the nucleus

Question 16

Why can electrons be used for microscopy?

Answer 16

electrons have shorter wavelengths and high magnification and resolution

Question 17

Fluorescence microscopy

Answer 17

allows the detection of specific proteins or other molecules that are labeled with fluorescent molecules

Question 18

Steps of fluorescence microscopy

Answer 18

1. an electron is excited by a high-energy proton
2. relaxation causes the emission of a photon of lower energy than the one that caused the excitation

Question 19

How do you fluoresce live cells and tissues?

Answer 19

use live dyes to illuminate the specimen, and use genetically encoded fluorophores to identify the target: reporters or protein fusions

Question 20

How do you fluoresce fixed cells and tissues?

Answer 20

use dyes to illuminate the specimen, and use antibodies to identify the target: direct and indirect labeling

Question 21

What are traits of the ER?

Answer 21

it is continuous with the nuclear membrane, contains the most membrane of the cell, has tubular membranes or flattened sacs, and the inside of the ER is lumen.

Question 22

What are the traits and role of the rough ER?

Answer 22

rough ER is decorated in ribosomes on the outer surface, thus appearing “rough.” It synthesizes proteins that are exported out of the cell (secretion and exocytosis) and some membrane proteins.

Question 23

What are the roles of the smooth ER?

Answer 23

smooth ER has no role in protein synthesis and no associated ribosomes. It synthesizes lipids, sterols, and steroid hormones; detoxifies drugs and toxins; and stores calcium ions and specialized sub-domains.

Question 24

What is the role and characteristics of the Golgi complex?

Answer 24

the Golgi complex chemically modifies, sorts, and packages proteins from the rER. It consists of 3-8 flattened membrane-bound cisternae in a stack.

Question 25

What are the roles and characteristics of vesicles?

Answer 25

vesicles transport proteins and membranes to endomembrane organelles and the plasma membrane. They are small membrane-bound spherical "bubbles" that only carry proteins appropriate to their destination.

Question 26

What are lysosomes and what is their role?

Answer 26

lysosomes are small, single membrane organelles with low pH that degrade and recycle components of the cell's organelles. This includes carbohydrates, lipids, proteins, and older organelles.

Question 27

What do peroxisomes do?

Answer 27

peroxisomes are organelles that can handle hydrogen peroxide and other reactive oxygen species using special enzymes. They conduct fatty acid oxidation.

Question 28

What are lipid droplets?

Answer 28

a single phospholipid monolayer that surrounds a core of neutral lipids: sterol esters and triglycerides. They are decorated with proteins and can interact with different organelles.

Question 29

What is the cytoskeleton?

Answer 29

a system of protein filaments in the cell that undergo dynamic reorganizations. It contributes to cell motility, intracellular motility and organization, cell shape, rigidity, and structural support.

Question 30

What are the types of filaments?

Answer 30

Actin filaments, microtubules, and intermediate filaments.

Question 31

What is the difference between flagellum and cilium?

Answer 31

a flagellum is designed to move the entire cell, whereas a cilia has an equivalent structure but is shorter and more abundant.

Question 32

What is the role and characteristics of the mitochondria?

Answer 32

the mitochondria are involved with energy production and cell signaling. It is a double-membrane bound organelle made of cristae; has its own genome; and possesses the ability to move, fuse, and divide individually.

Question 33

What are chloroplasts and what is their role?

Answer 33

chloroplasts conduct ATP synthesis via photosynthesis in photosynthetic eukaryotes. This occurs in the thylakoid. Chloroplasts also have the individual ability to move, fuse, and divide; and it has its own genome.