Lecture 5.2

Question 1

What is the endomembrane system?

Answer 1

It includes plasma membrane, nuclear envelope, endoplasmic reticulum (ER), Golgi apparatus and lysosomes.

Question 2

How do substances get from compomnent to component in the endomembrane system?

Answer 2

By tiny, membrane-bound vesicles.

Question 3

What is the Endoplasmic reticulum (ER) ?

Answer 3

A network of membranes in the cytoplasm with a large surface area

Question 4

What is the rough endoplasmic reticulum (RER) ?

Answer 4

Has 80S (large) ribosomes that synthesize proteins and modifies them, folds them, and transports them to others regions.

Question 5

What is the smooth endoplasmic reticulum (SER) ?

Answer 5

Lacks ribosomes and is associated with synthesis lipids and some detoxification.

Question 6

What is the Golgi apparatus?

Answer 6

-Composed of flattened sacs (cisternae) and small vesicles.
-Receives proteins from RER and can further modify them
-Packages and sorts proteins
-And in plant cells, polysaccharides are synthesized here for the making of cell walls

Question 7

Which region of the Golgi receives vesicles from ER?

Answer 7

The cis-region

Question 8

Which region of the Golgi releases vesicles that get moved to the plasma membrane and other organelles??

Answer 8

The trans-region

Question 9

What are lysosomes?

Answer 9

They contain digestive enzymes that hydrolyze macromolecules into monomers.

Question 10

Where are primary lysosomes made?

Answer 10

In the Golgi apparatus

Question 11

How does food enter the cell?

Answer 11

By phagocytosis

Question 12

Primary lysosomes + phagosome = ?

Answer 12

Secondary lysosomes

Question 13

Which enzymes hydrolyze the food molecules?

Answer 13

Hydrolytic enzymes

Question 14

What are wastes ejected by?

Answer 14

Exocytosis

Question 15

True or False? Cells are static.

Answer 15

False. Cells are not static and are constantly changing shape.

Question 16

What are Mitochondria?

Answer 16

-double-membrane-bound organelles found in animals, plants, fungi, and some protists.
-contain one circular strand of DNA, 70S (i.e., small) ribosomes, and some enzymes.

Question 17

What is cellular respiration?

Answer 17

When the energy contained in food molecules is transformed into energy-rich ATP molecules during a metabolism.

Question 18

What are Chloroplasts?

Answer 18

-occur in plants and in photosynthetic protists (i.e., algae).
-are double-membrane-bound organelles.
-contain one circular strand of DNA, 70S (i.e., small) ribosomes, and some enzymes.

Question 19

What is photosynthesis?

Answer 19

When chlorophyll and other pigments use light energy to make ATP molecules and sugars during a metabolism.

Question 20

What is the endosymbiosis theory?

Answer 20

-the evolutionary origin of mitochondria & chloroplasts states that they originated when large prokaryotes engulfed, but did not digest, smaller ones (what are now known as mitochondria & chloroplasts).
-Mutual benefits permitted this symbiotic relationship to evolve into eukaryotic organelles of today.
-both the mitochondria & chloroplasts have their own. DNA and own 70S ribosomes and therefore make some proteins

Question 21

What is peroxisomes ?

Answer 21

Single-membrane-bound organelles involved in oxidation of fatty acids, as well as detoxification of peroxides.

Question 22

What do vacuoles contain?

Answer 22

Contain a single-membrane-bound compartment of water, dissolved substances, and digestive enzymes found in plant and algae cells.

Question 23

What is the cytoskeleton?

Answer 23

It is a cellular part within the cytoplasm of eukaryotic cells that provide shape, strength and movement.

Question 24

What are the 3 interacting types of protein fibers?

Answer 24

1) Microfilaments
2) Intermediate filaments
3) Microtubules

Question 25

What is the role of Microfilaments?

Answer 25

They strengthen cellular structures & provide movement in animal cytokinesis, in cytoplasmic streaming and in pseudopod extension.

Question 26

What is the role of Intermediate filaments?

Answer 26

They add strength to cell attachments in multicellular organisms.

Question 27

What is the role for Microtubules?

Answer 27

They lengthen & shorten to help move organelles within the cell; push & pull chromosomes during cell division.

Question 28

What is cilia?

Answer 28

Short, usually many present, move with a stiff power stroke.

Question 29

What is flagella?

Answer 29

Longer, usually one or two present, movement is snake-like.

Question 30

What is cilia & flagella made up of? What is their function?

Answer 30

Made of microtubules in a "9 + 2" pattern. Their function is to move the cell. Each one is anchored with a basal body made of microtubules in a "9 triplets" pattern.

Question 31

What are centrioles?

Answer 31

They are "9 triplets" of microtubules (structurally identical to basal bodies), involved in the formation of the mitotic spindle—to which chromosomes attach during cell division.

Question 32

What is the extracellular matrix?

Answer 32

It is anything external to the plasma membrane. The materials in this matrix provide protection, support, and attachment for cells in multicellular organisms.

Question 33

What is the cellular matrix of plants & algae?

Answer 33

A cell wall made of cellulose.

Question 34

What are the cell walls of fungi made up of?

Answer 34

Chitin.

Question 35

What do cell walls do?

Answer 35

They provide structure, and a means for withstanding high osmotic pressure in aqueous environments.

Question 36

What does the extracellular matrix consists mainly of?

Answer 36

Protein collagen and some different glycoproteins.

Question 37

Which cells have NO cell walls?

Answer 37

Animal cells and animal like cells.