Chapter 2 - Guyton

Question 1

Two major parts of the cell.

Answer 1

nucleus and cytoplasm

Question 2

Water composes how much of the cell?

Answer 2

70-85%

Question 3

After water, the most abundant substance in most cells is?

Answer 3

protein (10-20% of cell mass)

Question 4

What is the main structural difference between structural proteins and functional proteins?

Answer 4

structural - composed mainly of long filaments; functional - tubular-globular form

Question 5

What is the significance of carbohydrate to the cell?

Answer 5

little function structurally except as part of glycoprotein but plays a major role in nutrition for the cell

Question 6

What provides “specificity” to the cell?

Answer 6

proteins

Question 7

Examples of integral proteins.

Answer 7

channels, pores, carriers, enzymes

Question 8

Examples of peripheral proteins.

Answer 8

enzymes, intracellular signal mediators

Question 9

Which type of proteins (integral or peripheral) are the majority of glycoproteins?

Answer 9

integral

Question 10

The carbohydrates on the glycocalyx have what charge?

Answer 10

negative (repel other substances)

Question 11

How does cholesterol contribute to the membranes structurally?

Answer 11

decreases fluidity and permeability while increasing flexibility and stability

Question 12

Which organelle is similar to (and contiguous with) the plasma membrane?

Answer 12

ER

Question 13

Pathway of newly formed substances to exit cell.

Answer 13

granular ER–>smooth ER–>transport vesicles–>Golgi apparatus–>secretory vesicles–>exit cell membrane

Question 14

What happens to proteins when they are “processed”?

Answer 14

crosslinked, folded, glycosylated (N-linked), cleaved

Question 15

What is synthesized in the smooth ER?

Answer 15

lipids (phospholipids and cholesterol)

Question 16

General characteristics of Golgi apparatus.

Answer 16

membrane composition similar to that of the smooth ER and plasma membrane, composed of 4 or more stacked layers of flat vesicular structures

Question 17

What occurs at the Golgi apparatus?

Answer 17

receives transport vesicles from the smooth ER, substances formed in the ER are phosporylated and glycosylated, substances are concentrated, sorted, and packaged for secretion

Question 18

What occurs during exocytosis?

Answer 18

secretory vesicles diffuse through the cytosol and fuse to the plasma membrane, lysosomes fuse with internal endocytotic vesicles

Question 19

What occurs during secretion?

Answer 19

secretory vesicles containing proteins synthesized in the RER bud from the Golgi apparatus, fuse with plasma membrane to release contents

Question 20

What are the two types of secretion?

Answer 20

constitutive (random) and stimulated (trigger)

Question 21

Lysosomes

Answer 21

vesicular organelle formed from budding Golgi, contain hydrolytic enzymes, fuse with pinocytotic or phagocytotic vesicles to form digestive vesicles

Question 22

What occurs during lysosomal storage diseases?

Answer 22

absence of one or more hydrolases (not synthesized, inactive, not properly stored and packaged), so lysosomes become engorged with undigested substrate

Question 23

Examples of lysosomal storage diseases.

Answer 23

acid lipase A deficiency, I-cell disease (non-specific), Tay-Sachs disease (HEX A)

Question 24

Peroxisomes

Answer 24

similar physically to lysosomes, two major differences are formed by self-replication and they contain oxidases, function is to oxidize substances that may be otherwise poisonous (alcohol)

Question 25

The vesicular membrane of which organelle continuously replaces the cell membrane after it forms phagocytotic or pinocytotic vesicles.

Answer 25

Golgi apparatus

Question 26

Energy from ATP is used to promote three major categories of cellular functions:

Answer 26

1) transport of substances through multiple
membranes in the cell; 2) synthesis of chemical
compounds throughout the cell; 3) mechanical
work

Question 27

The double nuclear membrane and matrix are contiguous with the ____________ ___________.

Answer 27

ER…bet you won’t forget

Question 28

What is found in the nucleoplasm?

Answer 28

chromatin (condensed DNA)

Question 29

General characteristics of the nucleolus.

Answer 29

one or more per nucleus, contains RNA and proteins, not membrane delimited, functions to form the granular subunits of ribosomes

Question 30

Receptor-mediated endocytosis

Answer 30

molecules attach to cell-surface receptors concentrated in clathrin-coated pits, receptor binding induces invagination, also ATP-dependent and involves recruitment of actin and myosin

Question 31

A maximum of how many aTP are formed per molecule of glucose degraded.

Answer 31

38

Question 32

During ATP production, glucose from carbohydrates, amino acids from protein, and fatty acids from fats are converted into what?

Answer 32

acetyl CoA

Question 33

Two locations in the body cilia.

Answer 33

inside surfaces of the human airway and fallopian tubes

Question 34

Composition of each cilium.

Answer 34

11 microtubules (9 double tubules, 2 single tubules), each cilium is an outgrowth of the basal body and is covered by an outcropping of the plasma membrane

Question 35

Ciliary movement is dependent on what?

Answer 35

ATP and also calcium and magnesium

Question 36

Ameboid locomotion

Answer 36

continual endocytosis at the “tail” and exocytosis at the leading edge of pseudopodium, attachment of pseudopodium is facilitated by receptor proteins carried by vesicles, forward movement results through interaction of actin and myosin (ATP-dependent)

Question 37

What is chemotaxis?

Answer 37

most important factor in controlling ameboid movement, either move toward the
source of a chemotactic substance (positive chemotaxis) some cells move away from the source (negative chemotaxis)

Question 38

The only means by which large macromolecules can enter the cell?

Answer 38

pinocytosis

Question 39

Only certain cells have the capability to perform this function and it involves particles rather than the macromolecules such as in pinocytosis.

Answer 39

phagocytosis