Test 3 - Lecture 24

Question 1

Lysosomes:

Answer 1

membrane - enclosed organelles that contain enzymes to break down all types of biological polymers.

Question 2

Lysosomes are the ______ system of the cell

Answer 2

diestive

Question 3

Lysosomes can vary in _____ and _____ depending on the materials that have been taken up for ______.

Answer 3

size
shape
digestion

Question 4

Lysosomes contain about ___different degradative enzymes

Answer 4

60

Question 5

Mutations n genes that encode these enzymes result in _____ _____ ______ - undergraded material accumulated in the lysosomes of affected individuals

Answer 5

lysosomal
storage
diseases

Question 6

______ ______ : The enzyme deficiency in ______ ______ prevents the hydrolysis of __________ to glucose and ceramide.

Answer 6

Gaucher Disease
Gaucher Disease
glucosylceramide

Question 7

Gaucher Disease:
In the most common form of the disease, _____ are the only cells affected. Their function is to eliminate aged and damaged cells by _________.

Answer 7

macrophages

phagocytosis

Question 8

Most lysosomal enzymes are ____ _______ - active at pH 5 in lysosomes, but not in the _______ (pH 7.2)

Answer 8

acid hydrolases

cytoplasm

Question 9

This prevents uncontrolled digestion of cell contents if the _______ ________ breaks down.

Answer 9

lysosome membrane

Question 10

To maintain the acidic pH, a ______ ______ in the lysosomal membrane actively transports protons into the lysosome.

Answer 10

proton pump

Question 11

Lysosomes digest material taken up from outside the cell by _______

Answer 11

endocytosis

Question 12

Lysosomes are formed when transport vesicles from the ____ - _____ network fuse with a late endosome.

Answer 12

trans - Golgi

Question 13

Three types of endosomes: ______, _______, and ______ endosomes

Answer 13

early
recycling
late

Question 14

Early endosomes receive _______ vesicles directly from the plasma memebrane

Answer 14

endocytic

Question 15

They separate molecules targeted for ______ from those destines for _______ in lysosomes.

Answer 15

reclycling

degradation

Question 16

The molecules to be recycled are passed to ______ endosomes and back to the plasma membrane

Answer 16

recycling

Question 17

Molecules destined for degradation are transported to mulitvesicular bodies ad then to ______ endosomes

Answer 17

late

Question 18

Transport vesicles carrying ____ ______ from the trans - Golgi network then fuse with late endosomes, which mature into _______

Answer 18

acid hydrolases

lysosomes

Question 19

____ _______ are targeted to late endosomes by mannose - 6 - phosphate residues, whic are recognozed by mannose - 6 - phosphate receptors in the trans Golgi network ans packaged into _____ - _____ vesicles

Answer 19

Acid hydrolases

clathrin - coated

Question 20

Phagocytosis:

Answer 20

specialized cells such as macrophages take up and degrade large particles, including bacteria, cell debris , and aged cells.

Question 21

The particles are taken up in phagocytic vacuoles (__________), which fuse with lysosomes to become __________

Answer 21

phagosomes

phagolysosomes

Question 22

Autophagy:

Answer 22

turnover of the cell’s own componenets

Question 23

Autophagy -

Important in embryonic development and programmed cell _____

Answer 23

death

Question 24

A small area of cytoplasm or organelle is enclosed in a vesicle (_________) which fuses with a lysosome, and its contents are digested

Answer 24

autophagosome

Question 25

Autophagy leads to continuous ________ of cellular constituents

Answer 25

turnover

Question 26

Autophagy - It can also be regulated during development in response to ______ It nutrient _______ occurs, autophagy degrades nonessential macromolecules so their components can be ______ Autophagy also plays an important role in programmed cell death

Answer 26

stress starvation reutilized

Question 27

1. The generation of ________ energy is a major activity of all cells

Answer 27

metabolic

Question 28

2. _______ generate energy from breakdown of lipids and carbohydrates

Answer 28

Mitochondria

Question 29

3. _______ use sunlight energy to generate ATP and reducing power to synthesize carbohydrates form CO2 and H2O

Answer 29

Choloropasts

Question 30

4. _______ contain enzymes involved in a variety of metabollic

Answer 30

Peroxisomes

Question 31

Mitochondria, Chloroplasts and Peroxisomes - | Proteins are synthesized on _____ ribosomes and imported to these organelles as completed ________

Answer 31

free | polypeptides

Question 32

1. Mitochondria and chloroplasts also have their own _______, including some genes that are transcribed and translated within the organelle

Answer 32

genomes

Question 33

2. Mitochondria are surrounded by a _______ - ________ system

Answer 33

double - membrane

Question 34

Mitochondria - | Inner and outer membranes are separated by an _________ space

Answer 34

intermembrane

Question 35

Mitochondria - | The inner membrane has numerous folds (______), which extend into the interior (______)

Answer 35

cristae | matrix

Question 36

Mitochondria - | 1. The matrix : contains _______ system and ______ for oxidative metabolism

Answer 36

genetic | enzymes

Question 37

Mitochondria - 2. _______ (form glycolysis) is transported to mitochondria, (1) complete oxidation to CO2; (2) yields the bulk of energy (ATP)

Answer 37

Pyruvate

Question 38

Mitochondria - 3. The enzymes of the citric acid cycle are in the mitochondrial _____ Glycolysis occurs in the cytosol: pyruvate is transported into mitochondria, where its complete _______ to CO2 yields the bulk of usable energy (ATP) obtained from _______ ________

Answer 38

matrix oxidation glucose metabolism

Question 39

Glycolysis takes place in the ______

Answer 39

cytosol

Question 40

In eukaryotic cells, pyruvate is then transported into ________, where it is completely oxidized

Answer 40

mitochondria

Question 41

Pyruvate undergoes oxidative decarboxylation in the presense of ______ _ (____ - __), forming ______ ____; generation of _____

Answer 41

coenzyme A (CoA - SH) acetyl CoA 2NADH

Question 42

Acetyl CoA enter the ____ _____ cycle (_____ cycle)

Answer 42

citric acid | Krebs

Question 43

The 2 - carbon acetyl group combines with oxaloacetate ( ___ carbons) to yield ____ ( 6 carbons)

Answer 43

4 | citrate

Question 44

In the remaining reactions, 2 carbons of citrate are completely ______ to CO2 and oxaloacetate is _______

Answer 44

oxidized | regenerated

Question 45

2 carbons of citrate:

Answer 45

``` 2 CO2 1 oxaloacetate 1 GTP 3 NADH and 1 FADH2 ```

Question 46

Oxidation of glucose:

Answer 46

6 molecules of CO2, 4 ATP, 10 NADH, 2 FADH2

Question 47

Total ATP yields from oxidation of glucose: 38 ( in some cells 36) Glycolysis: _ ____ + 2 NADH Citric acid cycle: 2 ATP + _ _____ + 2 FADH2 Oxdative phophorylation: each NADH yields _ ATP, each _____ yields 2 ATP Total: 2 ATP + 2 ATP + 10*3 (NADH) + 2*2 (FADH2) = 38

Answer 47

2 ATP 8 NADH 3 FADH2

Question 48

1. _______ _ receives _______ from the citric acid cycle intermediate succinate

Answer 48

Complex II | electrons

Question 49

2. These electrons are transferred to FADH2, rather than NADH, and then to _______ _

Answer 49

coenzyme Q

Question 50

True/False: | The first step of transfer does not yield free energy

Answer 50

True

Question 51

Mitochondria - | 1. The enzymes of the ____ _____ _____ are in the mitochondrial matrix

Answer 51

citric acid cycle

Question 52

Mitochondria - 2. Most of the energy is produced by _________ _________, takes place in the ______ mitochondrial membrane

Answer 52

oxidative phosphorylation | inner

Question 53

Mitochondria - 3. _____ - energy electrons form NADH and FADH2 are transferred through a series of carries in the _______ to molecular oxygen

Answer 53

High | membrane

Question 54

Mitochondria - | 4. The energy derived from this is converted to potential energy stored in a ______ ______, which drives ATP synthesis

Answer 54

proton gradient

Question 55

Mitochondria - 1. The inner membrane The principal site of ____ _______ Surface area is increased by _______ into cristae Contains a high percentage of _______ involved in oxidative metabolism and transport ________ to most ions and small molecules - this helps maintain the proton gradient

Answer 55

ATP generation folding proteins impermrable

Question 56

Mitochondria - 2. The outer mitochondrial membrane ______ permeable to ______ molecules Contains _______, which form channels that allow the free diffusion of small molecules Composition of the intermembrane space is similar to the ______

Answer 56

Highly small porins cytosol

Question 57

Mitochondria - | 3. Position; often near locations of ____ - _____ use, such as synapses in nerve cells

Answer 57

high - energy

Question 58

In most mitochondria form an ___________ network, and are constantly ______ and _______ to remodel this network, and modify mitochondrial ________ and function

Answer 58

interconnected fusing dividing morphology

Question 59

Mitochondrial genomes usually ______ DNA molecules, present in ________ copies encode only a few proteins that are essential for ________ __________ encode all the _____ and most of the _____ needed for translating the protein - coding sequences

Answer 59

``` circular multiple oxidative phosphorylation rRNAs tRNAs ```

Question 60

The human mitochondrial genome encodes __ proteins involved in _______ _______ and oxidative phosphorylation The sequences are designed as _________ ________ I, II, III, IV or V Plus ___ and 12S rRNAs; and 22 _____, which are required for translation of the proteins

Answer 60

``` 13 electron transport respiratory complexes 16S tRNAs ```

Question 61

True/False: | The mitochondrial genetic code is the same form the universal code

Answer 61

False - | It is different

Question 62

U in the tRNA anticodon can pair with any of the four bases in the ____ codon position of mRAN; thus four codons are recognized by a _____ ______

Answer 62

third | single tRNA

Question 63

Some codons specify different amino acids in ________ than in the universal code

Answer 63

mitochondrua