Cell Compartmentation and Metabolic Cooperation

Question 1

Compartments with an irregular shape may have equal _______ to a spherical compartment but will have a greater ______.

Answer 1

volume, surface area

Question 2

The ______ and ________ make up most of the cell while the ________ makes up the least.

Answer 2

cytosol and mitochondria

perioxosomes

Question 3

The __________ and _______ make up most of the membrane surfaces in a cell.

Answer 3

Rough ER, Inner mitochondrial membrane

Question 4

How do you obtain subcellular organelles?

Answer 4

1. Homogenize tissue and centrifuge.
2. Pellet will contain nuclei and unbroken cells while supernatant fraction contains liquid and suspended cell components. Centrifuge supernatant.

3Pellet will contain mitochondria, lysosomes and perioxosomes. Suspend pellet is SUCROSE DENSITY gradient and centrifuge. Since sucrose gradient concentration increases top to bottom, organelles will be ordered : Lysosomes, Mitochondria and then perioxosomes.

4. Centrifuge supernatant from step 3. Pellet will contain fragmented RER and SER that has released to form vesicles. Supernatant will contain cytosol and free ribosomes.

Question 5

List the order organelles can be released during subcellular organelle extraction.

Answer 5

1. Pellet: Nuclei, unbroken cell
2. Supernatant
3. Pellet has lysosomes, mitochondria and perixosomes organized top to bottom by sucrose density gradients
4. Supernatant
5. Pellet contains RER and SER that has reformed to form vesicles
6. Supernatant has cytosol and free ribosomes

Question 6

The outer nuclear membrane and inner nuclear membrane are joined at ___________.

Answer 6

nuclear pore complexes

Question 7

The nucleolus is responsible for ______.

Answer 7

Synthesis of rRNA

Question 8

The nucleoplasm is responsible for ________ and _____.

Answer 8

DNA replication, synthesis of tRNA and mRNA

Question 9

_______ and _____ do NOT have nuclei.

Answer 9

RBC and platlets

Question 10

The RER is continuous with ribosome bound _________ of the ________.

Answer 10

outer membrane, nucleus

Question 11

The main marker of the ER is __________ ,a _______.

Answer 11

Glucose-6-phosphatase, membrane bound enzyme

Question 12

Functions of the SER

Answer 12

Synthesis of lipids and steroid hormones

Detox of drugs and poisons

Oxidation of xenobiotics

Question 13

Functions of the RER

Answer 13

Protein synthesis of secretory proteins, peptide neurotransmitters

N-linked glycosylation

Question 14

_________ and ___________ are rich in SER.

_____ in sperm contain lots of SER to synthesize and secrete lipid-containing hormones such as ______

Answer 14

Liver hepatocytes and hormone-producing cells of adrenal cortex

Leydig cells, testosterone

Question 15

Mitochondria have an _________ containing _________. The ______________ membrane is ___________ making it permeable to only _________. It has all complexes of the _____, ____and ________.

The highly curved _______ increases _____.

Answer 15

outer membrane , porins making it permeable to molecules 10kD or less

inner membrane, tightly packed, small molecules

ETC, ATP synthetase complex, transport protines

cristae, surface area

Question 16

ATP can be synthesized via ____________ which involves several proteins in the in _________.

Answer 16

oxidative phosphorylation , inner mitochondrial membrane

Question 17

_________ have few mitochondria while ________, _______, _______ cells contain lots as well as ______.

Answer 17

Mature RBC

Liver, Cardiac, Skeletal, Ovum

Question 18

______ have fewer cristae structures because they do not use a lot of ATP.

Answer 18

Pancreas Cells

Question 19

What lipid makes up 20% of the inner mitochondrial membrane. In mammals, this resides exclusively in ________.

Answer 19

Cardiolipin

Innermitochondrial membrane

Question 20

What are the 3 main functions of mitochondria?

Answer 20

Generate chemical energy as ATP

Regulate cell apoptosis

Beta-oxidation

Question 21

What can reduce mitochondrial efficiency

Answer 21

Production of ROS can cause mitochondrial DNA,lipid and protein damage.

Question 22

Lysosomes _________. They contain _____ with an optimal. low pH value.

Answer 22

degrade extracellular and intracellular materials.

Hydrolases

Question 23

Endosomes ___________ . Lysosomes will _______ with endosomes to held degrade material within.

Answer 23

perform endocytosis

combine

Question 24

The 3 functions of the golgi body are to _________, _______ and ________.

Answer 24

O-linked glycosylation

Protein sortin

Synthesis of glycolipids and sphingomyelins.

Question 25

The golgi can also add ________ to ________ for trafficking to _____.

Answer 25

Mannose-6-phosphate, proteins

lysosomes

Question 26

___________ also known as I cell disease is a ________,_____ and _______ caused by a defect in ______________.

Patients cannot add _________ to ______ to make _____________ in the ______.Thus __________ are secreted extracellularly rather than being transported to _______. Patients are unable to break down _________.

Symptoms include :

Answer 26

Mucolipidosis II (ML II)

Genetic,Metabolic, Lysosomal Storage Diseases

N-acetylglucosaminyl-1-phosphotransferase

phosphate to mannose to make mannose-6-phosphate

glycoproteins, lysosomes

mucolipids ( sphingolipid with sialic acid/neuraminic acid)

Coarse facial features, restricted joint movement, hand deformities, developmental delay, heart valve abnormalities, weak muscle tone, abnormality of NS.

Fatal in childhood (often)

Question 27

Describe the 3 vesicular trafficking proteins of proteins and lipids (_______, _______).

Answer 27

Glycolipids and sphigomyelins

1. COP1 : Golgi to golgi; cis-golgi to ER
2. COPII: ER to cis-Golgi
3. Clathrin: trans Golgi to lysosomes, plasma membrane to endosomes

Question 28

The cytoskeleton is a organelle in _______- cells that determines _____ and enables cells to _____. It contains __________ made of ________. (x3)

Answer 28

eukaryotic

cell shape, transport vesicles and to migrate

Microfilaments: Actin (7nm)
IF: Proteins (10nm)
Microtubules Tubulin (24 nm)