Module 1/ Organelles, Nucleus, ER, Golgi, Lysosomes, Peroxisomes, Vacuole

Question 1

Nucleus

Answer 1

Organelles in eukaryotic cell containing genetic material (chromosomes). Some genes on mitochondria and chloroplasts.

The nuclear envelope is a double membrane (two bilayers of lipids) supported by a nuclear lamina (network filaments proteins)

Question 2

Chromatin

Answer 2

Is a complex of DNA + histoine proteins making up chromosomes in eukaryotes. Can condense (coil) during cell division.

Question 3

Human chromosomes

Answer 3

46 chromosomes (2n=46)
-22 pairs of autosomal chromosomes
-1 pair of sexual chromosomes (XY)

gametes have a single set of each

Question 4

Nucleolus

Answer 4

Specialized structure in the nucleus, consisting of chromosomal regions containing ribosomal RNA (rRNA) genes along with ribosomal proteins imported from the cytoplasm to form ribosomes.

Ribosomes are free in the cytosol or bound to the outer layer of the endoplasmic reticulum depending on the destination of the proteins synthesized.

Question 5

Endoplasmic Reticulum

Answer 5

Membrane network, continuous with the outer nuclear membrane.

Question 6

Rough ER

Answer 6

Contain ribosomes, they synthesis proteins that are secreted by the cell (ex: glycoproteins) or sent to other parts of the cell

Question 7

Membrane proteins

Answer 7

They are inserted directly into the ER membrane before they are also sent to various parts of the cell

Question 8

Smooth ER

Answer 8

Ribosome-free and contains many enzymes responsible for many metabolisms.

-Synthesis of proteins
-Detoxification of lipids, phospholipids, steroids
-Calcium storage

Question 9

Golgi Apparatus

Answer 9

The Golgi apparatus is a trafficking center: manufactures, receives, sorts, modifies, ships many molecules. Vesicles arrive from the ER, fuse with the GA membranes and leave the GA(cis-to-trans direction)

Question 10

PTM’s

Answer 10

88% of PTM’s are either phosphorylation (addition of phosphate), glycosylation (addition of carbohydrate) or acetylation (addition of an acetyl).

Question 11

Lysosomes

Answer 11

Lysosomes are digestive organelles that contains hydrolytic enzymes (digestion of macromolecules). pH level= 5.0 and 4.5

Question 12

Peroxisomes

Answer 12

Is a single-membrane oxidative organelles that contain enzymes (often in the form of crystals) that remove hydrogen atoms from substrates and transfer them to oxygen (O2). It produces hydrogen peroxide.

-Their role is to break fatty acids into smaller molecules for cellular respiration.

-Detoxify harmful compounds

Question 13

Vacuole

Answer 13

Large vesicle derived from the ER and GA that are semi-permeable. (highly-selective)

Their role
-storage of molecules
-contains pigments, ions, water, and waste products

Question 14

Nuclear pore

Answer 14

Nuclear pore complexes regulates the entry and exit of nucleic acids and proteins.