Cell Organelles (Unit 2)

Question 1

*Ribosomes (Structure)

Answer 1

-Made of rRNA molecules surrounded by ribosomal proteins
-small subunit has mRNA (PROGRAMMING) bonding sites where codons can be read
-large subunit has tRNA (PRODUCTION) bonding sites where amino acids are brought together and peptide bonds are formed

Question 2

*Ribosomes (Function)

Answer 2

-Synthesize proteins by translating mRNA into Amino Acid sequences
-three letter codons of mRNA pair with anticodons on tRNA

Question 3

*Golgi Apparatus (Structure)

Answer 3

-Made up of flattened, membrane-bound sacs called cisternae
-Has directionality (Cis vs Trans)
-Cis Face receives vesicles from rough ER
-Trans Faces ships vesicles out into cytosol

Question 4

*Golgi Apparatus (Function)

Answer 4

-Processes and packages proteins/lipids
- Sorts and modifies materials into vesicles so they can be transported (specifically proteins ensuring they are folded properly)
-vesicles leave through exocytosis

Question 5

*Rough Endoplasmic Reticulum (Structure)

Answer 5

-Contains ribosomes that are bound to its membrane
-Close to the nucleus

Question 6

*Rough Endoplasmic Reticulum (Function)

Answer 6

-Distributes transport vesicles (contain proteins)
-the ribosomes bounded to it secrete glycoproteins (proteins covalently bonded to Carbohydrates)
-Membrane factory for the cell

Question 7

*Smooth Endoplasmic Reticulum (Structure)

Answer 7

-DOESNT have ribosomes bound to its membrane

Question 8

*Smooth Endoplasmic Reticulum (Function)

Answer 8

-Synthesizes lipids
-Metabolizes carbohydrates
-Detoxifies drugs/poisons (prominent in liver+kidney)
-Stores calcium ions

-functions can vary with cell type (muscle cell would need to metabolize Carbohydrates for more energy)

Question 9

*Vesicles (Structure+Function)

Answer 9

-Ring of hydrophilic heads and hydrophobic tails
-Come from ER or Golgi
-Used for transporting materials

Question 10

What is exocytosis?

Answer 10

When a vesicle is exiting a membrane by fusing with it in order to release its contents

Question 11

*Lysosomes (Structure)

Answer 11

-Membranous sac containing hydrolytic enzymes

Question 12

*Lysosomes (Function)

Answer 12

-Waste management
-Hydrolyzing macromolecules within animal cells using the hydrolytic enzymes
-help to get rid of dead/damaged cells (suicide victims)

Question 13

Autophagy (Lysosomes)

Answer 13

When a cell breaks down and recycles old/damaged organic materials

Question 14

Apoptosis (…Suicide)

Answer 14

Programmed cell death occurring when a cell isn’t as efficient (examples being older cells and damaged cells) can also prevent uncontrolled cell growth+division

Question 15

PEROXIsomes (Boof Lysosome)

Answer 15

-Contains enzyme Catalase which initiates the reduction of H2O2(Hydrogen PEROXIDE) to H2O (water)
-Breaks down fatty acids to transport them to mitochondria for respiration
-protects cell from toxins and detoxify alcohol in liver through oxidation

Question 16

*Vacuole (Structure)

Answer 16

-tonoplast membrane composed of phospholipids (Hydrophilic head and Hydrophobic tail)
-tonoplast membrane allows for the organelle to maintain structure while expanding and contracting

Question 17

*Vacuole (Function)

Answer 17

-help to filter waste and manage nutrients as well as water
-Food vacuoles form through phagocytosis then digested by lysosomes
-Contractile vacuoles maintain water levels in cells (star shaped)
-Central vacuoles in plants maintain turgor pressure

Question 18

What are the endomembrane organelles (8)?

Answer 18

Nucleus, Ribosomes, Rough/Smooth ER, Golgi Complex, Lysosomes, Peroxisomes, and Vacuoles

Question 19

*Nucleus (Structure)

Answer 19

-Surrounded by a nuclear envelope
-Double Membrane with pores
-Pores regulate the entry and exit of material from the cell

Question 20

*Nucleus (Function)

Answer 20

-Controls the cells activity
-Contains nucleolus which synthesizes rRNA
-The pores of the nucleus allow for the ribosomal subunits to exit

Question 21

What are the Energy Organelles (2)?

Answer 21

Mitochondria and Chloroplasts

Question 22

*Mitochondria (Structure)

Answer 22

-Smooth outer membrane
-Folded inner membrane (cristae)
-Cristae folds increase surface area making it more efficient
-Middle is the mitochondrial matrix containing ribosomes, enzymes, and DNA

Question 23

*Mitochondria (Function)

Answer 23

-The enzymes catalyze cellular respiration and the production of ATP
-Location for krebs cycle
-apparent in cells with high metabolic activity (cells that move/contract)

Question 24

*Chloroplasts (Structure)

Answer 24

-Green due to chlorophyll
-Grana (organized stacks of thylakoids)
-Stroma is the fluid surrounding thylakoids
contains ribosomes, enzymes, and DNA

Question 25

*Chloroplasts (Function)

Answer 25

-Site of photosynthesis
-produce oxygen and glucose which provide energy for plant cells
-location for calvin cycle

Question 26

What are the different fibers in the cytoskeleton?

Answer 26

Microtubules, Microfilaments, and Intermediate Filaments

Question 27

Microtubules (M-Motility)

Answer 27

-Hollow rod structures made of protein tublin
-Serve as structural support
-Tracks for the movement of organelles interacting with motor proteins
-Main function is MOTILITY (cilia and flagella help)

Question 28

Microfilaments (M-Motility)

Answer 28

-Solid rods made of protein actin
-Maintain cell shape
-Assists in contraction and cell motility (actin causes contractions)

Question 29

Intermediate Filaments

Answer 29

-Fibrous proteins made up of subunits
-Permanent structural elements of a cell
-Anchors nucleus and organelles
-DOES NOT participate in cell motility