Cell Bio Exam 2

Cristae

(plural, cristae) An infolding of the inner membrane of a mitochondrion that houses the electron transport chain and the enzyme catalyzing the synthesis of ATP. increases surface area

What is the maximum yield of ATP per glucose

38 ATP

What is the importance of adaptin, coated protein, and dynamin?

Adaptin allows the coated protein to bind with the cargo receptor. Coated protein allows the membrane to bend and form the "bubble" Dynamin separates the formed bubble from the membrane by hydrolyzation of GTP

What are the type of movement of vesicles

Anterograde: From the nucleus to outside the cell Retrograde: from the outside to the nucleus

What is the coated vesicle process?

Cargo receptor attaches to the cargo. Coat protein attaches to the cargo receptor with the help of adaptin. The protein coat allows the membrane to bend and form a bubble. Dynamin comes and separate the vesicle from the membrane and it is sent. Coated protein releases leaving the cargo receptors exposed.

What parts composes the Golgi?

Cis Golgi network (CGN): Receives or sends back vessicles coming from the ER. Trans Golgi network (TGN): Send or receives vessicles coming from the membrane

What are the types of Coated protein?

Clathrin, COPI, COPII Depending on what type of coat it has we can determine where it is going and where it came from

What is the Carb Metabolism?

Conversion of glucose into either immediate energy (ATP) or storage (glycogen). The smooth ER converts stored glycogen into glucose so it can be converted into ATP. This is triggered when ATP levels are low

Describe muscle cross-bridging

Cross-bridge formation (high energy configuration makes the myosin head to attach the actin) Pι release Power stroke (release of Pι changes confirmation and creates the movement) ADP release ATP binds Myosin (ATP causes detachment of Myosin with actin) ATP hydrolysis (returns myosin to high energy confirmation)

How can be Dynein divided into groups?

Cytoplasmic (goes to - end) Axonemal (divides into 4 more types)

In an action potential, How is increasing, decreasing, and recovery called?

Depolarization is changing from negative to a positive charge passing thru the threshold potential, Then in Repolarize until reaching an overwhelming negative charge. Later, it hyperpolarizise to the original resting potential

How does drug detox happens?

Drug are hydrophobic, enzymes in the Smooth ER add an OH group to the drugs and makes it more hydrophilic facilitating its dilution in water and ultimately excretion by peeing

Cistermere

Each individual folding or tube within the ER's

True or False: Muscle only create force by contracting

False, they can create for by relaxing as well

True or False: Ribosomes are permanently attached to the Rough ER

False. Ribosomes can freely attach and disattach

What is the structure of Kinesin?

Globular Head (Feet) Coiled α-helix Light chain region (binds to cargo)

What are the "tags" in the protein composition?

Golgi to Plasma membrane: Arg-x-Arg Golgi to ER: 8 or more hydrophobic amino acids

what is the structure of Myosin?

Head (binds to actin) Neck Tail Varies in size.

What is the structure of Dynein?

Heavy chain (feet) Intermediate chain Light chain (binds to cargo)

Phagocytosis

Ingestion of larger particles up to including whole cells.

What are the motility system?

Interaction of MT with motor protein (Dynein and Kinesin) Interaction of actin microfilaments with motor protein (Myosin which usually moves towards the - end)

What are the types of secretory pathways?

It can be unregulated (always happening) or regulated (waits for an extracellular signal to be activated)

How can you determine which motor protein would you use to move things between the ER, Golgi, and membrane

It is all relative to the MTOC which is usually in the TGN. Kinesin moves to the positive end whereas dynein moves to the minus end

Golgi complex

It is the sorting organelle. Process, modify, and ships the content from vesicles coming from the ER

Difference between Kinesins and Myosin

Kinesin works ALONE over large distance Myosin molecules moves short distance but they summate (they can work together to move things faster)

Microtubules

Largest element in cytoskeleton. Composed of α-β tubulin and 13 protofilaments. GTP

How is actin divided

Muscle-specific (α-actin) Non-muscle actin (β- and γ- actin)

Sliding-Filament Model

Neither the length of the Thin nor the Thick filament changes. They just slide More forces requires more overlap. but there is a sweet spot

Centrioles

One of two tiny structures located in the cytoplasm of animal cells near the nuclear envelope; play a role in cell division

Mitochondria

Organelle that converts the chemical energy stored in food into compounds that are more convenient for the cell to use. Have there own DNA. Different tissue have different amounts of mitochondrial depending on their activity

What Are the part of the Mitochondria?

Outer Membrane Intermembrane Space Inner membrane Cristae Matrix

What is the Vesicle budding process?

Protein Rab in the vesicle attaches to the tethering protein in the membrane. The tethering protein brings the vesicle closer to the membrane until the v-Snare in the vesicle fusion with the t-Snare of the membrane. The Snare complex interacts and brings the vesicle close enough to allow fusion of membrane

What is the most basic unit of skeletal muscle contraction?

Sacromere

How membrane synthesis occur?

Smooth ER send and receives lipids from the membrane. ER phospholipids are similar to membrane phospholipids. Lipids distribution are similar in the ER thanks to Flippase enzymes. Lipids distribution is asymmetrical in the plasma membrane due less Flippase enzyme than the ER

What are the Flippase Enzymes and name them

Switch phospholipids up and down by hydrolysis of ATP to create a symmetrical distribution. P-type ATPase ABC Transporters Scramblase

What are the functions of the Rough Endoplasmic Reticulum

System of folded membranes within a eukaryotic cell and has ribosomes bound to it, giving a rough appearance. Ribosomes attached to it synthesize and fold proteins for incorporated back into the plasma membrane, organelles of the ER system, or to export out of the cell

What are the functions of the Smooth Endoplasmic reticulum?

System where: lipids are synthesized Drug detoxification Carb metabolism Calcium levels are regulated Steroid and cholesterol synthesis Membrane synthesis The liver contains a lot of Smooth ER

Endocytosis

The cellular uptake of macromolecules and particulate substances by localized regions of the plasma membrane that surround the substance and pinch off to form an intracellular vesicle.

Lumen

The internal space in the ER membranes

Microfilaments

Thinner. Smallest monomer is G-actin that binds together to form F-actin (microfilaments) composed of 2 helical strands. Enable the cell to move or change shape when protein subunits slide past one another (contraction). ATP

Cisternae

Tubes that connect Rough ER with the Smooth ER

Lysosome

Vesicle organelle found in the cytoplasm of most cells (especially in leukocytes and liver and kidney cells) that break down all kinds of biomolecules. Synthesized on rough ER and transported to Golgi complex then packaged into vesicles.

cytoskeleton

a network of microtubules, microfilaments, and intermediate filaments that branch throughout the cytoplasm and serve a variety of mechanical and transport functions

Secretory Vesicles

contain secretions that will be discharged from the cell these vesicles will perform exocytosis (fusing with the plasma membrane to empty contents).

Inner and Outer mitochondrial membranes

encode some of the RNA proteins needed, along with proteins involved in mitochondrial function

Cotranslational Import

mRNA binds to free-floating ribosomes, then the ribosomes attach to the surface of the R.ER by a protein and the mRNA is translated into the ER.

Mitochondria matrix

the fluid that in inside the inner membrane of the mitochondria, where Krebs cycle takes place

Exocytosis

the process by which a substance is released from the cell through a vesicle that transports the substance to the cell surface and then fuses with the membrane to let the substance out.

Endosymbiont theory

the theory that mitochondria and chloroplasts originated as prokaryotic cells engulfed by an ancestral eukaryotic cell. The engulfed cell and its host cell then evolved into a single organism.