Cell Biology C

[Uber]

Why glycine often the most evolutionary conserved amino acid? (One hypothesis)

Answer? (Click to Show Hidden Text)

It's because glycine is the simplest possible amino acid, having just an atom of hydrogen as its side chain?

It was part of what I was looking for.

Elaborated (Click to Show Hidden Text)

Because glycine only has an atom of hydrogen for the side chain, it can form many more unusual bonds angles that other amino acids cannot (See its Ramachandran plot). Because of its uniqueness, any other amino acids mutated in will likely destabilize the protein, and not be selected.

Your turn!

Edit: This is kinda more protein than cell bio

[finagle29]

How does receptor-mediated endocytosis differ from pinocytosis?

[Uber]

How does receptor-mediated endocytosis differ from pinocytosis?

Answer? (Click to Show Hidden Text)

Receptor-mediated endocytosis is triggered by ligands binding to a receptor, triggering endocytosis of both the ligand and receptor. Pinocytosis occurs constantly (not sure about how it triggers) and are nonspecific.

[finagle29]

How does receptor-mediated endocytosis differ from pinocytosis?

Answer? (Click to Show Hidden Text)

Receptor-mediated endocytosis is triggered by ligands binding to a receptor, triggering endocytosis of both the ligand and receptor. Pinocytosis occurs constantly (not sure about how it triggers) and are nonspecific.

Correct! Your turn.

[Uber]

1. Three types of vesicles. What are each used for?
2. Two types of SNARE proteins. Describe their function in vesicle trafficking. What does SNARE stand for?
3. What is hemifusion?
4. Why don't cells get smaller with continuous endocytosis? What is the name of this system?

[asthedeer]

1. Three types of vesicles. What are each used for?
2. Two types of SNARE proteins. Describe their function in vesicle trafficking. What does SNARE stand for?
3. What is hemifusion?
4. Why don't cells get smaller with continuous endocytosis? What is the name of this system?

Hmmph. So I had answered this, but then I took such a long time that SciOly.org logged me out....but I'm back to answer these.

1. Three types of vesicles are vacuoles, which are used to regulate pressure and water levels in a cell (maintain homeostasis), lysosomes, which contain enzymes to digest stuff, and transport vesicles, which transport stuff.

2. Two types of SNARE proteins are Vesicle or v-SNAREs and Target or t-SNAREs. SNAREs identify the vesicle’s cargo and complementary SNAREs act to cause the fusion of the vesicle and target membrane during vesicle docking.SNARE stands for Soluble NSF Attachment Protein Receptor.

3. Hemifusion is partial fusion during lipid bilayer fusion.

4. Cells don't get smaller with continuous endocytosis (exocytosis?), because (I'm really just guessing at this point, idk) they also perform exocytosis at the same time....? No idea, haha!

[Uber]

Hmmph. So I had answered this, but then I took such a long time that SciOly.org logged me out....but I'm back to answer these.

1. Three types of vesicles are vacuoles, which are used to regulate pressure and water levels in a cell (maintain homeostasis), lysosomes, which contain enzymes to digest stuff, and transport vesicles, which transport stuff.

2. Two types of SNARE proteins are Vesicle or v-SNAREs and Target or t-SNAREs. SNAREs identify the vesicle’s cargo and complementary SNAREs act to cause the fusion of the vesicle and target membrane during vesicle docking.SNARE stands for Soluble NSF Attachment Protein Receptor.

3. Hemifusion is partial fusion during lipid bilayer fusion.

4. Cells don't get smaller with continuous endocytosis (exocytosis?), because (I'm really just guessing at this point, idk) they also perform exocytosis at the same time....? No idea, haha!

Remember to use hide.
4. The idea is right, but the name is endocytotic-exocytotic cycle (not that it matters)
The rest is good! Good job!

[asthedeer]

Hmmph. So I had answered this, but then I took such a long time that SciOly.org logged me out....but I'm back to answer these.

1. Three types of vesicles are vacuoles, which are used to regulate pressure and water levels in a cell (maintain homeostasis), lysosomes, which contain enzymes to digest stuff, and transport vesicles, which transport stuff.

2. Two types of SNARE proteins are Vesicle or v-SNAREs and Target or t-SNAREs. SNAREs identify the vesicle’s cargo and complementary SNAREs act to cause the fusion of the vesicle and target membrane during vesicle docking.SNARE stands for Soluble NSF Attachment Protein Receptor.

3. Hemifusion is partial fusion during lipid bilayer fusion.

4. Cells don't get smaller with continuous endocytosis (exocytosis?), because (I'm really just guessing at this point, idk) they also perform exocytosis at the same time....? No idea, haha!

Remember to use hide.
4. The idea is right, but the name is endocytotic-exocytotic cycle (not that it matters)
The rest is good! Good job!

I'm not sure how to do hide...I tried...but it didn't work.

My turn-

Define and give the functions of at least 5 of these organelles-

a. Nucleus
b. Mitochondria
c. Chloroplast
d. Golgi apparatus
e. Rough ER
f. Smooth ER
g. Ribosome
h. Lysosome
i. Cell membrane
j. Vacuoles, any type

[Unome]

Hmmph. So I had answered this, but then I took such a long time that SciOly.org logged me out....but I'm back to answer these.

1. Three types of vesicles are vacuoles, which are used to regulate pressure and water levels in a cell (maintain homeostasis), lysosomes, which contain enzymes to digest stuff, and transport vesicles, which transport stuff.

2. Two types of SNARE proteins are Vesicle or v-SNAREs and Target or t-SNAREs. SNAREs identify the vesicle’s cargo and complementary SNAREs act to cause the fusion of the vesicle and target membrane during vesicle docking.SNARE stands for Soluble NSF Attachment Protein Receptor.

3. Hemifusion is partial fusion during lipid bilayer fusion.

4. Cells don't get smaller with continuous endocytosis (exocytosis?), because (I'm really just guessing at this point, idk) they also perform exocytosis at the same time....? No idea, haha!

Remember to use hide.
4. The idea is right, but the name is endocytotic-exocytotic cycle (not that it matters)
The rest is good! Good job!

I'm not sure how to do hide...I tried...but it didn't work.

My turn-

Define and give the functions of at least 5 of these organelles-

a. Nucleus
b. Mitochondria
c. Chloroplast
d. Golgi apparatus
e. Rough ER
f. Smooth ER
g. Ribosome
h. Lysosome
i. Cell membrane
j. Vacuoles, any type

Look at bernard's signature

You need a | inside the tag; it separates the hidden text (right side of the pipe) and the shown text (left side)

[finagle29]

Not sure what you meant by "define" but here goes (Click to Show Hidden Text)

b. Mitochondria - the powerhouse of the cell, the mitochondria is where most of the ATP synthesis occurs in aerobic cells.  Citric acid cycle occurs here along with oxidative phosphorylation to harness the chemical energy stored in pyruvate. 
d. Golgi apparatus - looks like a stack of flattened pancakes, the Golgi apparatus modifies and packages proteins before they are to be secreted or stored in a membrane.  Transport vesicles enter on the cis side of the Golgi from the RER, are modified as they pass through the medial Golgi and exit in a vesicle to be secreted or become a lysosome.
e. Rough ER - a high folded membrane studded with ribosomes, the RER is the site of the synthesis of proteins that are to be secreted
g. Ribosome - small organelle in all cells that assembles polypeptide sequences from mRNA and amino acids
j. Vacuoles, any type - central vacuole is a large vacuole full of water and nutrients that occupies the majority of the volume inside a plant cell, contractile vacuoles collect water in freshwater protists and contract to expel the excess water from the cell, acting as a bilge pump