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Cell Structure

Biological Membranes

I need a clear and detailed explanation on biological membrane characteristics such as biochemical properties (eg. composition, alignment, special features, etc.), biological transport routes and mechanisms of transport, and the properties of integral and peripheral proteins.

GAP JUNCTIONS for Multicellular Organisms

As multicellular organisms decelop from embryo to adults, gap junctions are made and broken in specific patterns, involving specific tissues. This suggests that these junctions play an important role in signalling between cells during embryonic development. A) With the understanding of Gap junctions, speculate on what sorts

Cell to Cell Contact Computing

Electrical coupling requires Ion flow. FOr cardiac muscle cells to contract in unision, there must be electrical coupling between cells. What type of cell to cell contact is most likley responsible for this coupling? What cell to cell junctions connect epithelial cells to a basment membrane

Signal pathway comparison

Consider the signalling pathway that proceeds through three protein kinases that are sequentially activated by phosphorylation. IN one case the kinases are held in a signalling complex by a scaffolding protein; in the other, the kinases are freely diffusing (see figure attached). Discuss the properties of these two types of orga

Water solubility of secondary messengers

Is it true that all small intracellular mediators (second messengers) are water-soluble and pass freely through the cytosol? Why? I know this is true, but why is it true?

Isolate Peroxisomes

How do you isolate peroxisomes from cells. (I don't need a complicated technical answer, but more of a general idea).

Transport vesicles, secretory vesicles, and endocytotic vesicles

Whats the difference between transport vesicles, secretory vesicles, and endocytotic vesicles? I know that Transport vesicles move molecules between locations inside the cell. For example they move proteins from the ER to the Golgi, from there to the outer membrane, where they are secreted

Phospholipid Bilayer Components

What are the three chief components of eukaryotic cell membranes? Where does each originate? What organelle synthesizes new membrane? What accounts for the stability of phospholipid bilayers in acqueos systems? Would the three components be the integral membrane protein, cholesterol, and lipid? Is the ER the organelle th

Radioactive Ribosmal Subunits

You prepare radioactivley labelled ribosomal subunits and you microinject them into cells that you are culturing in the laboratory. At different times after you inject the subunits, you take a small amount of cells and analyze them by electron microscopy. You find very soon after injection, the labelled subunits are assembled in

Permeability

What types of chemical can generally pass through phospholipid portions of the cell membrane and why? What types are generally prevented from passing through and why? I would guess hydrophillic chemicals can pass through.

Coat Proteins

The image shows the inner face of a cell membrane with numerous budding structures, each one surrounded by coat proteins. What process is going on, and what is the role of the coat proteins? See the attached file.

the location of ribosomes

You prepare radioactivley labelled ribosomal subunits and you microinject them into cells that you are culturing in the laboratory. At different times after you inject the subunits, you take a small amount of cells and analyze them by electron microscopy. You find very soon after injection, the labelled subunits are assembled in

COPII Assembly

I am currently studying the intracellular distribution of a particular protein. The protein is normally Golgi-resident. What would happen to this distribution if I treated the cell with an inhibitor of COPII assembly? I would think that if the COPII vesicles are inhibited the ER would be unable to export cargo to the golgi.

Immune System Functionality and the Plasma Membrane

The integrity of the plasma membrane is essential for cellular survival. a. Could the immune system utilize this fact to destroy foreign cells that have invaded the body? b. How might cells of the immune system disrupt membranes of foreign cells?

Parts of a Cell: Organelles

Choose the component of the cell that you think is most essential to the cell as a whole. Describe why you feel this way. Defend your choice.

What ingredients are needed for bread to rise?

Bread ingredients include milk, sugar, flour and salt. Which of these is needed for maximum fermentation by the yeast? What tests could be done in the lab? Will yeast react differently with different amounts of the other ingrediants? We did the lab and cut down the amounts of sugar, salt and milk. We had different results bu

Comparing the inner membrane of mitochondria

1. What two molecules do they have in common? 2. What two functions do they share? 3. How could I distinguish between the membrane of a mitochrondria and inner membrane of a chloroplast?

Cellular Respiration

If the conversion of pyruvate to lactate or ethanol and CO2 doesn't yield any energy for anaerobic cells, why do they do it? Please keep answer short and precise as possible!!!!!

Actual size of a cell based on drawing size and magnification is figured.

You have been given a picture of a cell. The magnification of the picture is 8000 X. The cell in this picture is 2 cm in length. Based on the information provided, this job determines what is the actual size of the cell? It also shows all relevant calculations and expresses the answer in micrometers.

Size of cell based on picture is determined.

You have been given a picture of a cell; the magnification of the picture is 8000 X. The cell in this picture is 2 cm in length. Based on the information provided, what is the actual size of the cell? Show all relevant calculations. (Express answer in micrometers) Ideas are then presented.

Potential Process Under Standard Conditions

The oxidation of FADH2 to form FAD: FADH2 (right arrow) FAD + 2H+ + 2e- this has a potential E (prime)=0.219 under biological conditions (pH=7.00) @ 298 K. What is the potential for this process under standard conditions? Please- I need a detailed explanation- not just numbers- I am using this as a study guide for my final

Mitochondria and Erythrocytes Red

Why are mitochondria and erythrocytes red? Please answer this question completely. I need a full understanding of why and how this occurs. Thank you

DNA mRNA Role of a Coenzyme

Consider the role of the coenzyme NAD in glucose oxidation. In the process of glycolysis the formation of pyruvate involves the reduction of the coenzyme NAD to NAD.2H. (a) Which other stages of glucose oxidation produce molecules of the reduced coenzyme, NAD.2H? (b) Explain what happens to NAD.2H produced during glycoly

Energy Requiring NAD.2H

The oxidation of NAD.2H is an energy -releasing process. Name the energy-requiring process it is coupled to, and explain why this is important for the cell (two or three sentences please).

NAD.2H During Animal Cell Production

Explain what happens to NAD.2H produced during glycosis 1) In an animal cell respiring aerobically, and 2) In an animal cell respiring respiring anaerobically I have already received an answer to this but I need a more simplified answer as I need to answer this in in more than 200 words.

Stages of Glucose Oxidation

In the process of GLYCOSIS (stage 1), the formation of PYRUVATE involves the reduction of the coenzyme NAD to NAD.2H Which other stages of glucose oxidation produce molecules of the reduced coenzyme, NAD.2H I am guessing at stages 2 & 3,