BIO 1140 Lecture Notes - Lecture 8: Cysteine, Histidine, Isoleucine

30 views4 pages

sapphirecod902

18 May 2016

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

In a cell these macromolecules interact with each other quite a bit. Their structure is going to influence their characteristics, their properties. That"s going to determine where they can be found in a cell. Where they can be found will determine how able they are to interact with other macromolecules. This will determine what type of tasks they can take on in a cell. Structural aspects of outer membrane- there are glycoproteins, glycolipids sticking out of the membrane to give the membrane and the cell something to be recognized on the outer cell. Cell recognition and communication- sugars attached to protein like stickies . On those proteins there can be small, relatively large carbohydrate molecules. Having those sugars stick out allow different cells that are in the neighbourhood to attach to our cell. It"s also part of recognition processes- for ex: antigens. Recognizing that a cell is a certain type.

Related Questions

1. Water's molecular structure of water gives rise to 4 emergent properties that facilitate life on earth. Explain how the molecular structure of water contributes to each of these properties.

Explain why the structure of carbon makes it an excellent backbone for the molecules that compose living organisms.

2. Explain how water is involved in the synthesis and breakdown of biological macromolecules. in your answer, make sure to discuss the reactions that join and break apart monomers and why water is related to these processes.

Saturated and unsaturated fats have different fluidities at room temperature. Explain why this occurs.

Use the structural differences discussed in part 1 to explain why one type of fat can harm the cardiovascular system while the other has little negative effects.

Given that starch and cellulose are both made from the same monomer, why do you think that cellulose is so much more difficult for animal digestive systems to break down?

Most living organisms are extremely sensitive to changes in temperature and pH.

Use your knowledge of protein structure and the bonds involved to explain this sensitivity. make sure to be specific about levels of structure and bonds that are disrupted when temperature or pH change significantly.

Some living organisms such as gut microorganisms able to survive in environments with extreme pHs. What kind of modifications may they have in the amino acid composition of their proteins that facilitate their adaptation to this environment?

3. Explain how the internal structure of a cell isolated from the pancreas differs from that of a muscle cell.,

Compare the structures of animal and plant cells. How are they different? how are they the same?

Edema is a medical condition that results from fluid leaking out of blood vessels into surrounding tissues. using your knowledge of animal cell junctions, hypothesize what type of junction may be malfunctioning in individuals suffering from edema and explain why you believe your hypothesis to be correct.

burgundyplatypus4

After working through the macromolecules in your friendâs extremely pale burrito, you look at her and think you might have an idea about what is going on. You ask Maria, âDo you usually eat like this?â âYup,â she says, âI love all the carbs, rice, and bread, as well as cheese. Sometimes I eat a piece of fruit or some carrot sticks. And energy drinks!â You then point out to your friend that she seems to be getting very little protein, a major class of macromolecules. But she is getting plenty of carbohydrates and lipids in the form of animal fats.

1. While your body can convert the monomers of macromolecules from one to the other, it has to have the raw materials in the form of the appropriate atoms. You explain to your friend that when she eats proteins, they are broken down into amino acids through the process of INSERT ANSWER and can then be rebuilt into new proteins through the process of INSERT ANSWER.

a. If your body does not take in protein, but only carbohydrates and lipids, what atoms will it be missing? Hint: There are two, and you can figure this out by comparing the structures of the monomers for proteins and carbohydrates as well as the basic structure of lipids. INSERT ANSWER

b. For the above atoms, how many electrons are in the outer shell? INSERT ANSWER

c. For the above atoms, what type of bond will they make within the amino acid monomer? INSERT ANSWER

d. Even if your friend does obtain the correct atoms, there are still a couple amino acids that your body cannot manufacture from scratch, but must be ingested. What are these amino acids? INSERT ANSWER

e.Why might a lack of protein or the wrong types of proteins lead to your friendâs fatigue? INSERT ANSWER

Class 6: Viruses (and Cells, continued)

Making connections: viruses and microbes Match the cell biology concept (on page 1) with an important application of that concept (on page 2). Then answer the follow-up questions at the bottom of page 2.

Cell Biology concepts
1. Bacteria that cannot construct new cell wall material become fragile and break down.
2. During influenza infection, the viral enzyme neuraminidase is required to release new viruses from the host cell in which they were made. Once released, the new viruses can infect many additional cells.
3. Thermus aquaticus is a bacterium found in hot springs and can live at temperatures up to ~80Â°C (175Â°F). It has adapted so that its enzymes are most functional at the elevated temperatures, compared with many organismsâ enzymes that function best ~37Â°C (98Â°F).
4. Until the isolation and investigation of retroviruses, scientists thought that RNA could be copied from DNA, but DNA could not be copied from RNA. Research on this class of viruses led to an update to this âCentral Dogmaâ of biology.
5. Some bacteria have adapted, so that the enzymes involved in making cell wall materials have a slightly different shape and can no longer be bound by certain drugs.
6. Rhizobia are bacteria that colonize the roots of certain plants (legumes, including beans and peas). The host plant benefits from the prokaryotesâ ability to âfixâ nitrogen, converting N2 from the atmosphere into a form that is usable by the plant.
7. Many species of bacteria contain the enzyme cellulase. More than 10 billion such bacteria and other symbiotic microbes may be found in a single milliliter of material from inside the digestive system of ruminant mammals.
8. Fungi, including those that cause athleteâs foot, use ergosterol to maintain healthy membranes. Animal cells do not make ergosterol, they use a similar lipid â cholesterol.
9. During retrovirus infection, a DNA copy is made of the virusâs RNA genome. A cut is made in the host cellâs DNA and the DNA copy of the viral genome is pasted into the host chromosome by a viral enzyme called integrase.
10. Prokaryotic cells contain smaller ribosomes (â70Sâ ribosomes) than eukaryotic cells (â80Sâ ribosomes). Both types of ribosomes synthesize proteins, but the macromolecules they use to do it are somewhat different.

2
Applications
_______ Oseltamivir, also called Tamiflu, binds and inhibits the viral protein neuraminidase.
_______ Clotrimazole is a drug that is used to treat certain infections. It interferes with synthesis of ergosterol, a lipid involved in phospholipid membranes.
_______ Penicillin is a drug that interferes with synthesis of peptidoglycans (these are biological molecules that are part protein and part carbohydrate) that are present in certain cell walls.
_______ HIV is often treated with several drugs that inhibit different parts of the viral replicative cycle. Raltegravir is an example of a drug that interferes with the integration of viral genes into the host cellâs chromosome.
_______ Cows, like other vertebrates, lack the ability to breakdown cellulose. Yet they are able to live on a diet of grass and other vegetation high in cellulose.
_______ Enzymes isolated from extremophiles have been very useful in laboratory research. For example, Taq polymerase facilitates PCR, a revolutionary technique for production of DNAs of particular sequences, which requires cycling reactions through high temperatures.
_______ Plants and animals require nitrogen to make biological macromolecules, however theyâre unable to convert atmospheric nitrogen (N2) into a biologically useful form.
_______ Azithromycin is a drug that binds to 70S ribosomes and blocks synthesis of any new proteins.
_______ Methicillin-Resistant Staphylococcus aureus (MRSA) can cause life-threatening infections of the skin and bloodstream. One of the reasons MRSA infections are so serious is that they are resistant to treatment by many antibiotics, including methicillin and penicillin.
_______ The enzyme reverse transcriptase, isolated from retroviruses, is an important tool in molecular biology research. Scientists interested in learning what genes are turned on in particular cells use it to make DNA copies of RNAs they are studying (The DNA copies are useful because they are more stable).

When you have completed the matching activity, answer these follow-up questions:
â¢ What types of infections can be treated with the following drugs?
o Penicillin
o Clotrimazole
o Azithromycin
o Tamiflu
o Raltegravir
â¢ Why are these drugs (above) safe for you to take? That is, why donât they kill your cells?
â¢ Cancer cells are your own human cells that have become deregulated so that they divide and pile up in an uncontrolled way. Many chemotherapy drugs treat cancer by interfering with cell division and other cell processes.
o Why are there so many more side effects for individuals undergoing chemotherapy than for individuals taking antibiotics?

BIO 1140 Lecture Notes - Lecture 8: Cysteine, Histidine, Isoleucine

Document Summary

Get access

Related textbook solutions

Molecular Cell Biology

Biology: Science for Life with Physiology

Biology

Concepts of Biology

Essentials of Biology

Related Documents

BIO 1140 Lecture Notes - Lecture 4: Covalent Bond, Chemical Bond

BIO 1140 Lecture Notes - Lecture 2: Beta Sheet, Cell Nucleus, Protein Structure

BIO 1140 Lecture Notes - Lecture 4: Carboxylic Acid, Dehydration Reaction, Amine

Related Questions