Identify which molecule or element is described below

Which one of the following is produced in the greatest numbers during one turn of the Krebs cycle?

Vitek1552 [10]

Answer:

The correct answer is - a. NADH

Explanation:

The Krebs cycle is a set of chemical reactions that takes place to generate energy from nutrients such as carbohydrates, fats, and proteins converting to carbon dioxide. by oxidation of acetate.

In the Krebs cycle, each molecule of carbon generates 3 molecules of NADH, one molecule of ATP and 2 molecules of FADH2 in each cycle. Thus, the greatest numbers during one turn of the Krebs cycle is NADH.

5 0

3 years ago

g Select true statements about three‑dimensional protein structures and their evolutionary relationships. Every species has only

vesna_86 [32]

Answer:

Every species has only unique proteins. FALSE

Determining sequence homology is an important tool for predicting protein structure and function. TRUE

Protein function is directly related to the protein's tertiary structure. TRUE

Protein function can be predicted from amino acid sequence. TRUE

The tertiary structure of a protein is more highly conserved than the primary structure. TRUE

Explanation:

Every species has only unique proteins. FALSE

There are homolog proteins among species, that share ancestry. It can be for a speciaton events, and this are called orthologs, or due a gene duplication event, and this are called paralogs.

Determining sequence homology is an important tool for predicting protein structure and function. TRUE

Sequence homology of an unknown protein can be useful since the primary structure can be used for modeling the protein structure, and also this information can be compared with databases of proteins of known function and retrieve predictive information about this protein function. Proteins with similar amino acid sequence usually do similar biochemical functions.

Protein function is directly related to the protein's tertiary structure. TRUE

In most cases, structure dictates the biochemical function of the protein. Protein functions are as diverse as protein structures.

Protein function can be predicted from amino acid sequence. TRUE

The primary structure (sequence of aminoacids) can lead to the elucidation of the secondary and tertiary structure of the proteins, since the sequence of the residues, and the nature of them (hydrophobic, aromatic, hydrophilic, basic, etc). This will shape the tridimensional form of the protein.

The tertiary structure of a protein is more highly conserved than the primary structure. TRUE

There can be changes in the amino acid sequences, but if they are amino acids of the same family, they will interact similar and maintain the tertiary structure with minimum changes.

3 0

4 years ago

How much energy is at the producer level?

Tems11 [23]

Explanation:

In a food chain, only 10% of energy is transferred from one trophic level to another trophic level. If the energy produced at the producer level is 1000 J, then the energy available at the primary consumer level will be 100 J and energy available at the secondary consumer level will be 10 J.

5 0

4 years ago

HELP ME PLEASE! Which of the following biomes would be LEAST stable? A. Tundra

vaieri [72.5K]

Answer:

Tundra

Explanation:

Ocean is the most stable biome, provides the majority of earths food and oxygen.

Rainforest provide 20% of earths food production. Also stable.

Grasslands although the don't get much rain it doesn't compare to the harsh weather that Tundra's face.

Tundra's is a very fragile environment. The freezing cold temperatures makes it a very difficult environment to survive in the winter, and plants and animals have a hard time coping with any extra stresses and disturbances. Therefore making it the least stable out of the rest listed.

3 0

3 years ago

Read 2 more answers

Silk is composed of β sheets whose polypeptide chains consist of the repeating sequence of Gly-Ser-Gly-Ala-Gly-Ala. Based on thi

DIA [1.3K]

Answer:

The correct answer is: d.a nonpolar side chain.

Explanation:

Protein can be defined as one of the factors which determine the structure as well as the function of a cell.
Proteins are composed of polymeric chains of polypeptides, which are made up of amino acid monomers linked to each other by peptide bonds.
Amino acids can be broadly categorised into non-polar and polar based on the nature of the side chain.
The non-polar amino acids possess hydrocarbon side-chains which are hydrophobic in nature, so they tend to avoid interaction with water molecules and usually remain in the protein interior. They are uncharged and cannot form any hydrogen bonds with water molecules.
The polar amino acids possess charged or polar side-chains which are hydrophilic in nature, so they tend to undergo interaction with water molecules and usually remain on the protein surface. They can form hydrogen bonds with molecules of water.
Beta sheets can be defined a secondary structure of the protein in which the polypeptide sequence forms horizontal strands which are linked to each other by loops. Each strand interact with each other by the formation of hydrogen bonds between the C=O group of one peptide (amide) bond in one strand with the N-H group of another peptide (amide) bond in another strand.
Apart from these bonds, the non-polar side chains of each amino acid in one strand forms hydrophobic or Van der Waals interactions with the non-polar side chains of each amino acid in the other strand. The polar or charged side chains of the amino acids on each strand form either hydrogen bonds with water molecules or with oppositely charged side chains.
In the given question, glycine and alanine are non-polar amino acids but serine is a polar amino acid. The side-chains of the non-polar amino acids will tend to face towards the interior of the beta sheet thereby forming hydrophobic interactions with each other, while the serine will tend to face the exterior of the beta sheet so that it can form hydrogen bonds with water molecules.
As the number of non-polar amino acids is far more than polar amino acids so the effect of non-polar amino acids will prevail in the beta-sheet.

5 0

3 years ago