Which of the following is likely to be found in placer deposit

What role does water play in the process of building macromolecules? Why is it such an important component of life?

Lana71 [14]

Micro molecules all contain oxygen and hydrogen Cho Cho Chon c-carbon h-hydrogen o-oxygen cho cho chon is carbs fats proteins

5 0

3 years ago

What is the biochemical explanation for why adding glucose to a bacterial culture containing lactose significantly decreases pro

MatroZZZ [7]

Answer:

If we add glucose to the culture with lactose, the lac operon would be turned off and the production of beta-galactosidase, other enzymes and molecules that the operon transcribes, would decrease.

On the contrary, if we add lactose to a bacterial culture containing glucose, the lac operon would be on, transcribing the genes, hence, producing beta-galactosidase but only at a small rate. Because the bacteria already got the energy from the glucose.

Explanation:

An operon is a group of structural genes whose expression is regulated by a promoter, operator and regulator genes. In this particular case, they are talking about the lactose operon, lac operon. This operon is required, in bacteria, to obtain energy from lactose when there is no glucose present.

The lac operon contains a series of genes, lacZ, lacY, and lacA. The gene LacZ codifies an enzyme required to break the lactose, beta-galactosidase. LacY codifies for another enzyme required in the transport of lactose inward the cell. And finally, LacA produces a molecule that is involved in detoxification.

The lac operon is regulated, among others, by the presence of glucose and lactose. The glucose is the preferable source of energy for bacteria so if there are lactose and glucose the glucose would be used for energy at a bigger extent. In the absence of glucose, the lac operon plays a vital role and helps the bacteria to obtain energy from lactose.

When there is glucose but no lactose available, there is a repressor than binds to the promoter so the lac operon is OFF cannot express the genes.

On the other hand,when there is lactose and no glucose, lactose enters the cell and some of this molecules turn to alolactose. Alolactose molecules bind to the repressor so the operon is not repressed anymore and the lac operon would be ON producing enzimes and molecules.

If the lac operon is ON ( glucose absent ) the production of beta-galactosidase would be high, on the other hand, if the operon is OFF (glucose present) the production of beta-galactosidase decreases.

In the presence of both lactose and glucose, the genes for the lactose metabolisms are transcribed at low rates in the lac operon.

4 0

3 years ago

Consider this animal cell. The organelles in an animal cell are labeled. Part A is a structure with stacked membranes, part E re

dimulka [17.4K]

Answer:

G is a bean-shaped structure with folding inside

Explanation:

The Bean shape structure is the shape of Mitochondria, therefore it is the organelle of cellular respiration.

Kreb's Cycle and oxiadative phosphorylation are the major stages of of Cellular respiration which takes place in the mitochondria.

Cellular respiration is the process of extracting the energy as ATPs contained in foods(glucose, fatty acids, Aa) by combining them with oxygen.

Electron transport chains generate the energy for pumping protons to generate the energy, for ATPs synthesis, by enzyme ATPase synthases.

7 0

4 years ago

Read 2 more answers

The outer membrane contributes an extra barrier in gram-positive bacteria that makes them impervious to some antimicrobial chemi

dimaraw [331]

Answer:

The statement is false

Explanation:

Gram-positive bacterial cell wall is made up of only the peptidoglycan layer and it does not have an extra barrier that protects it from some antimicrobial chemicals. Gram-negative bacteria have two layers of cell wall peptidoglycan layer and a lipopolysaccharide layer.

So as gram-negative bacteria have an extra layer of cell wall therefore it is less sensitive towards antimicrobial chemicals than gram-positive bacteria. So grams positive bacteria are an easy target for antimicrobials than gram-negative bacteria. Therefore the statement is false.

4 0

4 years ago

What animals are biologically closest to humans?

Brilliant_brown [7]

Pigs I believe because we take organs from them to perform transplants

3 0

3 years ago