Answer:
A). The complementary shapes of an enzyme and a substrate.
Explanation:
The Lock-and-key mechanism was proposed by Emil Fischer for the first time and characterized as the metaphor which helps in elucidating the specificity of the enzymatic reactions. In this metaphor, the lock is described as the enzyme while 'key' is characterized as the substrate which the enzyme acts upon. If the key is not appropriately sized, it will not fit into the active site i.e. the keyhole of the lock or enzyme and reaction will not take place. Thus, <u>option A</u> is the correct answer.
Prokaryotes are usually unicellular - and so would not have tissue, organs or organ systems.Some prokaryotes are multicellular, and you could potentially say that they are a tissue (many similar cells working together to perform a task). However, no prokaryotes have organs or organ systems.
A calcium atom has 20 protons!
There you go! I really hope this helped, if there’s anything just let me know! ☻
Answer:
<em>17500 calories</em> of chocolate bars are needed to eat to gain 5 pounds.
Explanation:
We can use ratios to calculate the answer using the information given in the question.
1 pound : 3500 grams
5 pounds : x grams
As it is given that the individual is burning no calories, we do not have to factor in any additional numbers.
<u><em>Method</em><em> </em><em>A</em><em>:</em></u>
To go from 1 in the first ratio to 5 in the second ratio, they multipled 1 by 5. Hence, to go from 3500 in the first ratio to x in the second ratio, we must multiply by 5.
x = 3500 × 5
x = 17500
<em><u>Method B</u>:</em>
To solve for the answer x, we can convert the ratios into fractions.
1 / 5 = 3500 / x
3500 / x = 1 / 5
To make x the subject, multiply the denominator of the left fraction with the numerator of the right fraction and place it on the left side. Then multiply the numerator of the left fraction with the denominator of the right fraction and place it on the right side.
x = 5 × 3500
x = 17500
Answer:
B) the chemicals are gaining energy from the surroundings.
Explanation:
The positive sign of the energy difference in a chemical reaction would indicate that the chemicals are gaining energy from the surroundings. This is what happens in an endothermic reaction.
In an endothermic reaction, heat is absorbed from the surroundings hence the surrounding becomes colder at the end of the changes.
- Here the energy change is assigned a positive value.
- This is because the heat energy level of the final state is higher than that of the initial state.
- So, the difference gives a positive value.