Biology 101 Chapter 6 Review

Réussis tes devoirs et examens dès maintenant avec Quizwiz!

Which of the following statements most accurately describes the first law of thermodynamics?

Energy cannot be created or destroyed but it can be changed from one form to another.

Which of the following consistent with the laws of physics governing energy?

Eventually, sunlight that is absorbed on the earth returns to the atmosphere as dispersed heat

Which hypothesis, based on the two laws of thermodynamics as applied to cells, would determine if something is a living cell or no?

If something uses energy to make itself more organized, then it is alive.

Determine the accuracy of the following statement: A reactant will always produce the same type of product, regardless of the type of enzyme(s) present.

The statement is inaccurate because a particular reactant can be substrate for various enzymes, each resulting in a different product.

If there are 12 different intermediate products produced during production of a molecule in a cell, we can expect that there

are about 12 enzymes, at lest one responsible for each step in the metabolic pathway.

If an enzymatic reaction was controlled by feedback inhibition, we would expect it to stop

as soon as a critical level of end product builds up.

The metabolic pathways of photosynthesis and cellular respiration

both involve oxidation and reduction reactions

Which of the following is an example of chemical work within a cell?

building a protein

Most cells use a tremendous amount of ATP

but the amount of stored ATP is not great because our body constantly generates ATP from ADP+ P

The main reason that ATP is considered the energy currency in cells is because it

contains accessible energy in phosphate bonds

Chemical reactions that require an input of energy are

endergonic reactions

What is the equation for photosynthesis?

energy + 6CO2 + 2H2O --> C6H1206 + 602

When a cell uses substantial energy to organize its cell contents to a greater degree that the organization that exists outside the living cell

entropy is decreased

Enzymes have "specificity". This means that they

have a particular substrate

Each enzyme has a particular substrate because enzymes

have active sites complementary in shape to their substrates.

The function of an enzyme is to

increase the rate of a metabolic reaction.

Heat

is an unusable form of energy

Which of the following molecules is an enzyme?

lipase

Which of the following by-product of photosynthesis?

oxygen

A reaction that is "endergonic, anabolic, nonspontaneous, and has a positive delta G" could be describing

photosynthesis

Most enzyme are

protein molecules

The addition of electrons and/or hydrogen from a substrate is called what?

reduction

Enzymes

require coenzymes and/or cofactors for optimal functioning

Whether or not an enzyme is present and active within a cell depends on all of the following except

the presence of specific steroids in the cytoplasm

The ultimate source of energy for the majority of organisms on Earth is

the sun.

In feedback inhibition of a metabolic pathway, where does the inhibitor bind?

to the enzyme of the first reaction

Which of the following will increase enzyme activity?

Change to optimum pH for the reaction

Which of the following is a true statement regarding energy and chemicals

Chemicals, but not energy, may cycle through living things

ATP can be broken down into

ADP plus phosphate plus energy

Chloroplasts and mitochondria are both involved in redox reactions because

Carbon dioxide is reduced during photosynthesis and carbohydrates are oxidized during cellular respiration

Which statement most accurately describes the second law of thermodynamics?

Energy cannot be changed from one form to another without a loss of usable energy

Which of the following is an accurate statement about metabolic pathways?

Metabolic pathways often intersect one another.

Where within the cell is the majority of ATP produced?

Mitochondria

Which of the following is a correct statement about the second law of thermodynamics and entropy?

The amount of disorder in the universe is always increasing

Assess the following statement for accuracy; All of the energy that a plant stores in the bonds of glucose is available to an animal to power its muscles

The statement is inaccurate because the second law of thermodynamics states that energy cannot be converted from one form to another without a loss useable energy.

Which of the following statements is true about enzymes?

They catalyze only one specific type of reaction

Assess the following statement for accuracy: Because the inside of a cell is more organized that the outside, the inside of the cell has increased entropy

This statement is inaccurate because as order increases, entropy decreases.

Which of the following is a true statement regarding oxidation reactions?

Whether or not oxygen is involved, a reaction is considered and oxidation reaction if elections are lost.

We often say that we need food for energy. Ina biological sense, is that correct?

Yes, because the food we eat has potential energy in its structure and this chemical energy can be converted into mechanical.

What is a metabolic reaction called that involves one reaction releasing energy to provide energy for a second reaction that requires energy?

a coupled reaction

What is a metabolic reaction called that involves one reaction releasing energy to provide for a second reaction that requires energy?

a coupled reaction

The location in which the enzyme and the substrate complex is called the

active site

Which of the following is not cellular function of ATP?

adding structural integrity to the cell membrane

The term metabolism refers to

all the chemical reactions that occur in a cell

ATP contains

an adenine base, a ribose sugar, and three phosphate groups

In a coupled reaction

some of the energy released in one reaction is used to drive another reaction forward

The reason an increase in substrate concentration does not increase the reaction rate indefinitely is because

the active site will become saturated with substrate and the enzyme will not be able to go any faster.

While science cannot describe "thinking" in physical terms, we are certain that the process involves metabolism inside brain cells. With positron emission tomography (PET scan), it is possible to inject short-lived isotopes and image the regions of the brain that have the most active metabolism during various mental activities. However

the cellular energy expended in thinking must be less that the chemical bond energy supplied in food to these brain cells.

The specificity of an enzyme to a substrate is currently best explained by

the induced-fit model


Ensembles d'études connexes

First Aid Ch.13 Chest, Abdominal & Pelvic injuries

View Set

Chapter 14 Lesson 3 Southern Cotton Kingdom

View Set

Acc201 Chapter 6 Interactive Quiz

View Set

Ankle and Foot: Part 4 (Insufficient Dorsiflexion)

View Set

The Endocrine Pancreas and Glucose Regulation

View Set

Chapter 43: Assessment of Digestive and GI function Prep-U

View Set

Peds - Chapter 31: Health Supervision

View Set