unit 3

either the mother or father

You are looking at chromosome 1 in a human being. Assuming there is no crossing over, what is the source of all the genes on this chromosome?

one functional egg is produced.

A basic difference between spermatogenesis and oogenesis is that in oogenesis

false

A reactant will always produce the same type of product, regardless of the enzymes present.

ADP plus phosphate plus energy

ATP can be broken down into

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

ATP contains

metaphase

In which stage of mitosis do the chromosomes line up in the center of the cell?

false

Centrioles are necessary to the process of mitosis in all organisms.

endergonic reactions

Chemical reactions that require the input of energy are

G2 phase

Upon examination, a cell is found to have twice as much DNA as the normal diploid state but is no longer in the process of replicating the DNA. All of the DNA is found within a single nucleus. Which stage of the cell cycle is this cell in?

The enzyme and the substrate form a temporary complex.

During an enzymatic reaction, what happens to the enzyme?

chromatids exchange segments of genetic material.

During cross-over,

hereditary material duplicates itself.

During interphase,

anaphase I

During what stage do homologous chromosomes separate from each other?

anaphase II

During what stage of meiosis do sister chromatids separate from each other?

prophase

During what stage of mitosis does the nuclear envelope disappear and the chromosomes become distinct?

anaphase I

During which phase will homologous chromosomes separate?

prophase, metaphase

During which phases of the cell cycle do the chromosomes look like Xs?

interphase

During which stage of the cell cycle do the chromosomes duplicate?

have active sites complementary in shape to their substrates.

Each enzyme has a particular substrate because enzymes

have a particular substrate

Enzymes are specific. This means that they

false

Enzymes maintain their same shape when they bind to a substrate.

chromatin

Eukaryotic chromosomes are composed of

mitosis

Following a cut or scrape, which process repairs your skin?

false

Heat is not a form of energy.

The cell plate is the final partitioning of plant cells.

How does cell division differ between animal and plant cells?

a product

If A → B → C → D → E represents a metabolic pathway, then letter E would be

there is DNA damage

If a cell stops at the G1 checkpoint, this is most likely due to what problem?

they would consist of 100 pairs with one of each pair from the father, one of each pair from the mother.

If a crayfish has 200 total chromosomes in its body cells (not ovaries or testes),

8

If the diploid chromosome number is 16, the chromosome number of each gamete will be

six chromosomes in each daughter cell.

If the total number of chromosomes in a cell is six, then after mitosis there will be

decrease the temperature

If you wished to increase enzyme activity, you would do all of the following except

true

In a coupled reaction, some of the energy is not released to the environment because the energy from one reaction is used to drive the other reaction forward.

to the enzyme of the first reaction

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

46

In humans, the diploid number of chromosomes is

true

Less energy is needed to bring about a reaction when an enzyme is present.

2n to n

Meiosis results in a change in chromosome number indicated by

protein molecules

Most enzymes are

he second law of thermodynamics.

Occasionally someone claims to have built a machine that can run forever, producing as much energy as it consumes. This has always been disproved because it violates

enzyme inhibitors

Poisons are often

false

Since enzymes are not used up during a reaction, they do not play any role in the reaction.

Prophase I

Synapsis occurs during what stage of meiosis?

false

The addition of an enzyme will change the end result of a reaction. In other words, a particular reaction will result in a different product if an enzyme is used.

mitosis and interphase

The cell cycle consists of

true

The chromatids are held together at a region called the centromere.

spermatogenesis

The formation of sperm gametes is termed

increase the rate of a metabolic reaction.

The function of an enzyme is to

the phosphate groups.

The high energy bond in ATP is found in or between

active site

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

contains accessible energy in phosphate bonds.

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

mitosis and cytokinesis

The mitotic stage of cell division consists of

telophase

The nuclear membrane reappears in mitosis during

true

The only haploid stage in the animal life cycle is the gamete.

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

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

haploid

The second meiotic division is essentially a mitotic division except for the fact that the cells produced are

the induced-fit model

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

true

The term "metabolism" refers to all of the chemical reactions that occur in a cell.

being a structural component of the cell membrane.

The various uses of ATP include all of the following except

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

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

a coupled reaction

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

entropy has decreased

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

true

When heat dissipates into the environment, it is no longer usable by the individual who produced it.

mitochondria

Where within the cell is ATP built up?

Kinetic energy is energy of motion.

Which energy association is correct?

interphase-shortest stage of the cell cycle

Which is NOT a correct association? G1 stage-cell grows in size and cell organelles increase in number M stage-mitosis and cytokinesis S stage-DNA synthesis G2 stage-metabolic preparation for mitosis interphase-shortest stage of the cell cycle

mitosis-when a cell duplicates and then divides twice to reduce chromosome number by half

Which is NOT a correct association? mitosis-when a cell duplicates and then divides twice to reduce chromosome number by half sister chromatids-two identical chromosome strands still attached at the centromere cytokinesis-division of the cytoplasm centromere-point where sister chromatids remain attached haploid-one of each chromosome

Adding the correct enzyme can lower the energy of activation.

Which is true about energy of activation? Energy of activation is the difference between the energy of the reactant and the energy of the product. Energy of activation is measured as the energy that is released after a reaction occurs. Adding the correct enzyme can lower the energy of activation. The energy of activation is always lower than the energy of the reactant. In any one metabolic pathway, all steps will have the same energy of activation.

sister chromatids

Which of the following are genetically identical? both members of a pair of chromosomes the mother's and the father's chromosomes the father's and his child's chromosomes the mother's and her child's chromosomes sister chromatids

Apoptosis plays a normal role in development and cancer prevention.

Which of the following best characterizes apoptosis? Apoptosis happens accidentally to healthy cells. Apoptosis results in our going from a fertilized egg to trillions of cells. Apoptosis is bad for an organism. The stages of apoptosis are different in each cell type. Apoptosis plays a normal role in development and cancer prevention.

The first checkpoint is located in the S phase of interphase.

Which of the following is not true concerning the checkpoints in the cell cycle? Mitosis stops if chromosomes are not properly aligned. The first checkpoint is located in the S phase of interphase. Mitosis will not occur if DNA is damaged or not replicated. Cyclins must be present at certain stages to advance to the next stage. If DNA is damaged, apoptosis may occur.

S-G2-M-G1

Which of the following is the correct sequence for the cell cycle? S-G1-G1-M S-G1-M-G2 S-M-G1-G2 S-M-G2-G1 S-G2-M-G1

lactose

Which of the following molecules is NOT an enzyme? ribonuclease lipase maltase urease lactose

As the temperature increases, most enzymatic reactions will still proceed at the same rate.

Which of the following statements is not true concerning enzymatic activity? Each enzyme has a preferred pH at which the enzyme reaction rate is highest. As the temperature increases, most enzymatic reactions will still proceed at the same rate. Enzymatic reactions proceed quite rapidly. Enzyme activity increases as substrate concentration increases until the maximum rate is achieved. Above a certain temperature, an enzyme will become denatured.

They catalyze only one specific type of reaction.

Which of the following statements is true about enzymes? Their 3D shape can vary and still be active. They can associate with a wide variety of substrates. They are unaffected by changes in pH. They catalyze only one specific type of reaction. Boiling temperatures do not affect their activity

Energy can be neither created nor destroyed but it can be changed from one form to another.

Which of the following statements most accurately describes the first law of thermodynamics? One usable form of energy cannot be completely converted into another usable form. One usable form of energy can be completely converted into another usable form. Energy cannot be transformed. Energy can be neither created nor destroyed but it can be changed from one form to another.

prophase, metaphase, anaphase, telophase

Which sequence of stages in mitosis is correct?

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

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. Energy cannot be created or destroyed. One usable form of energy can be completely converted into another usable form. Energy cannot be created nor destroyed but it can be changed from one form to another. Energy cannot be transformed.

No, since crossing-over does not occur between sister chromatids.

Would it be possible to observe crossing-over between sister chromatids? Why or why not?

a cleavage furrow

You are examining a cell under the microscope that is undergoing cell division and cannot find any asters. What else would not be present in this cell?

anaphase I

You are looking at a cell under the microscope, and see what appears to be several "X" structures being pulled to each side of the cell. What stage of meiosis are you looking at?