AP Bio semester 1

Study guide using past test/quiz questions

What are the end products of photosynthesis?

Oxygen and Carbhydrates

Which is most closely associated with the Calvin cycle?

carbon dioxide fixation

A product of photosynthesis, __________, is the chief source of energy for most organisms.

glucose

Oxygen production in photosynthesis involves all of the following EXCEPT

photosystem one

During the light reactions what structure is responsible for absorbing the solar energy?

chloroplast

Which of these is NOT a major photosynthetic pigment in plants?

chlorophyll c

The function of sunlight in photosynthesis is to:

excite electrons in chlorophyll

The light-dependent reactions of photosynthesis occur in the stroma of the chloroplast.

False

_______ is a product of the Calvin Cycle that is used to form glucose phosphate, amino acids or fatty acids.

G3P (glyceraldehyde-3-phospate)

The major enzyme that 'fixes' carbon dioxide is called

ribulose bisphosphate carboxylase (rubisco).

Photorespiration occurs mainly in:

C3 plants

Which of the following plants is an example of a CAM plant?

cactus

While C-4 plants have carbon dioxide fixation and carbon dioxide uptake separated by location within the plant, CAM plants

have these processes separated by time.

Photorespiration is the process by which light is used to release the stored energy in carbohydrate molecules to perform all work in plant cells.

False. Photorespiration is the process whereby the enzyme RuBisCO oxygenates RuBP, leading to the production of a glycolate, which can lead to energy loss in C3 plants.

Which of the following pairs is correct?

C4 plants: bundle sheath cells contain chlorophyll

Complete oxidative breakdown of glucose results in ______ ATP molecules.

36

Which process produces both NADH and FADH2?

citric acid cycle

During glycolysis _____ carbons will enter the pathway but _____ carbons will leave in the form of pyruvates.

6 & 6. One 6-carbon glucose molecule enters the pathway and is broken down into two 3-carbon pyruvate molecules, meaning all 6 initial carbons are accounted for in the products

Glycolysis will yield a net of 2 ATP only during aerobic respiration.

False

Which of the following organelles modifies and packages for secretion the materials produced by the ribosomes?

Golgi apparatus

A student using a light microscope observes a cell and correctly decides that it is a plant cell because

it has a large central vacuole

Plant stems bend toward a light source as a result of increased

cell elongation on the side of the stem away from the light source

During respiration, most ATP is formed as a direct result of the net movement of

protons down a concentration gradient

Which of the following processes is carried out more efficiently by a C₄ plant than by a C₃ plant?

Fixation of CO2

Glycolysis occurs before fermentation.

true. is the initial stage of cellular respiration, breaking down glucose to produce pyruvate.

Why would an organism utilize alcohol fermentation if it is wasteful of the energy in food molecules and poses a threat of death due to high levels of toxic alcohol?

All of the choices are advantages

Degradative reactions

can drive anabolism.

These reactions involve the breakdown of complex molecules into simpler ones, releasing energy that can be used for cellular activities.

For fatty acids to enter the citric acid cycle of aerobic respiration, the fatty acids must be:

converted to acetyl groups.

Adult humans cannot synthesize _____ out of the _____ common amino acids.

9/20

Which best describes the second law of thermodynamics?

Some useful energy is lost as heat whenever an energy transfer occurs.

ATP is considered a high-energy compound because under cellular conditions, 7.3 kcal per mole of energy is released when a bond is broken between:

the adenosine diphosphate and the third phosphate.

A coenzyme is

a nonprotein organic cofactor that interacts with an enzyme to allow it to work.

The term stroma refers what?

the central fluid-filled space of the chloroplast

Which of the following statements about the Calvin cycle is correct?

the CO2 is absorbed and reduced to CH2O

The major enzyme that 'fixes' carbon dioxide is called

ribulose bisphosphate carboxylase (rubisco).

When the stomata in a leaf close during the day, then

All choices but the halting of photosystems are correct.

The first phase of aerobic cellular respiration is:

glycolysis

The membrane protein (enzyme) _________ will transform ADP + P  ATP as H⁺ flow down a gradient from the intermembrane space into the matrix.  

ATP synthase

The amino acids we cannot synthesize are called _____ because we _____.

essential; must include them in our diet

Which of the following is NOT true concerning mitosis?

Animal cells form a cell plate during cytokinesis while plant cells do not.

If a parent cell has 48 chromosomes, how many chromosomes will each daughter cell have after mitosis and cytokinesis occurs?

48

Which is NOT true about the chromosomes of a multicellular organism?

Each chromosome separates into two daughter chromosomes by binary fission.

In some organisms, mitosis occurs without cytokinesis. This results in:

a multinucleated cell

Cancer cells require many nutrients, which are supplied by blood vessels. The growth of new blood vessels to cancerous tissue is called:

angiogenesis

Oncogenes are all of the following EXCEPT:

tumor suppressor genes

Which is NOT correctly associated with cancer?

The disorganized mass of cells is encapsulated and does not invade adjacent tissue.

Although cancer may originate in many regions of the body, many patients die from cancerous growth in the lungs, lymph glands, or liver. This is most readily explained as

metastasis occurring more commonly in organs that have a filter effect.

Which of the following is NOT true about cancer cells?

They exhibit contact inhibition.

The region that contains the genetic information in a bacterial cell is called the

nucleoid

Eukaryotic chromosomes

All of the choices are correct.

Which statement is NOT true about eukaryotic chromosomes?

There is only one chromosome of each type in each body cell.

Binary fission in bacteria differs from mitosis because

All of the choices are correct.

Which statement below lists the correct steps for binary fission?

1. attachment of chromosome to the plasma membrane

2. enlargement of cell volume

3. DNA replication occurs

4. cell elongates and chromosomes are pulled apart

5. a new cell wall and plasma membrane divide the cell in half

If the diploid number of chromosomes for an organism is 52, what will the haploid number of chromosomes be?

26

Another name for a tetrad is a/an

bivalent

Homologous chromosomes are similar in all of these characteristics EXCEPT:

carry the same alleles for all traits.

The overall function of meiosis includes all of the following EXCEPT

growth of the overall individual.

Which statement is NOT true about homologues in meiosis I?

Each homologue's centromere splits to form two chromosomes.

Which of the following steps would NOT lead to variation of genetic material?

crossing over of sister chromatids

To what does the term chiasma refer?

a structure that holds together homologues during crossing-over

During _______________ the homologous chromosome pairs separate in a random fashion leading to genetic diversity among the offspring.

independent assortment

There is a species of desert lizard where only females are known to exist-there are no males known. It is nevertheless necessary for two females to court and for one to assume the posture of a male to stimulate the female to produce eggs. No fertilization can occur, and the eggs develop into female lizards. What is the probable evolutionary mechanism for this occurring?

The desert is relatively uniform and there is little advantage to maintaining variation, but the animal has not been able to completely evolve away from its heritage of sexual reproduction.

Species X reproduces asexually by fission and species Y reproduces sexually. Consider that all other relevant characteristics are similar between these species. When the environment changes, then

species Y should have a better chance of surviving than species X.

At which stage of meiosis is each chromosome composed of a single chromatid?

anaphase 2

Which does NOT occur in meiosis?

two daughter cells at completion

Identify which event will occur during Prophase I of meiosis but does not occur during prophase of mitosis.

bivalents will form

Interkinesis is different from interphase in which way?

Interphase involves DNA replication and interkinesis does not.

Meiosis occurs during all of the following EXCEPT

pangenesis.

Where in the human male does spermatogenesis occur?

testes

Which of the following statements is true about the life cycle of animals?

The gametes are the haploid phase of the animals life cycle.

All of the following are true concerning Down Syndrome EXCEPT

chances of a woman having a child with Down Syndrome decreases with her age

The cell formed through fertilization of an egg by a sperm is called a/an

zygote

Which of the following occurs during mitosis but not during meiosis I ?

The chromatids of each chromosome are separated.

The rate of division of most vertebrate cells is LEAST likely to be influenced by which of the following?

The cell's photoperiod

What occurs in anaphase?

Chromosomes move to opposite poles.

What is the importance of crossing-over?

It increases the likelihood that daughter cells contain different genetic material.

The only haploid cells in the human body are the _____.

sperm and egg

Numerous animals, notably reptiles, are capable of reproduction and maintaining numbers when populations are composed of only single sex members, even in isolated areas. How do you explain this statement?

Meiosis within unfertilized eggs will arrest at a diploid stage and undergo normal fetal development in an all-female population.

Which of the following reasons helped make Mendel successful with his genetic experiments?

All of the above.

If a pea plant shows a recessive phenotype,

the genotype can only be tt.

What are alleles?

alternative forms of a gene for a single trait, such as blue eyes or brown eyes

Which is NOT true according to Mendel's law of segregation?

One factor must be dominant and one factor recessive in each individual.

Some plants fail to produce chlorophyll, and this trait appears to be recessive. Many plants also self-pollinate. If we locate a pea plant that is heterozygous for this trait, self-pollinate it and harvest seeds, what are the likely phenotypes of these seeds when they germinate?

About one-fourth will be white and three-fourths green since it is similar to a monohybrid cross between heterozygotes.

Women with X-linked disorders always pass the genes for the disorder to ______, while men with X-linked disorders always pass the genes for the disorder to _______.

both their daughters and sons; only their daughters

Haiti is settled by peoples of both African and European ancestry. A young couple, both with mixed ancestry, marry and have several children. The children vary widely in the amount of skin melanin production, with one child being lighter than both parents, and one being darker. The simple explanation for this is

polygenic inheritance.

The reason why some individuals who inherit polydactyly (having an extra digit on the hand or feet) but do not express the trait is due to ________.

incomplete penetrance

If a woman is a carrier for the color-blind recessive allele and her husband is normal, what are their chances that a son will be color-blind?

50% since the mother is the only carrier.

Pleiotropy typically

causes various symptoms to appear even though it only impacts a single gene.

Which of the following statements is NOT true about the debate over the nature of genetic material?

Scientists focused on carbohydrate and protein in their studies of possible genetic material since they knew that genes were on chromosomes and that chromosomes were made of carbohydrate and protein.

If a DNA sample contains 13% adenine, what percentage of the sample contains cytosine?

37%

The X-ray diffraction photography of Rosalind Franklin and Maurice Wilkins was critical evidence in the study of DNA,

indicating that DNA has a double helix structure.

Which statement is NOT true about DNA replication?

DNA can only replicate at one point on a chromosome at one time.

Which of the following statements applies to the semiconservative nature of DNA replication?

The old strands serve as a template for the new strand.

Which is NOT true about the genetic code?

Most amino acids have only one codon.

Codons:

All of the choices are correct.

Determine the number of codon sequences it would require to produce the following amino acid sequence: alanine - proline - serine - isoleucine - stop.

It would take 5 codon sequences.

Transcription is initiated when:

RNA polymerase binds to a region of DNA called the promoter.

Which of the following would be transcribed into mRNA?

a protein-coding gene

The correct sequence of events in translation is:

initiation, elongation, termination.

For translation to take place, which of the following would NOT be required to be present?

DNA