Deck 17: Developmental Genetics

Question 1

Cells becoming progressively more specialized in their structure and gene activity is known as:

A) morphogenesis.
B) determination.
C) differentiation.
D) maturation.
E) growth.

Answer 1

C

Question 2

Cells able to divide and form some types of cells in an organism are called:

A) pluripotent stem cells.
B) terminal differentiation cells.
C) determinate cells.
D) morphogenic cells.
E) developmental plastic cells.

Answer 2

A

Question 3

One of the main obstacles to successful cloning of sheep apparently overcome by Wilmut et al.was:

A) finding an adult nucleus that was likely to work.
B) synchronizing the cell cycles of the donor cell and the egg cell.
C) enucleating the donor cell.
D) the ability to culture cells in the laboratory.
E) recognizing that the nucleus from one sheep cell may contain different genetic information than the nucleus of another cell from the same animal.

Answer 3

B

Question 4

Undifferentiated cells that can divide and specialize to form a variety of different cells are called:

A) differential cells.
B) mother cells.
C) determinate cells.
D) stem cells.
E) morphogens.

Question 5

Differential gene expression is defined as:

A) the ability of some cells to arrest their development under different environmental conditions.
B) the progressive fixation of the fates of a cell's descendants.
C) the differences in the types of genes found in various somatic cells.
D) regulation during development that varies the type and quantity of gene products among cells.
E) the ability of some cells to constitutively express all their genes all the time.

Question 6

Cells become progressively committed to specific patterns of gene activity and developmental fate through a process known as:

A) morphogenesis.
B) determination.
C) cell differentiation.
D) nonspecific differentiation.
E) growth.

Question 7

The results of the experiment outlined in the accompanying figure clearly demonstrate:

A) gene amplification.
B) founder cell development pattern.
C) mosaic development.
D) apoptosis.
E) totipotency.

Question 8

Embryonic stem cells cannot develop into __________ cells.

A) muscle
B) nerve
C) blood
D) placental
E) other stem

Question 9

Cells become progressively organized into recognizable structures through a process known as:

A) morphogenesis.
B) determination.
C) cell differentiation.
D) nonspecific differentiation.
E) growth.

Question 10

Figure 17-4
Use this figure to answer the corresponding question(s).
Cloning mammals has proven to be:

A) impossible.
B) easy and straightforward.
C) not technically feasible at the present time.
D) a technique that produces many similar-looking, deformed progeny.
E) a process with a low success rate and a high incidence of genetic defects.

Question 11

Regulation of development takes place mostly at the level of:

A) replication.
B) transcription.
C) posttranscription.
D) translation.
E) posttranslation.

Question 12

The first cloned mammal, Dolly:

A) was stillborn.
B) developed arthritis and a virus-induced lung cancer at a relatively young age.
C) lived a short period of time before suffering advanced aging effects.
D) lived to a normal age for sheep.
E) lived longer than normal sheep.

Question 13

Totipotent human stem cells can apparently be obtained only from:

A) bone marrow.
B) umbilical cords.
C) cancer patients.
D) zygotes.
E) gametes

Question 14

The concept of nuclear equivalence states that:

A) all of the somatic cells in an adult organism have the same genes.
B) the genes of the individuals of the same species are exactly the same.
C) as cells mature, unneeded genes are lost.
D) the nuclei of all organisms are the same.
E) nuclei of individuals of the same species are the same size.

Question 15

Figure 17-4
Use this figure to answer the corresponding question(s).
In Figure 17-1, the purpose of growing the donor cells in nutrient-limited media is:

A) to have small cells that would be easier to manipulate.
B) to replicate a normal environment.
C) to force the donor cell nucleus into the G₀ cell stage.
D) to induce favorable mutations.
E) to initiate apoptosis.

Question 16

What evidence supports the idea that some nuclei are totipotent?

A) Nuclei taken from the cells of an embryonic frog can direct an egg to develop into a tadpole.
B) Nuclei taken from the cells of a frog embryo can direct an egg to develop into a tadpole.
C) Nuclei taken from a different species can direct a tadpole egg to develop into a normal tadpole.
D) Some cells are capable of undergoing unlimited cell cycles.
E) Some cells are capable of arresting their cell cycle at will.

Question 17

The significance of totipotency is that:

A) genes are not regularly lost during development.
B) most organisms can be easily cloned.
C) differentiation leads to the loss of certain genes in each cell.
D) somatic cells are incapable of differentiation.
E) unexpressed genes are lost during development.

Question 18

Figure 17-4
Use this figure to answer the corresponding question(s).
In Figure 17-1, the purpose of electrical shock at the stage of the process labeled A is to:

A) kill the egg cell nucleus.
B) initiate fusion of the two cells.
C) stimulate cell division.
D) induce mutations.
E) initiate apoptosis.

Question 19

Scientists are able to determine the location of cells expressing a certain gene in an embryo by:

A) the polymerase chain reaction.
B) blastoderm fate mapping.
C) gene mapping.
D) immunofluorescence.
E) multiple Southern blots.

Question 20

Totipotent nuclei are capable of:

A) controlling the expression of other genes in the nucleus.
B) directing normal development of an organism.
C) causing cells to lose the ability to differentiate.
D) undergoing unlimited nuclear divisions.
E) stopping the cell cycle at will.

Question 21

RNA interference is used to:

A) interfere with specific transcription factors.
B) knock out the expression of a specific gene.
C) prevent the duplication of DNA.
D) cause a mutation in a specific gene.
E) stimulate apoptosis.

Question 22

One characteristic that makes Caenorhabditis elegans attractive for developmental studies is:

A) its small, transparent body.
B) the extensive number of genes shared with humans.
C) the developmental defects that occur in this organism.
D) the close evolutionary relationship between this mammal and humans.
E) the presence of zygotic segmentation genes, similar to those found in humans.

Question 23

Developmental Drosophila genes, that when mutated cause the loss of alternate segments in the larva, are called:

A) embryonic segment genes.
B) larval segmentation genes.
C) segment polarity genes.
D) pair-rule genes.
E) gap genes.

Question 24

The only known source of human embryonic stem cells is:

A) placental tissue.
B) umbilical cords.
C) early human embryos.
D) brain tissue.
E) nerve tissue.

Question 25

Imaginal discs are:

A) found in mammalian cells and control gene activation in mature somatic cells.
B) paired groups of undifferentiated cells that are precursors of adult structures in Drosophila.
C) found in plant cells and assist in the development of the flower.
D) part of the salivary gland of Drosophila.
E) found in Drosophila ovary cells and represent inactivated X chromosomes.

Question 26

In early Drosophila development, which of the following forms first?

A) segmented larva
B) pupa
C) syncytial blastoderm
D) blastocyst
E) cellular blastoderm

Question 27

The first Drosophila segmentation genes to act are the __________, which begin organization of the body into regions.

A) pair-rule genes
B) segment polarity genes
C) gap genes
D) homeotic genes
E) maternal effect genes

Question 28

Most segmentation genes code for:

A) transcription factors.
B) genetic switches such as operators.
C) repressors.
D) insulin-like growth factors.
E) morphogens.

Question 29

Drosophila developmental mutants of __________ genes produce larvae with mirror image segments.

A) gap
B) pair-rule
C) segmentation
D) paternal effect
E) segment polarity

Question 30

Figure 17-12
Use the figure to answer the corresponding question(s).
Homeotic genes of Drosophila:

A) cause cells of the same type to produce differing amounts of gene products.
B) specifies the developmental plan for each part of each segment.
C) are expressed in only one sex in any particular species.
D) when mutated, cause body parts to be duplicated.
E) control developmental timing.

Question 31

Human therapeutic cloning would involve all of the following EXCEPT:

A) duplicating cells for scientific study.
B) duplicating cells for medical purposes.
C) making a new genetically identical individual.
D) transplanting the nucleus from a sick person into an enucleated egg cell.
E) extracting ES cells from an embryo.

Question 32

Figure 17-12
Use the figure to answer the corresponding question(s).
The mutation labeled 1 to the far right in Figure 17-2 is:

A) legs developing where antenna should be.
B) appendages of the eyes.
C) enlarged antennae.
D) newly formed structures to remove pollen or dust from the eyes.
E) a revision of the fly body so that legs and antenna have switched places.

Question 33

The role of maternal effect genes in Drosophila is to:

A) code for the production of yolk proteins.
B) prepare the female fly for reproduction.
C) control the early stages of Drosophila development.
D) control the development of the pupa.
E) control the shape and size of the eggs produced.

Question 34

Which of the following statements does not present a reason that Drosophila melanogaster is a suitable research subject for developmental genetics studies?

A) An abundance of developmental genes is available for study.
B) An abundance of mutants is available for study.
C) A new mutation can be mapped on the chromosome relatively easily.
D) Flies can be easily grown in the laboratory setting.
E) The control of fly development is unique and unrelated to human development.

Question 35

Gap genes of Drosophila embryos:

A) organize the embryo into broad regions and influence the activity of pair-rule genes.
B) are missing from the chromosomes of mutant flies.
C) are genes that have moved to gaps on other chromosome during meiosis.
D) cause gaps in the cell cycle.
E) cause the death of embryos before they hatch.

Question 36

Which of the following are not zygotic segmentation genes in Drosophila?

A) homeotic genes
B) gap genes
C) pair-rule genes
D) segment polarity genes
E) embryonic segment genes

Question 37

Maternal effect genes of Drosophila are genes active in __________ cells, whose products establish __________ in developing embryos.

A) maternal; gender
B) maternal; polarity
C) embryonic; polarity
D) embryonic; gender
E) egg; gender

Question 38

Analysis of many Drosophila maternal effect genes reveals that many are involved in:

A) female morphogenesis.
B) programmed cell death.
C) forming specific segments in the embryo.
D) nonspecific differentiation.
E) determining the polarity of the embryo.

Question 39

Maternal effect genes form gradients in the developing egg of chemicals called:

A) maternal Hox proteins.
B) segmens.
C) differens.
D) morphogens.
E) maternal growth factors.

Question 40

Figure 17-12
Use the figure to answer the corresponding question(s).
The mutant fly in Figure 17-2 illustrates all of the following except:

A) the existence of homeotic genes in Drosophila.
B) the concept of nuclear equivalence.
C) mutations in genes affecting segment identity.
D) an altered phenotype due to a mutant allele.
E) a structure containing many nuclei residing in a common cytoplasm

Question 41

Homeobox or homeobox-like genes are responsible for very similar developmental controls seen in all of the following organisms except:

A) Drosophila.
B) Arabidopsis.
C) C.elegans.
D) H.sapiens
E) E.coli

Question 42

What is the difference between a totipotent stem cell and a pluripotent stem cell? What piece of evidence would you need to distinguish them?

Question 43

Capases are __________ that are active in the first stages of __________.

A) genes; polarity establishment
B) genes; cancer
C) transcription factors; cancer
D) hormones; apoptosis
E) proteolytic enzymes; apoptosis

Question 44

How does the early development of the mouse differ from that of Caenorhabditis?

A) Embryonic mouse cells commit to their ultimate fate earlier than do the cells of Caenorhabditis.
B) Early development of a mouse is regulative, while early development of Caenorhabditis is not.
C) Mouse cells require higher concentrations of nutrients than do the cells of Caenorhabditis.
D) Embryonic mouse cells differentiate much later than the cells of Caenorhabditis.
E) Embryonic development in the mouse is controlled by transcription factors, while Caenorhabditis is not.

Question 45

Which of the following is characteristic of the developmental pattern referred to as mosaic development?

A) The cells of the adult are very different from each other.
B) The fate of adult cells is predetermined in embryonic founder cells.
C) Adult cells are richly interspersed with proteins.
D) Embryonic cells have a wide range of possible developmental patterns.
E) Embryos have a wide range of morphologies, but all look identical as adults.

Question 46

What would be the consequence of removing a founder cell early in the development of Caenorhabditis?

A) The organism would continue to develop normally.
B) The organism would develop normally but would be slightly smaller.
C) The organism would not develop at all.
D) The organism would be a hermaphrodite.
E) The structures that normally develop from that cell would be missing.

Question 47

Instances in which cells die shortly after they are produced in development is called:

A) morphogenesis.
B) type C determination.
C) apoptosis.
D) non-specific differentiation.
E) caspases.

Question 48

The ABC genes in the model of Arabidopsis flower development are organ-identity genes that are also:

A) segmentation genes.
B) homeotic genes.
C) gap genes.
D) translation factors genes.
E) growth factor genes.

Question 49

Which of the following DOES NOT identify a particular advantage in using Arabidopsis to study plant development and genetics?

A) The Arabidopsis genome has been sequenced.
B) Arabidopsis mutants can be easily induced with chemicals.
C) Many developmental mutants have been identified in Arabidopsis.
D) This plant completes its life cycle in just a few weeks.
E) It is a weed of no economic importance.

Question 50

Define and clearly differentiate between the following terms: cell determination and cell differentiation.

Question 51

__________ are organisms that contain two or more kinds of genetically dissimilar cells from different zygotes.

A) Heterozygotes
B) Chimeras
C) Recombinants
D) Transgenics
E) Polyploids

Question 52

Which of the following statements concerning proto-oncogenes is FALSE?

A) They are abnormal genes.
B) They code for growth factors.
C) They code for growth factor receptors.
D) They are involved in cancer.
E) They code for transcription factors.

Question 53

About __________ of the genes in a mouse have a similar gene in humans.

A) 10%.
B) 25%
C) 50%
D) 90%
E) 99%

Question 54

The __________ is a functional region found in certain proteins that are important in development.It consists of 60 amino acids that form 4 helices.

A) homeobox
B) homeodomain
C) homeogene
D) homeochromosome
E) functional group

Question 55

In the process known as __________, the fate of a cell is influenced by interactions with neighboring cells.

A) determination
B) induction
C) apoptosis
D) differentiation
E) pleiotropy

Question 56

Genes that normally block cell division are called:

A) growth factor genes.
B) oncogenes.
C) tumor suppressor genes.
D) proto-oncogenes.
E) growth inhibiting genes.

Question 57

Which of the following statements concerning metastatic tumors is FALSE?

A) They are examples of neoplasms.
B) They contain cancer cells.
C) They have escaped controls on cell division.
D) They are caused by the altered expression of genes.
E) They are localized in one part of the body.

Question 58

Malignant tumors are characterized by:

A) metastasis.
B) abnormal cell growth.
C) forming cell masses
D) specific mutations.
E) proto-oncogenes

Question 59

When the human gene coding for insulin is introduced into a mouse embryo, the gene is correctly expressed in the appropriate tissue.This shows that:

A) tissue-specific gene expression is highly conserved during evolution.
B) the introduced gene was edited by the mouse embryo for proper function.
C) the introduced gene was exactly the same as the mouse gene for insulin.
D) mice and humans are not closely related.
E) mouse genes are not tissue specific.

Question 60

Proto-oncogenes can be converted to oncogenes by:

A) mutation.
B) tumor suppressor genes.
C) growth factors.
D) transcription factors.
E) infection by certain viruses.

Question 61

Describe how maternal effect genes and segmentation genes work together in the early embryonic stages of Drosophila.

Question 62

Human reproductive cloning produces a newborn human that is genetically identical to another adult human.
_________________

Question 63

One way RNA interference molecules work is by selectively cleaving DNA molecules that have sequences complementary to small RNA molecules.
_________________

Question 64

Each homeobox codes for a protein functional region that binds to a specific DNA sequence and thereby affects translation.

Question 65

MATCHING
Sequence the steps that created the first cloned mammal and demonstrated that a differentiated mammalian cell has the genetic information to direct normal development.
a.in vitro culture of embryo
d.fuse mammary cell with enucleated egg cell
b.enucleate egg cell
e.live organism produced
c.transfer to host mother uterus
step 3

Question 66

MATCHING
Sequence the steps that created the first cloned mammal and demonstrated that a differentiated mammalian cell has the genetic information to direct normal development.
a.in vitro culture of embryo
d.fuse mammary cell with enucleated egg cell
b.enucleate egg cell
e.live organism produced
c.transfer to host mother uterus
step 4

Question 67

Adult stem cells in the brain are totipotent and differentiate into neurons and glial cells.
_________________

Question 68

MATCHING
Sequence the steps that created the first cloned mammal and demonstrated that a differentiated mammalian cell has the genetic information to direct normal development.
a.in vitro culture of embryo
d.fuse mammary cell with enucleated egg cell
b.enucleate egg cell
e.live organism produced
c.transfer to host mother uterus
step 1

Question 69

Pattern formation includes signaling between cells, changes in cell shape, and cell apoptosis.
_________________

Question 70

In animals, somatic cell lines are those that will undergo meiosis, differentiate into gametes, and be set aside early in development.
_________________

Question 71

A chimera is an organism containing two or more kinds of genetically similar cells from different zygotes.

Question 72

Define apoptosis and explain its role in normal development.

Question 73

MATCHING
Sequence the steps that created the first cloned mammal and demonstrated that a differentiated mammalian cell has the genetic information to direct normal development.
a.in vitro culture of embryo
d.fuse mammary cell with enucleated egg cell
b.enucleate egg cell
e.live organism produced
c.transfer to host mother uterus
step 2

Question 74

MATCHING
Sequence the steps that created the first cloned mammal and demonstrated that a differentiated mammalian cell has the genetic information to direct normal development.
a.in vitro culture of embryo
d.fuse mammary cell with enucleated egg cell
b.enucleate egg cell
e.live organism produced
c.transfer to host mother uterus
Describe and discuss the results of two experiments, one using plants and the other using animals, that support the totipotency of some cells.Emphasize the differences between manipulation of plant and animal cells in your discussion.

Question 75

A morphogen is a chemical agent that affects the differentiation of cells and the development of form.

Question 76

Mutations in segmentation genes cause one body part to be substituded for another body part.

Question 77

MATCHING
Sequence the steps that created the first cloned mammal and demonstrated that a differentiated mammalian cell has the genetic information to direct normal development.
a.in vitro culture of embryo
d.fuse mammary cell with enucleated egg cell
b.enucleate egg cell
e.live organism produced
c.transfer to host mother uterus
step 5

Question 78

What characteristics of Caenorhabditis elegans make it useful in molecular genetics studies?

Question 79

Scientists were able to produce induced pluripotent stem cells by introducing key DNA factors into mature mouse fibroblasts and human skin cells.
_________________