Question 1

When is a cell considered differentiated?

Accepted Answer

A) when a cell first becomes irreversibly committed to a particular fate 
B) when a cell begins its pattern formation 
C) when a cell manufactures proteins that are specific to a particular cell type 
D) when a cell is part of recognizable tissues or organs 
A) when a cell first becomes irreversibly committed to a particular fate 
B) when a cell begins its pattern formation 
C) when a cell manufactures proteins that are specific to a particular cell type 
D) when a cell is part of recognizable tissues or organs

Question 2

Suppose the pair-rule genes were inactivated in Drosophila embryos.What is the likely result of the experiment?

Accepted Answer

A) The embryos would develop normally. 
B) The embryos would lack several segments. 
C) The embryos would have impaired anterior-posterior polarity. 
D) The embryos would have missing alternate segments. 
A) The embryos would develop normally. 
B) The embryos would lack several segments. 
C) The embryos would have impaired anterior-posterior polarity. 
D) The embryos would have missing alternate segments.

Question 3

What was the experimental purpose of the preliminary genetic screening performed in which Nüsslein-Volhard and Wieschaus exposed adult fruit flies to treatments that would cause mutations in their offspring?

Accepted Answer

A) to evaluate the mutagenic properties of varied treatments 
B) to discover the bicoid gene 
C) to generate two-tailed fruit-fly embryos 
D) to identify fruit flies with mutations in genes that control fruit-fly development 
A) to evaluate the mutagenic properties of varied treatments 
B) to discover the bicoid gene 
C) to generate two-tailed fruit-fly embryos 
D) to identify fruit flies with mutations in genes that control fruit-fly development

Question 4

Animal species exhibit an enormous diversity of genetic information contained in nuclear DNA.This difference in DNA may be reflected in very different genome sizes.Scientists investigating the possibility that animals with more complex morphological structures might express greater numbers of different types of mRNAs during development found that similar numbers of genes were transcribed at a particular time in development in species whose genome sizes differed greatly in size.How can this result be interpreted?

Accepted Answer

A) Some species retain large amounts of DNA that are never used. 
B) The number of genes transcribed at any one time is tightly regulated,independent of genome size. 
C) Genome size has nothing to do with the physical complexity of the species. 
D) Nuclear DNA complexity is unrelated to the complexity of mRNAs transcribed during development. 
A) Some species retain large amounts of DNA that are never used. 
B) The number of genes transcribed at any one time is tightly regulated,independent of genome size. 
C) Genome size has nothing to do with the physical complexity of the species. 
D) Nuclear DNA complexity is unrelated to the complexity of mRNAs transcribed during development.

Question 5

The protein of the bicoid gene in Drosophila determines the _____ of the embryo.

Accepted Answer

A) anterior-posterior axis 
B) anterior-lateral axis 
C) posterior-dorsal axis 
D) posterior-ventral axis 
A) anterior-posterior axis 
B) anterior-lateral axis 
C) posterior-dorsal axis 
D) posterior-ventral axis

Exam 21: Principles of Development

When is a cell considered differentiated?

Suppose the pair-rule genes were inactivated in Drosophila embryos.What is the likely result of the experiment?

What was the experimental purpose of the preliminary genetic screening performed in which Nüsslein-Volhard and Wieschaus exposed adult fruit flies to treatments that would cause mutations in their offspring?

The protein of the bicoid gene in Drosophila determines the _____ of the embryo.

Biology and the Tree of Life

Water and Carbon: the Chemical Basis of Life

Protein Structure and Function

Nucleic Acids and the Rna World

An Introduction to Carbohydrates

Lipids, membranes, and the First Cells

Inside the Cell

Cell-Cell Interactions

Cellular Respiration and Fermentation

Photosynthesis

The Cell Cycle

Meiosis

Mendel and the Gene

Dna and the Gene: Synthesis and Repair

How Genes Work

Transcription and Translation

Control of Gene Expression in Bacteria

Control of Gene Expression in Eukaryotes

Analyzing and Engineering Genes

Genomics

An Introduction to Animal Development

An Introduction to Plant Development

Evolution by Natural Selection

Evolutionary Processes

Speciation

Phylogenies and the History of Life

Bacteria and Archaea

Protists

Green Plants

Fungi

An Introduction to Animals

Protostome Animals

Deuterostome Animals

Viruses

Plant Form and Function

Water and Sugar Transport in Plants

Plant Nutrition

Plant Sensory Systems, signals, and Responses

Plant Reproduction

Animal Form and Function

Water and Electrolyte Balance in Animals

Animal Nutrition

Gas Exchange and Circulation

Electrical Signals in Animals

Animal Sensory Systems and Movement

Chemical Signals in Animals

Animal Reproduction

The Immune System in Animals

An Introduction to Ecology

Behavioral Ecology

Population Ecology

Community Ecology

Ecosystems

Biodiversity and Conservation Biology

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