Question 1

Not all intercellular signals require transduction.Which one of the following signals would be processed without transduction?

Accepted Answer

A) a lipid-soluble signal 
B) a signal that is weakly bound to a nucleotide 
C) a signal that binds to a receptor in the cell membrane 
D) a signal that binds to the ECM 
A) a lipid-soluble signal 
B) a signal that is weakly bound to a nucleotide 
C) a signal that binds to a receptor in the cell membrane 
D) a signal that binds to the ECM

Question 2

Hormones are chemical substances produced in one organ that are released into the bloodstream and affect the function of a target organ.For the target organ to respond to a particular hormone,it must _____.

Accepted Answer

A) modify its plasma membrane to alter hormone entering the cytoplasm 
B) be from the same cell type as the organ that produced the hormone 
C) experiencing an imbalance that disrupts its normal function 
D) have receptors that recognize and bind the hormone molecule 
A) modify its plasma membrane to alter hormone entering the cytoplasm 
B) be from the same cell type as the organ that produced the hormone 
C) experiencing an imbalance that disrupts its normal function 
D) have receptors that recognize and bind the hormone molecule

Question 3

The receptors for steroid hormones are located inside the cell,instead of on the membrane surface like most other signal receptors.Why is this not a problem for steroids?

Accepted Answer

A) because the receptors can be readily stimulated to exit and relocate on the membrane surface 
B) because receptors located inside cells are less susceptible to blockage by inhibitors located on or near the cell surface,so it serves as a protective mechanism 
C) because steroid hormones are lipid soluble so can readily diffuse through the lipid bilayer of the cell membrane 
D) because the receptors are repressible,meaning they are actively altering cell function unless the target hormone is present 
A) because the receptors can be readily stimulated to exit and relocate on the membrane surface 
B) because receptors located inside cells are less susceptible to blockage by inhibitors located on or near the cell surface,so it serves as a protective mechanism 
C) because steroid hormones are lipid soluble so can readily diffuse through the lipid bilayer of the cell membrane 
D) because the receptors are repressible,meaning they are actively altering cell function unless the target hormone is present

Question 4

Which of the following statements about quorum sensing is not accurate?

Accepted Answer

A) Quorum sensing is cell-cell communication in prokaryotes. 
B) Quorum sensing is species specific. 
C) Quorum sensing may result in biofilm formation. 
D) Quorum sensing is particularly well studied because of its importance in understanding interactions between prokaryotes and eukaryotes. 
A) Quorum sensing is cell-cell communication in prokaryotes. 
B) Quorum sensing is species specific. 
C) Quorum sensing may result in biofilm formation. 
D) Quorum sensing is particularly well studied because of its importance in understanding interactions between prokaryotes and eukaryotes.

Question 5

Integrins are integral membrane proteins.They are often attached to _____.

Accepted Answer

A) the membranes of intracellular organelles 
B) cytoskeletal proteins and proteins in the extracellular matrix 
C) the outside of the plasma membrane 
D) glycogen molecules and other types of cellular inclusions 
A) the membranes of intracellular organelles 
B) cytoskeletal proteins and proteins in the extracellular matrix 
C) the outside of the plasma membrane 
D) glycogen molecules and other types of cellular inclusions

Question 6

Which of the following statements is false?

Accepted Answer

A) When plant cells are growing,they release expansins,which are enzymes that can expand the primary cell wall. 
B) The secondary cell wall often contains structural components,like lignin,that form a relatively rigid and complex network within the cell wall. 
C) A plant cell continues growing after the secondary cell wall forms but stops growing with the formation of the tertiary cell wall. 
D) Pectin is a component of the cell wall that attracts and holds water. 
A) When plant cells are growing,they release expansins,which are enzymes that can expand the primary cell wall. 
B) The secondary cell wall often contains structural components,like lignin,that form a relatively rigid and complex network within the cell wall. 
C) A plant cell continues growing after the secondary cell wall forms but stops growing with the formation of the tertiary cell wall. 
D) Pectin is a component of the cell wall that attracts and holds water.

Question 7

What is the function of the middle lamella in plant cells?

Accepted Answer

A) It allows adjacent cells to adhere to one another. 
B) It prevents dehydration of adjacent cells. 
C) It maintains the plant's circulatory system. 
D) It allows for gas and nutrient exchange among adjacent cells. 
A) It allows adjacent cells to adhere to one another. 
B) It prevents dehydration of adjacent cells. 
C) It maintains the plant's circulatory system. 
D) It allows for gas and nutrient exchange among adjacent cells.

Exam 8: Cell-Cell Interactions

Not all intercellular signals require transduction.Which one of the following signals would be processed without transduction?

Hormones are chemical substances produced in one organ that are released into the bloodstream and affect the function of a target organ.For the target organ to respond to a particular hormone,it must _____.

The receptors for steroid hormones are located inside the cell,instead of on the membrane surface like most other signal receptors.Why is this not a problem for steroids?

Which of the following statements about quorum sensing is not accurate?

Integrins are integral membrane proteins.They are often attached to _____.

Which of the following statements is false?

What is the function of the middle lamella in plant cells?

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

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

Principles of Development

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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