Cephalization and bilateral symmetry of a body contribute to the evolutionary development of invertebrates. Cephalization is the formation of head at the frontal region of the body of organisms. The head consists of brain having ganglia and nerve cords. Ganglia is a group of nerve cells with specialized functions. The enlargement and clustering of ganglia lead to the development of brain.

Question

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Answer 1

Question

Chapter 40, Problem 1TYK

Summary Introduction

Introduction:

Cephalization and bilateral symmetry of a body contribute to the evolutionary development of invertebrates. Cephalization is the formation of head at the frontal region of the body of organisms. The head consists of brain having ganglia and nerve cords. Ganglia is a group of nerve cells with specialized functions. The enlargement and clustering of ganglia lead to the development of brain.

Expert Solution & Answer

Answer to Problem 1TYK

Correct answer:

Cephalopods.

Explanation of Solution

Justification/explanation for the correct answer:

Option (d) is cephalopods. Mollusks have neuron clusters and major nerves. Different mollusks have different degree of cephalization. The cephalopods groups of mollusks have cluster of ganglia, which gets fused into a complex lobe. Hence, option (d) is correct.

Explanation for the incorrect answer:

Option (a) is vertebrates. The cephalization occurs in invertebrates and the vertebrates are evolved from invertebrates. So, it is an incorrect option.

Option (b) is annelids. Annelids have a cerebral ganglion at the front of their body and a ventral nerve cord, which works as brain, whereas a true brain has a cluster of ganglia and two nerve cords. So, it is an incorrect option.

Option (c) is flatworms. The formation of ganglia, that is, clustering of nerve cells, first occurred in flatworms, which is a simple invertebrate and the enlargement of ganglia occurred later in complex invertebrates. So, it is an incorrect option.

Option (e) is mammals. Mammals come under vertebrate group, which have developed from invertebrates, and head formation occurred in invertebrates. So, it is an incorrect option.

Hence, options (a), (b), (c), and (e) are incorrect.

Conclusion

Therefore, it can be concluded that the process of cephalization (frontal head formation) was first seen in cephalopods.

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Students have asked these similar questions

Which of the following physiological systems has undergone selection in cockroaches in response to poison traps placed by humans? a. Tactile sensory neurons to sense human movement b. Visual systems to detect bait traps c. Digestion of glucose in the stomach d. Taste and sensory neurons

What do the sensory systems of annelids, mollusks, arthropods, and vertebrates have in common?a. They all use the same stimuli for taste.b. They all use neurons to detect vibration.c. They all have image-forming eyes that evolved independently.d. They all use chemoreceptors in their skin to detect food.

The most intelligent invertebrates are probably thea. annelids.b. arthropods.c. cephalopods.d. None of these can be regarded as intelligent.

Answer 2

Question

Chapter 40, Problem 1TYK

Summary Introduction

Introduction:

Cephalization and bilateral symmetry of a body contribute to the evolutionary development of invertebrates. Cephalization is the formation of head at the frontal region of the body of organisms. The head consists of brain having ganglia and nerve cords. Ganglia is a group of nerve cells with specialized functions. The enlargement and clustering of ganglia lead to the development of brain.

Expert Solution & Answer

Answer to Problem 1TYK

Correct answer:

Cephalopods.

Explanation of Solution

Justification/explanation for the correct answer:

Option (d) is cephalopods. Mollusks have neuron clusters and major nerves. Different mollusks have different degree of cephalization. The cephalopods groups of mollusks have cluster of ganglia, which gets fused into a complex lobe. Hence, option (d) is correct.

Explanation for the incorrect answer:

Option (a) is vertebrates. The cephalization occurs in invertebrates and the vertebrates are evolved from invertebrates. So, it is an incorrect option.

Option (b) is annelids. Annelids have a cerebral ganglion at the front of their body and a ventral nerve cord, which works as brain, whereas a true brain has a cluster of ganglia and two nerve cords. So, it is an incorrect option.

Option (c) is flatworms. The formation of ganglia, that is, clustering of nerve cells, first occurred in flatworms, which is a simple invertebrate and the enlargement of ganglia occurred later in complex invertebrates. So, it is an incorrect option.

Option (e) is mammals. Mammals come under vertebrate group, which have developed from invertebrates, and head formation occurred in invertebrates. So, it is an incorrect option.

Hence, options (a), (b), (c), and (e) are incorrect.

Conclusion

Therefore, it can be concluded that the process of cephalization (frontal head formation) was first seen in cephalopods.

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Answer 3

Question

Chapter 40, Problem 1TYK

Summary Introduction

Introduction:

Cephalization and bilateral symmetry of a body contribute to the evolutionary development of invertebrates. Cephalization is the formation of head at the frontal region of the body of organisms. The head consists of brain having ganglia and nerve cords. Ganglia is a group of nerve cells with specialized functions. The enlargement and clustering of ganglia lead to the development of brain.

Expert Solution & Answer

Answer to Problem 1TYK

Correct answer:

Cephalopods.

Explanation of Solution

Justification/explanation for the correct answer:

Option (d) is cephalopods. Mollusks have neuron clusters and major nerves. Different mollusks have different degree of cephalization. The cephalopods groups of mollusks have cluster of ganglia, which gets fused into a complex lobe. Hence, option (d) is correct.

Explanation for the incorrect answer:

Option (a) is vertebrates. The cephalization occurs in invertebrates and the vertebrates are evolved from invertebrates. So, it is an incorrect option.

Option (b) is annelids. Annelids have a cerebral ganglion at the front of their body and a ventral nerve cord, which works as brain, whereas a true brain has a cluster of ganglia and two nerve cords. So, it is an incorrect option.

Option (c) is flatworms. The formation of ganglia, that is, clustering of nerve cells, first occurred in flatworms, which is a simple invertebrate and the enlargement of ganglia occurred later in complex invertebrates. So, it is an incorrect option.

Option (e) is mammals. Mammals come under vertebrate group, which have developed from invertebrates, and head formation occurred in invertebrates. So, it is an incorrect option.

Hence, options (a), (b), (c), and (e) are incorrect.

Conclusion

Therefore, it can be concluded that the process of cephalization (frontal head formation) was first seen in cephalopods.

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Answer 4

Question

Chapter 40, Problem 1TYK

Summary Introduction

Introduction:

Cephalization and bilateral symmetry of a body contribute to the evolutionary development of invertebrates. Cephalization is the formation of head at the frontal region of the body of organisms. The head consists of brain having ganglia and nerve cords. Ganglia is a group of nerve cells with specialized functions. The enlargement and clustering of ganglia lead to the development of brain.

Expert Solution & Answer

Answer to Problem 1TYK

Correct answer:

Cephalopods.

Explanation of Solution

Justification/explanation for the correct answer:

Option (d) is cephalopods. Mollusks have neuron clusters and major nerves. Different mollusks have different degree of cephalization. The cephalopods groups of mollusks have cluster of ganglia, which gets fused into a complex lobe. Hence, option (d) is correct.

Explanation for the incorrect answer:

Option (a) is vertebrates. The cephalization occurs in invertebrates and the vertebrates are evolved from invertebrates. So, it is an incorrect option.

Option (b) is annelids. Annelids have a cerebral ganglion at the front of their body and a ventral nerve cord, which works as brain, whereas a true brain has a cluster of ganglia and two nerve cords. So, it is an incorrect option.

Option (c) is flatworms. The formation of ganglia, that is, clustering of nerve cells, first occurred in flatworms, which is a simple invertebrate and the enlargement of ganglia occurred later in complex invertebrates. So, it is an incorrect option.

Option (e) is mammals. Mammals come under vertebrate group, which have developed from invertebrates, and head formation occurred in invertebrates. So, it is an incorrect option.

Hence, options (a), (b), (c), and (e) are incorrect.

Conclusion

Therefore, it can be concluded that the process of cephalization (frontal head formation) was first seen in cephalopods.

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Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 5

Chapter 40, Problem 1TYK

Summary Introduction

Introduction:

Cephalization and bilateral symmetry of a body contribute to the evolutionary development of invertebrates. Cephalization is the formation of head at the frontal region of the body of organisms. The head consists of brain having ganglia and nerve cords. Ganglia is a group of nerve cells with specialized functions. The enlargement and clustering of ganglia lead to the development of brain.

Expert Solution & Answer

Answer to Problem 1TYK

Correct answer:

Cephalopods.

Explanation of Solution

Justification/explanation for the correct answer:

Option (d) is cephalopods. Mollusks have neuron clusters and major nerves. Different mollusks have different degree of cephalization. The cephalopods groups of mollusks have cluster of ganglia, which gets fused into a complex lobe. Hence, option (d) is correct.

Explanation for the incorrect answer:

Option (a) is vertebrates. The cephalization occurs in invertebrates and the vertebrates are evolved from invertebrates. So, it is an incorrect option.

Option (b) is annelids. Annelids have a cerebral ganglion at the front of their body and a ventral nerve cord, which works as brain, whereas a true brain has a cluster of ganglia and two nerve cords. So, it is an incorrect option.

Option (c) is flatworms. The formation of ganglia, that is, clustering of nerve cells, first occurred in flatworms, which is a simple invertebrate and the enlargement of ganglia occurred later in complex invertebrates. So, it is an incorrect option.

Option (e) is mammals. Mammals come under vertebrate group, which have developed from invertebrates, and head formation occurred in invertebrates. So, it is an incorrect option.

Hence, options (a), (b), (c), and (e) are incorrect.

Conclusion

Therefore, it can be concluded that the process of cephalization (frontal head formation) was first seen in cephalopods.

Answer 6

Chapter 40, Problem 1TYK

Summary Introduction

Introduction:

Cephalization and bilateral symmetry of a body contribute to the evolutionary development of invertebrates. Cephalization is the formation of head at the frontal region of the body of organisms. The head consists of brain having ganglia and nerve cords. Ganglia is a group of nerve cells with specialized functions. The enlargement and clustering of ganglia lead to the development of brain.

Expert Solution & Answer

Answer to Problem 1TYK

Correct answer:

Cephalopods.

Explanation of Solution

Justification/explanation for the correct answer:

Option (d) is cephalopods. Mollusks have neuron clusters and major nerves. Different mollusks have different degree of cephalization. The cephalopods groups of mollusks have cluster of ganglia, which gets fused into a complex lobe. Hence, option (d) is correct.

Explanation for the incorrect answer:

Option (a) is vertebrates. The cephalization occurs in invertebrates and the vertebrates are evolved from invertebrates. So, it is an incorrect option.

Option (b) is annelids. Annelids have a cerebral ganglion at the front of their body and a ventral nerve cord, which works as brain, whereas a true brain has a cluster of ganglia and two nerve cords. So, it is an incorrect option.

Option (c) is flatworms. The formation of ganglia, that is, clustering of nerve cells, first occurred in flatworms, which is a simple invertebrate and the enlargement of ganglia occurred later in complex invertebrates. So, it is an incorrect option.

Option (e) is mammals. Mammals come under vertebrate group, which have developed from invertebrates, and head formation occurred in invertebrates. So, it is an incorrect option.

Hence, options (a), (b), (c), and (e) are incorrect.

Conclusion

Therefore, it can be concluded that the process of cephalization (frontal head formation) was first seen in cephalopods.

Answer 7

Chapter 40, Problem 1TYK

Summary Introduction

Introduction:

Cephalization and bilateral symmetry of a body contribute to the evolutionary development of invertebrates. Cephalization is the formation of head at the frontal region of the body of organisms. The head consists of brain having ganglia and nerve cords. Ganglia is a group of nerve cells with specialized functions. The enlargement and clustering of ganglia lead to the development of brain.

Answer 8

Expert Solution & Answer

Answer to Problem 1TYK

Correct answer:

Cephalopods.

Answer 9

Expert Solution & Answer

Answer 10

Expert Solution & Answer

Answer 11

Explanation of Solution

Justification/explanation for the correct answer:

Option (d) is cephalopods. Mollusks have neuron clusters and major nerves. Different mollusks have different degree of cephalization. The cephalopods groups of mollusks have cluster of ganglia, which gets fused into a complex lobe. Hence, option (d) is correct.

Explanation for the incorrect answer:

Option (a) is vertebrates. The cephalization occurs in invertebrates and the vertebrates are evolved from invertebrates. So, it is an incorrect option.

Option (b) is annelids. Annelids have a cerebral ganglion at the front of their body and a ventral nerve cord, which works as brain, whereas a true brain has a cluster of ganglia and two nerve cords. So, it is an incorrect option.

Option (c) is flatworms. The formation of ganglia, that is, clustering of nerve cells, first occurred in flatworms, which is a simple invertebrate and the enlargement of ganglia occurred later in complex invertebrates. So, it is an incorrect option.

Option (e) is mammals. Mammals come under vertebrate group, which have developed from invertebrates, and head formation occurred in invertebrates. So, it is an incorrect option.

Hence, options (a), (b), (c), and (e) are incorrect.