Question

An organ is a structure made of two or more tissues performing a common function. Which of the four tissue types are present in the wall of the digestive tract? a. epithelium b. connective tissue c. nervous tissue d. muscle tissue e. All of these are correct.

Short answer

The wall of the digestive tract contains all four tissue types working together to perform the common function of digestion: epithelium (lining and secreting mucus), connective tissue (support and containing blood vessels), nervous tissue (controlling contractions), and muscle tissue (propelling food forward). Thus, the correct answer is e. All of these are correct.

Step-by-step solution

Understand the function of the digestive tract wall

The main function of the digestive tract is to digest food by breaking it down into its essential components and releasing nutrients for the body. The wall of the digestive tract plays an important role in this process by providing support, protection, and facilitating the movement of food through the tract.

Define the four tissue types

There are four main types of tissues in the human body with different functions. a. Epithelium: This tissue type consists of closely-packed cells that form the lining of internal and external surfaces of the body. It protects the body from microbes, injury, and fluid loss. b. Connective tissue: This type of tissue provides support, protects the organs, stores energy, and transports nutrients and waste products. It includes various types of cells, fibers, and an extracellular matrix. c. Nervous tissue: It comprises nerve cells (neurons) and supporting cells (glial cells). Its primary function is to transmit and receive signals, processing information, and controlling the body's movements and functions. d. Muscle tissue: This tissue type is responsible for generating force and movement. There are three types of muscle tissues: skeletal, cardiac, and smooth.

Identify the tissue types in the digestive tract wall

The wall of the digestive tract consists of these four tissue types working together to perform the common function of digestion: a. Epithelium: The innermost layer of the digestive tract is the mucosa, which is made up of epithelial cells. These cells secrete mucus and digestive enzymes, absorb nutrients, and provide protection. b. Connective tissue: The submucosa, which lays beneath the mucosa, is made up of connective tissue. It provides support to the digestive tract and contains blood vessels and nerves. c. Nervous tissue: The nervous tissue is present in the enteric nervous system, which regulates the digestive processes and controls the smooth muscle contractions for moving food through the tract. d. Muscle tissue: The wall of the digestive tract contains layers of smooth muscle tissue, which contract to mix and propel the food forward efficiently. Therefore, the correct answer is: e. All of these are correct.