Tiêu đề Ex- 1. Digestion and absorption (Q-A-Sol).docx.pdf ✅

8 DIGESTION AND ABSORPTION EXERCISE – 1: Basic Objective Questions Digestive System 1. Alimentary Canal 1. The anterior and posterior opening of alimentary canal is (a) Mouth and anus (b) Buccal cavity and rectum (c) Epiglottis and anus (d) Food pipe and large intestine. Ans. (a) Sol. The alimentary canal is a long tube through which the food passes. The anterior opening of the alimentary canal is mouth. Its posterior end is anus. 2. The tongue is (a) Freely movable and cartilaginous (b) Immovable and tough (c) freely movable and muscular (d) slightly movable and fatty Ans. (c) Sol. The tongue is a freely movable and muscular organ. It is attached to the floor of the oral cavity by the frenulum. 3. Recognize the figure and find out the correct matching. (a) a-incisor, b-canine, c-molars, d-premolars (b) a-incisor, b-canine, d-molars, c-premolars (c) d-incisor, c-canine, b-molars, a-premolars (d) d-incisor, c-canine, a-molars, b-premolars Ans. (d) Sol. First, eight teeth in front of the mouth are incisors which function in biting food, next to it is the canine which functions in tearing food. Premolars and molars are large teeth present deep inside the mouth for crushing and masticating food. 4. Tongue is attached to the floor of the oral cavity by ____ (a) Papillae (b) Frenulum (c) Enamel (d) Fundus Ans. (b) Sol. The frenulum is a connective tissue membrane that connects the upper surface of the mouth to the lower surface. The tongue is attached to the floor of the oral cavity with the help of the frenulum. 5. The taste buds are present on (a) Some papillae of the tongue (b) All papillae of the tongue (c) Salivary glands (d) Frenulum of the tongue Ans. (a) Sol. The tongue has small projections on its surface. These are called papillae. Some of these papillae can detect sour, sweet, bitter and salty taste. 6. Number of canines in upper half jaw is (a) 4 (b) 3
9 DIGESTION AND ABSORPTION (c) 2 (d) 1 Ans. (d) Sol. The number of canine teeth in the upper half jaw is one. The total number of canine teeth in an adult human is four. It functions in the tearing of food substances. It is present next to incisors, before premolars. 7. Total number of canines in a permanent dental set of humans is (a) 4 (b) 6 (c) 2 (d) 12 Ans. (a) Sol. The number of canine teeth in a permanent dental set of humans is 4. Canine is present next to the incisor in the one-half jaw-line. In our dental set , and 1 in this formula represents the position and number of canines in each half jaw. 8. Dental formula of adult man is: (a) (b) (c) (d) Ans. (a) Sol. The dental formula in an adult humanism . Here, in the upper half jaw 2 represents the two incisors present in front of the mouth next to which is a single sharp tooth called canine. After canine is broad premolars and molars which are 2 and 3 in number respectively. 9. The roof of the buccal cavity forms: (a) Palate (b) Gullet (c) Hyoid (d) Glottis Ans. (a) Sol. The roof of the buccal cavity or mouth is called the palate. It separates the nasal and oral cavity acting as a mechanical barrier between the nose and mouth. 10. Type of teeth present in humans is (a) Diphyodont and homodont (b) Monophyodont and thecodont (c) Monophyodont and homodont (d) Diphyodont and heterodont Ans. (d) Sol. Humans have the diphyodont and heterodont type of dentition. Diphyodont is the condition in which two sets of teeth occur successively one after the other in a lifetime. Humans have different types of teeth located on the socket of the jawbone for different purposes, a condition called heterodont. 11. The hardest substance in the vertebrate body is: (a) Keratin (b) Dentine (c) Enamel (d) Chondrin Ans. (c) Sol. Enamel is the hardest substance in the vertebrate body. It is made up of hard inorganic substances such as calcium phosphate arranged together to form hydroxyapatite crystals. This crystal formation provides rigidity to the bones and teeth. 12. Wisdom tooth in human is: (a) 3 rd molar and 4 in number (b) 3 rd molar and 2 in number (c) 2 nd molar and 4 in number (d) 2 nd molar and 2 in number Ans. (a) Sol. There are a total of four wisdom teeth, two on top and two on the bottom. These are 3 rd molar teeth present in the innermost portion of the jaw line. Most teeth erupt before the age of 18 years, but wisdom teeth emerge when a person is around 19-20 years old. 13. Dental formula shows (a) Structure of teeth (b) Monophyodont or diphyodont condition (c) Number and type of teeth in both jaws (d) Number and type of teeth in one-half of both jaws Ans. (d) Sol. The dental formula shows the number and type of teeth in one-half of both the jaws. The fractional
10 DIGESTION AND ABSORPTION representation of the upper and lower lines represents the number of teeth in upper and lower jawline sockets. The dental formula of an adult human is . 14. The common passage for food and air is (a) Pharynx (b) Buccal cavity (c) Oesophagus (d) Nasopharynx Ans. (a) Sol. Pharynx serves as common passage for both food and air. From pharynx, the food enters the oesophagus and air enters the trachea. 15. The structure which prevents the entry of food into respiratory tract is (a) Glottis (b) Pharynx (c) Epiglottis (d) Larynx Ans. (c) Sol. Epiglottis is a flap-like structure located at the entry of larynx. Its main function is to prevent food items from entering the trachea or the airway. 16. Opening of the trachea or wind-pipe is called (a) Glottis (b) Epiglottis (c) Larynx (d) Pharynx Ans. (a) Sol. Glottis consists of two thick folds of mucous membrane called vestibular folds and true vocal cord having space in between these two folds. The vestibular fold is also known as a false vocal cord (one of the folded pair sections of the mucous membrane). A true vocal cord is a membranous fold attached to the thyroid and larynx. 17. The epiglottis is made up of (a) Bones (b) Muscles (c) Cartilage (d) Both (a) and (b) Ans. (c) Sol. The epiglottis is made up of fibrocartilage. It is yellowish in colour and covers the opening of the wind pipe (trachea) during swallowing of food. 18. The stomach is located in the (a) Upper left portion of thoracic cavity (b) Lower left portion of thoracic cavity (c) Upper left portion of abdominal cavity (d) Upper right portion of abdominal cavity Ans. (c) Sol. The stomach is located in the upper-left portion of the abdominal cavity. It has 4 parts- cardiac (the place where the oesophagus connects to the stomach), fundus, body (main central region) and pyloric (connects the stomach to the duodenum). 19. The opening of oesophagus into the stomach is regulated by (a) Pyloric sphincter (b) Gastro-oesophageal sphincter (c) Epiglottis (d) Uvula Ans. (b) Sol. The opening of oesophagus into the stomach is regulated by gastro-oesophageal sphincter. It is a muscular flap which prevents backward movement of food bolus from stomach into the oesophagus. 20. The irregular folds formed by mucosa layer of the stomach wall are called (a) Rugae (b) Villi (c) Papillae (d) Gyri Ans. (a) Sol. The wall of the alimentary canal in the stomach region is slightly different from other regions. In stomach the mucosa forms irregular folds called rugae. They increase the surface area and help in proper digestion of food. 21. The parts of the small intestine in the correct sequence are: (a) Duodenum, ileum, jejunum (b) Colon, caecum, jejunum (c) Duodenum, colon, ileum (d) Duodenum, jejunum, ileum Ans. (d) Sol. The small intestine of humans consists of three parts, first being the duodenum a C-shaped structure. The jejunum is the next which connects to the ileum that is the last part of the small intestine. 22. The small intestine opens into large intestine through (a) Jejunum (b) Duodenum (c) Ileum (d) Ischium
11 DIGESTION AND ABSORPTION Ans. (c) Sol. The small intestine opens into large intestine through ileum. It connects to the caecum (first part of the large intestine). 23. The colon is divided into four parts that are (a) Upper, middle, lower, bottom (b) Central, lateral, ventral and medial (c) Proximal, middle, lateral and distal (d) Ascending, transverse, descending and sigmoid Ans. (d) Sol. The large intestine can be divided into - caecum, colon and rectum. The colon can be further divided into ascending colon, transverse colon, descending colon and sigmoid colon. Caecum continues as ascending colon which further continues as transverse, then descending and sigmoid colon and finally terminating into the rectum. 24. Vermiform appendix is part of (a) Reproductive system (b) Alimentary canal (c) Vascular system (d) Nervous system Ans. (b) Sol. The vermiform appendix is part of the alimentary canal. The vermiform appendix is also known as the caecal appendix. It is a finger-like, blind-ended tubular projection connected to the caecum. Therefore, it is a part of the large intestine. It is a vestigial organ which is closed at one end and attached to caecum at the other end. It can get infected and lead to a disease known as appendicitis. 25. A small blind sac present in the large intestine is known as (a) Caecum (b) Ascending colon (c) Descending colon (d) Transverse colon Ans. (a) Sol. A small blind sac present in the large intestine is known as caecum. It harbors some symbiotic bacteria. 26. The vestigial organ present in large intestine of humans is (a) Caecum (b) Vermiform appendix (c) Some ascending part of colon (d) Transverse colon Ans. (b) Sol. Vermiform appendix is a narrow, finger like, tubular projection which arise from caecum. It is a vestigial organ in human beings. But, in herbivores it is well developed to digest cellulose through symbiotic bacteria. 27. The outermost layer of the wall of alimentary canal is made up of (a) Smooth muscles with some connective tissue (b) Thin mesothelium with some connective tissue (c) Loose connective tissues containing nerves, blood and lymph vessels (d) Both a and b Ans. (b) Sol. The outermost layer of the gastrointestinal wall is called as serosa. It is made up of thin mesothelium containing some connective tissues. Serosa plays an important role in lubrication. 28. The submucosal layer is made up of (a) Smooth muscles with some connective tissue (b) Thin mesothelium with some connective tissue (c) Loose connective tissues containing nerves, blood and lymph vessels (d) Both (a) and (b) Ans. (c) Sol. The submucosal layer is made up of loose connective tissues, blood vessels and lymphatics. It lies inner to the mucosa and separates it from muscularis layer. It also plays an important role in supporting mucosa. 29. Fill in the blanks: 1. ___a___ provides energy and organic materials for growth and repair of tissues. 2. Each tooth is embedded in a socket of jaw bone. This type of attachment is called ____b___ 3. Majority of mammals including human being form two sets of teeth during their life. This type of dentition is called ___c___. (a) a-food, b-thecodont, c-diphyodont (b) a-vitamins, b-diphyodont, c-thecodont