CBSE Questions for Class 11 Medical Biology Digestion And Absorption Quiz 11 - MCQExams.com

• Canines are dagger-shaped and lie behind the incisors. These are used for ripping and tearing. 
• Incisors are sharp, pointed, chisel-shaped and used for cutting.
• Premolar and molars are used for grinding food. 
• so, the correct option is A.

• The cartilaginous structure called epiglottis is a flap of elastic gristle tissue lined with mucosa, hooked up to the entrance of the vocal organ. It barriers the entry of food into the larynx and routes it to the esophagus.  
• One may instantly start coughing while swallowing food because of the improper movement of the epiglottis. Hence, improper movement of epiglottis leads to cough while swallowing food.

$$\textbf{Correct answer: C}$$ 

$$\textbf{Option (A):}$$ 

$$\bullet$$ $$Bacillus$$ $$pertussis$$ causes the bacterial disease pertussis in patients and not any diarrhoeal disease.

$$\textbf{Option (B):}$$ 

$$\bullet$$ $$Clostridium$$ $$tetani$$ is a soil bacteria that is the agent responsible for causing tetanus.

$$\textbf{Option (C):}$$ 

$$\bullet$$ All the pathogens including $$Escherichia$$ $$coli$$, $$Giardia$$, $$Shigella$$, $$Campylobacter$$ and $$Salmonella$$ are causative agents of diarrhoeal diseases.

$$\textbf{Option (D):}$$ 

$$\bullet$$ $$Neisseria$$ and $$Treponema$$ are sexually transmitted diseases and they do not cause diarrhoea.

Hence, the correct answer is option (C).

$$\textbf{Correct answer: D}$$ 

$$\textbf{Option (A):}$$ 

$$\bullet$$ Changes in body temperature can occur due to the presence of specific hormones.

$$\bullet$$ Due to the excessive rise in thyroid secretion, the body temperature of the individual tends to rise due to high metabolic activity. 

$$\bullet$$ The higher metabolic activity induces food intake in the individual. It also significantly affects the levels of protein in the bloodstream.

$$\textbf{Option (B):}$$ 

$$\bullet$$ Psychological factors can influence the feelings of hunger in humans. There is a basic requirement of nutrients for the generation of energy in the system. 

$$\bullet$$ The feeling of hunger is controlled by the central nervous system and it also shows the feeling of appetite and satiety.

$$\textbf{Option (C):}$$ 

$$\bullet$$ Carbohydrate that people consume turns into blood glucose.

$$\bullet$$ Due to the higher level of blood glucose which is digested and absorbed by the system, the requirements of nutrients decreases, causing less food intake.

$$\textbf{Option (D):}$$ 

$$\bullet$$ All the given factors have a direct influence in regulating the total food intake of any individual.

Hence, the correct answer is option (D).

• The digestion process depends upon hydrolysis to provide the biochemical reactions that break down food.
•  The digestive tract secretes enzymes, such as proteases, carbohydrases, nucleases and lipases that, along with water, catalyze the hydrolysis that releases various nutrients. Hence, the Digestion of food occurs as a result of hydrolysis.

1. The stomach produces gastrin, hydrochloric acid and pepsinogen.
2. G-cells in the stomach releases gastrin in response to distension of the antrum. This, in turn, causes an increase in the secretion of HCl from the parietal cells or oxyntic cells, which kills or inhibits bacteria and provides the acidic pH for the proteases to work and pepsinogen is released from chief cells in the stomach called zymogenic cells or peptic cells. 
3. Pepsinogen, inactive form of the enzyme in presence of hydrochloric acid activates into the active form, pepsin. Pepsin breaks down proteins into polypeptides. Hence, sodium hydrogen carbonate is not produced in the stomach.
   

$$\textbf{Correct answer: D}$$ 

$$\textbf{Option (A):}$$ 

$$\bullet$$ Pleurodont teeth have long roots with weak attachments to the mandible. There is no socket for the teeth to be placed on the jaw. 

$$\bullet$$ Monophyodont teeth mean the presence of only one set of teeth for the entire lifetime.

$$\bullet$$ Homodont means the presence of a single type of teeth. 

$$\bullet$$ None of these characters are observed in human dentition. 

$$\textbf{Option (B):}$$ 

$$\bullet$$ The thecodont teeth are the type of teeth containing the base of the tooth which is completely immersed inside the socket present on the jawbone. 

$$\bullet$$ Diphyodont teeth are the presence of two sets of teeth throughout the entire lifecycle. 

$$\bullet$$ Human dentition shows the thecodont and diphyodont character. But the homodont character is not observed.

$$\textbf{Option (C):}$$ 

$$\bullet$$ Heterodont teeth mean the presence of different types of teeth with different functions. 

$$\bullet$$ Human dentition does not have the pleurodont character, but it is both diphyodont and heterodont.

$$\textbf{Option (D):}$$ 

$$\bullet$$ Human dentition is thecodont because of the presence of sockets in the jawbone where the teeth are embedded. 

$$\bullet$$ Human dentition shows a diphyodont character because of the presence of two sets of teeth throughout the life cycle. The first set is called the deciduous teeth and the second set is the permanent teeth. 

$$\bullet$$ Human dentition shows heterodont character because of the presence of four types of teeth which are incisors, canine, premolars and molars. 

Hence, the correct answer is option (D).

• An intestinal gland is additionally a sepulture of Lieberkuhn and therefore the intestinal crypt is a gland found in between villi within the intestinal epithelium lining of the tiny intestine organ and huge intestine. 
• Lieberkühn glands, occupying the mucosa membrane, secrete digestive enzymes, give outlet ports for Brunner glands, and manufacture cells that replace surface-membrane cells shed from the guidelines of villi. Hence, Crypts of lieberkuhn are found in the small intestine and secret digestive enzymes.