Alimentary System

Which organs are part of the alimentary canal in the human digestive system?

Answer Details

The organs that are part of the alimentary canal in the human digestive system are the **esophagus, stomach, pancreas, and small intestine**. **Esophagus**: It is a muscular tube that connects the mouth to the stomach. Its role is to transport food from the mouth to the stomach through a process called peristalsis, which is the contraction and relaxation of the muscles in the esophagus. **Stomach**: The stomach is a J-shaped organ located below your diaphragm in the upper-left side of your abdomen. It is an important part of the digestive system because it breaks down food into a liquid mixture called chyme. The stomach has strong muscles that churn and mix the food with digestive juices that contain acids and enzymes. **Pancreas**: The pancreas is a long, flat gland located behind the stomach. It has both endocrine and exocrine functions. In terms of digestion, the pancreas releases digestive enzymes into the small intestine to help break down carbohydrates, fats, and proteins. **Small Intestine**: The small intestine is a long, coiled tube that is the major site of digestion and absorption of nutrients. It is divided into three sections: the duodenum, jejunum, and ileum. The lining of the small intestine has tiny finger-like projections called villi, which increase its surface area for efficient absorption of nutrients into the bloodstream. It's important to note that while the salivary glands, tongue, pharynx, large intestine, appendix, and rectum are all important parts of the digestive system, they are not part of the alimentary canal. The salivary glands produce saliva, the tongue helps with chewing and swallowing, and the pharynx is the pathway for food and air. The large intestine, appendix, and rectum are mainly involved in the absorption of water, electrolytes, and the elimination of solid waste. To summarize, the organs that are part of the alimentary canal in the human digestive system are the **esophagus, stomach, pancreas, and small intestine**. These organs work together to break down food, absorb nutrients, and eliminate waste.

5.(a) State three differences between the alimentary canals of earthworm and cockroach.

(i) State three similarities between the alimentary canals of earthworm and cockroach.

(b) The diagram below is an illustration of a biological cycle.

 Study it and answer questions 5(b)i) to 5(b)(iii)

[i]Name the biological cycle (i) Explain briefly three roles played by plants and animals in the cycle (ii) Name the process that occur in X, Y and Z.

 c. complete the table below.

(d)i) What is decay of organic matter

(i) Name two groups of organisms that cause decay of organic matter.

(i) State one other factor that causes decay.

(iv) Name the biological cycle that involves decay.

(e) Explain briefly the mode of nutrition in carnivorous plants.

Answer Details

a) Differences between the alimentary canals of earthworm and cockroach: 1. Earthworm: The alimentary canal of an earthworm is a straight tube running from the mouth to the anus, consisting of the pharynx, esophagus, crop, gizzard, intestine, and anus. Cockroach: The alimentary canal of a cockroach is a long, coiled tube consisting of the mouth, esophagus, crop, gizzard, stomach, gastric ceca, Malpighian tubules, and rectum. 2. Earthworm: Earthworms are herbivorous, and their alimentary canal is specialized for the digestion of plant matter, including cellulose. Cockroach: Cockroaches are omnivorous, and their alimentary canal is adapted for the digestion of both plant and animal matter. 3. Earthworm: Earthworms lack specialized structures for grinding food. Instead, they rely on muscular contractions of the gizzard for mechanical digestion. Cockroach: Cockroaches have a specialized structure called the gizzard, which helps in the mechanical breakdown of food. Similarities between the alimentary canals of earthworm and cockroach: 1. Both earthworms and cockroaches have a similar arrangement of digestive structures, including the crop and gizzard, which aid in food storage and mechanical digestion, respectively. 2. Both earthworms and cockroaches have a one-way digestive system, where food travels in a single direction from the mouth to the anus. 3. Both earthworms and cockroaches have specialized regions in their alimentary canals for the absorption of nutrients, such as the intestine in earthworms and the stomach in cockroaches. b) [i] The biological cycle: The diagram is not provided, so it's not possible to determine the name of the biological cycle or answer the subsequent questions related to it. c) Organs associated with excretion in humans: - Kidneys - Urinary bladder - Ureter - Urethra Three diseases that affect the organ: - Kidneys: Chronic kidney disease, kidney stones, urinary tract infections - Urinary bladder: Bladder infections, bladder cancer, urinary incontinence - Ureter: Ureteral stones, ureteral obstruction, urinary reflux d) [i] Decay of organic matter: Decay of organic matter refers to the natural process of breaking down organic substances, such as dead plants and animals, into simpler compounds through the action of decomposer organisms. (ii) Two groups of organisms that cause decay of organic matter are bacteria and fungi. (iii) One other factor that causes decay is environmental conditions, including temperature, moisture, and availability of oxygen. (iv) The biological cycle that involves decay is the nutrient cycle or biogeochemical cycle. e) Mode of nutrition in carnivorous plants: Carnivorous plants have a unique mode of nutrition where they supplement their nutrient requirements by capturing and digesting small animals, usually insects. These plants typically grow in habitats where the soil lacks sufficient nutrients. To compensate for this, they have evolved specialized structures such as modified leaves, trapping mechanisms (such as pitcher traps or sticky glands), and digestive enzymes. When an insect or other small prey gets trapped, the plant secretes digestive enzymes onto it. These enzymes break down the prey's body into simpler compounds, such as amino acids and sugars, which the plant can then absorb and utilize as nutrients. Carnivorous plants primarily obtain nitrogen and other essential nutrients from the decomposition of the captured prey. This unique mode of nutrition allows them to thrive in nutrient-poor environments where other plants may struggle to survive.