Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
IB Biology Digestive
Object 6.1, H1, H2, H3, H4
| Question | Answer |
|---|---|
| 6.1.1 Explain why digestion of large food molecules is essential | Food has to be broken doing so that our bodies can use them. Food molecules have to be small enough to be absorbed by the villi in the intestine through diffusion, facilitated diffusion or active transport. |
| 6.1.2 Explain the need for enzymes in digestion | Enzymes are needed in the process of digestion, they break down the large food molecules into smaller ones so that they can be absorbed. Enzymes are vital as they speed up this process by lowering the activation energy required for the reaction to occur. |
| 6.1.3 State the source, substrate, products and optimum pH conditions for one amylase. | Enzyme: Salivary Amalayse Source: Salivary Glands Substrate: Starch Products: Maltose Optimum pH: pH 7 |
| 6.1.3 State the source, substrate, products and optimum pH conditions for one protease | Enzyme: Pepsin Source: Stomach Lining Substrate: Protein Products: Small Polypeptide Optimum pH: pH 1.5-2 |
| 6.1.3 State the source, substrate, products and optimum pH conditions for one lipase | Enzyme: Pancreatic Lipase Source: Pancreas Substrate: Triglycerides such as fats and oils Products: Fatty acids and Glycerol Otimum pH: pH 7 |
| 6.1.4 Draw/Label the Digestive System | Mouth Esophagus Stomach small intestines Large intestines Rectum Anus |
| 6.1.5 Outline the function of the stomach | Stomach: secretes HCL to kill off bacteria that could cause food poisoning. Also provides the optimum conditions for the enzyme pepsin to work in |
| 6.1.5 Outline the function of the small intestine | The small intestine is where the final stages of digestion occur. Main function of the small intestine is the absorption of the small food particles resulting from digestion. Many villi for absorption |
| 6.1.5 Outline the function of the large intestine. | The large intestine moves the material that has not been digested from the small intestine and absorbs water. This produces solid feces which then go through the anus. |
| 6.1.6 Distinguish between absorption and assimilation | Absorption occurs when the food enters the body as the food molecules pass through a layer of cells and into the bodies tissues Assimilation occurs when the food molecules becomes part of the bodies tissue. Absorption is followed by assimilation |
| 6.1.7 Explain how the structure of the villus is related to its role in absorption and transport of the products of digestion | Great number of them so this increases the surface area for absorption in the small intestine. |
| 6.1.7 Explain how the structure of the villus is related to its role in absorption and transport of the products of digestion | Many microvilli increase the surface area for absorption further. The blood capillaries in the villus are very closely associated with the epithelium so that the distance for the diffusion of the food molecules is small. |
| 6.1.7 Explain how the structure of the villus is related to its role in absorption and transport of the products of digestion | Finally, there is a lacteal branch at the centre of the villus which carries away fats after absorption. |
| H.2.1 State that digestive juices are secreted into the alimentary canal by glands. Includes... | Salivary glands, gastric glands in the stomach wall, the pancreas and the wall of the small intestine. |
| H.2.2 Explain the structural features of exocrine gland cells | Secretory cells form a single layer around the duct. Secretory cells are surrounded by a basement membrane. Secretory cells of an acinus will release the secretion into the lumen of the duct. Ducts open onto surfaces such as the skin or another c |
| H.2.3 Compare the composition of saliva | Consist of: water, electrolytes, salivary amylase, mucus, lysozyme |
| H.2.3 Compare the composition of gastric juice | Consists of: water, mucus, enzymes (pepsin, rennin), HCl |
| H.2.3 Compare the composition of pancreatic juice | Consist of: pancreatic juice (from pancreas) water, bicarbonate, enzymes (amylase, lipase, carboxypeptidase, trypsinogen) |
| H.2.4 Outline the control of digestive juice secretion by nerves, using the example of secretion of gastric juice. | Nervous -Smell of food leads to a reflex -Gastric juices are released into stomach |
| H.2.4 Outline the control of digestive juice secretion by hormones, using the example of secretion of gastric juice. | Hormonal -The physical presence of food in the lower region of stomach stimulates the endocrine cells in stomach wall to release gastrin -Gastrin travels to blood stream to target tissue which are gastric juice cells of stomach |
| H.2.5 Outline the role of membrane bound enzymes on the surface of epithelial cells in the small intestine in digestion. | Some of the enzymes are immobilized on the membranes of the intestinal epithelium cells. The active sites of the enzymes are oriented toward the lumen of the intestine. They remain functional even when epithelial cells have been shed off into the lumen. |
| H.2.6 Outline the reasons for cellulose not being digested in the alimentary canal | Human lack the digestive enzyme cellulose, the dietary cellulose remains undigested is made into the feces. |
| H.2.7 Explain why pepsin and trypsin are initially synthesized as inactive precursors and how they are subsequently activated. | Pepsinogen and trypsinogen are inactive forms of enzymes. This is done to prevent self-digestion of the cells -Produces inactive enzymes known as the zymogens |
| H.2.9 Explain the problem of lipid digestion in a hydrophilic medium and the role of bile in overcoming this. | Lipids too large for Villi -Bile molecules have a hydrophobic end and a hydrophilic end which emulsifies lipids -Lipase is water-soluble but it does have a hydrophobic active site The increased surface area allows lipase greater access to its subs |
| -4 mark- H.3.3 Explain the structural features of an epithelial cell of a villus as seen in electron micrographs, including microvilli, mitochondria, pinocytotic vesicles and tight junctions. | Goes in through all types - Diffusion - Endocytosis - Facilitated Diffusion - Pumped in by active transport |
| H.3.3 Explain the structural features of an epithelial cell of a villus as seen in electron micrographs, including microvilli, mitochondria, pinocytotic vesicles and tight junctions. -continued- | Go in epithelial cell and across comes out the other side go into capillaries/lacteal -Regulating absorbition -Can come in one way and exit different way -Every combination |
| H.3.3 Explain the structural features of an epithelial cell of a villus as seen in electron micrographs, including microvilli, mitochondria, pinocytotic vesicles and tight junctions. -continued- | We want them to have to go through the cells as a form of regulating -tight junctions, like sewing them together to make them tight |
| H.3.3 Explain the structural features of an epithelial cell of a villus as seen in electron micrographs, including microvilli, mitochondria, pinocytotic vesicles and tight junctions. -continued- | Pinocytotic Vesicles - Things that are large are gonna got through endocytosis - Packaged in vesicle towards the microvilli end |
| H.3.4 List the materials that are not absorbed and are egested. | What ever is not absorbed is pooped out - Cellulose come from plant material - Bile pigments - Bacteria in colon - Intestinal cells |
| H.4.1 Outline the circulation of blood through liver tissue, including the hepatic artery, hepatic portal vein, sinusoids and hepatic vein. | It is six-sided and made of liver cells called hepatocytes. The lobule is fed by two sources of blood: the hepatic artery from the heart and the hepatic portal vein from the intestines, stomach and spleen (supplying venous blood laden with nutrients) |
| -4 Mark- H.4.1 Outline the circulation of blood through liver tissue, including the hepatic artery, hepatic portal vein, sinusoids and hepatic vein. -continued- | The sinusoids have gaps between the cells that make up the wall so blood flowing along them is in close contact with the hepatocytes. Inside the sinusoids are star-shaped hepatic macrophages, called Kupffer cells |
| H.4.1 Outline the circulation of blood through liver tissue, including the hepatic artery, hepatic portal vein, sinusoids and hepatic vein. -continued- | Kupffer cells, which remove materials such as bacteria and worn-out blood cells from the blood as it flows past. The hepatic vein drains the liver and empties into the inferior vena cava. |
| H.4.2 Explain the role of the liver in regulating levels of nutrients in the blood. | Some digested materials could be toxic at high levels in the blood. There is a need for nutrients like glucose to be controlled within certain levels in the blood so that it is maintained. |
| H.4.3 Outline storage of nutrients | The liver converts nutrients into proteins, fats, and carbohydrates. The liver manufactures about half of the body’s cholesterol Sugars are stored in the liver as glycogen and then broken down and released into the bloodstream when glucose is needed |
| H.4.6 Process of erythrocyte and hemoglobin break down. | Red blood cells are destroyed, after about 4 months by Kupffer cells. Hemoglobin is converted to a yellow pigment (bilirubin), the iron is stored (also carried in the blood to bone marrow) and the protein is broken down to amino acids. |
| H.4.6 Process of erythrocyte and hemoglobin break down. -continued- | Bilirubin is changed into a slightly different form and then it is transferred to the bile (in bile pigments), released into the intestine, and it is excreted in feces. |
Created by:
tamlyd000
Popular Biology sets