Chapter 5

1. Chapter 5 Obtaining Energy and Nutrients for Life

2. Autotrophs and Hetertrophs • Define an autotroph • Define a hetertroph • What process do autotrophs use to convert sunlight energy to chemical energy? • Name the pigment in plants capable of absorbing light energy • List the structural features of leaves which assist in enabling photosynthesis • What part do stems play in photosynthesis • What part do roots play in photosynthesis? • Do all cells of a plant carry out photosynthesis? Explain • Where in a cell is light energy transformed to chemical energy? • What structures of a plant facilitate delivery of sugars to non-photosynthetic cells throughout the plant? • In what form is carbohydrate typically stored in a plant? • List 10 different foods (sources of energy) that may be eaten by a hetertroph? • Are fungi hetertrophs?

3. Digestion • Define digestion • What are the main 4 steps that occur before a substance becomes available to the cells of an animal? Summarise each one. • What is the significance of the four different types of teeth found in most mammals? • What is the purpose (in terms of SA / V ratio) of breaking food down into smaller pieces? • What is the term for animals eating only; • Plants • Animals • Plants and animals • In what ways do the teeth of carnivores, herbivores and omnivores differ? • Why is digestion necessary in most mammals?

4. The Digestive System • Summarise the functions of; • The mouth • Salivary gland • Oesophagus • Liver • Stomach • Gall bladder • Pancreas • Small intestine • Caecum • Large intestine

5. The Digestive System • What is another name for the alimentary canal in people? • Define peristalsis • What is the enzyme contained in saliva? • When is pepsinogen converted into pepsin? • Why would it take over 50 years to digest a single meal without enzymes? • What is gastric juice made up of? • Approximately how long does food stay in the stomach? • What system does the body have to signal to the pancreas and gall bladder that food is in the stomach and will shortly be in the small intestine? • What the three main regions of the small intestine?

6. The Digestive System • Discuss why a lion would have canine teeth as well as incisors, pre-molars and molars • What type of teeth would a wombat have? • What is the process in the oesophagus that moves food to the stomach? • Approximately how long does it take to move food from the mouth to the stomach? • What enzyme is contained in saliva? • What is the function of saliva? • Gastric juice contains a mixture of …….? • Using a flow diagram, describe the process in the small intestine • Which enzyme acts upon maltose to break it down to glucose? • Which enzyme acts upon peptides to break them down into amino acids? • What function do villi serve in the small intestine? • Where and how are glycerol and fatty acids absorbed? • Where does most glycerol and fatty acid enter the blood stream? • What are the two main parts of the large intestine? • What are the main functions of the large intestine?

7. The Digestive System • What is faeces? • What influences the colour and texture of faeces? • Where does faeces leave the gut? • Explain flatus, how it occurs, what factors contribute to it and how it is expelled? • How much energy is absorbed from sugars and starches? • How much energy is absorbed from fats and proteins? • Summarise digestion in herbivores • Summarise foregut fermenters • Summarise digestion in nectar and pollen feeders • Summarise digestion in carnivores • List and explain two differences between carnivores and herbivores in terms of digestion structure and/or function • Utilising the key words list on page 125, identify 10 words that you are not thoroughly familiar with, and find their definitions and links to at least one other word from the list