Topic 5,6 (SME topic 2)

Question 1

organition principles

Answer 1

CELLULAR LEVEL;
heart muscle cell

TISSUE LEVEL;
heart muscle tissue

ORGAN LEVEL;
heart

ORGAN SYSTEM LEVEL;
circulatory system

ORGANISM LEVEL;
deer

Question 2

unicellular

Answer 2

an organism that is made of one cell such as “amoeba, paramecium, euglena”

Question 3

multi cellular

Answer 3

an organism that is made by multiple collections of cells such as humans and animals

Question 4

human digestive system

Answer 4

Digestion is a process in which relatively large, insoluble molecules in food (such as starch, proteins) are broken down into smaller, soluble molecules that can be absorbed into the bloodstream and delivered to cells in the body

Question 5

parts of the digestive system

Answer 5

alimentarty canal: runs from your mouth to anus

accessory organs ; which produce necessary substances

Question 6

alimentary canal

Answer 6

mouth
oesophagus
stomach
small intestine
large intestine

Question 7

teeth

Answer 7

used to mechanically break down food into smaller pieces that exposes more surface area for the action of enzymes

Question 8

oesophagus

Answer 8

used to push the food from the mouth to the stomach by peristalsis

Question 9

peristalsis

Answer 9

contractions that push the food to the stomach through the oesophagus

Question 10

the stomach

Answer 10

food will be further broken down by churning and will digest the proteins using proteases

Question 11

hydrochloric acid

Answer 11

will kill bacteria and create an acidic ph

Question 12

duodenum

Answer 12

the first party of the small intestine, where the process of digestion will finish and the alkaline ph is created by accessory organs such as the liver and the pangreas

Question 13

illium

Answer 13

where the absorption of digested food molecules will take place
this part of the small intestine is lined with villi which increases the surface area for absorption

Question 14

colon

Answer 14

where water is absorbed and faeces is formed

Question 15

rectum

Answer 15

where the faeces is stored before leaving thee body

Question 16

accessory organs

Answer 16

salivary glands
pancreas
liver
gall bladder

Question 17

salivary glands

Answer 17

secrete amylase enzymes for the digestion of starch

Question 18

pancreas

Answer 18

produces;
amylase - used to break down carbohydrates
lipase - used to break down lipids ( fats)
protease - used to breakdown protein

the secretions of the pancreas will increase the ph level of the fluid leaving the stomach to ensure the digestive enzymes can function properly

Question 19

enzyme

Answer 19

biological catalysts

they are called this because they are made from proteins which contain amino acids which are held together by bonds

the bonds can break in different conditions causing the enzymes to lose shape. this means the enzyme becomes denatured

Question 20

catalyst

Answer 20

something that speeds up a chemical reaction without being used up in the reaction

Question 21

enzyme uses

Answer 21

respiration digestion photosynthesis respiration

Question 22

lock and key model

Answer 22

is used to describe how enzymes work in the model the enzyme and substrate join together just like a key entering a lock. the shape of the key is important to determine whether it fits into the lock. the area of the enzyme that the substrate binds to is called the active site. when this happens the reaction occurs

Question 23

enzyme specify

Answer 23

refers to the fact that only enzymes with a specific shape can join together with a specific substrate just like only certain keys can fit into a lock.

this results in each enzyme mostly just catalysing one type of reaction

Question 24

enzyme and substrate shape

Answer 24

they are not the same it is said they are complementary to one another.

Question 25

how do enzymes work

Answer 25

the enzyme and substrate move around randomly due to their kinetic energy. sometimes the active site and the active site collide and join together forming an enzyme-substrate complex this is when the catalyst reaction occurs and the product is created

Question 26

digestive enzymes

Answer 26

They work outside of cells they digest large insoluble food molecules into smaller soluble molecules which can be absorbed into the bloodstream.

Question 27

metabolism

Answer 27

the sum of all the reactions happening in a cell or organism in which molecules are synthesised or broken down

Question 28

how does temperature affects rate of reaction with enzymes

Answer 28

the temperature gives the substrate and the enzymes more kinetic energy meaning they move around faster in the solution

Question 29

optimum temperature

Answer 29

the temperature with the highest rate of reaction

Question 30

denatured enzymes

Answer 30

when the temperature of the solution gets high enough it breaks the bonds of the amino acids# a denatured enzyme cannot bond to the substrate and can no longer catalyse reactions

Question 31

graph of the relationship between temp and rate of reaction

Answer 31

between 10 and 30 degrees the rate of reaction is steadily rising until it gets to the optimum temperature which on this graph is about 30 degrees after the optimum temperature the rate of reaction decreases because the enzyme become denatured.

Question 32

how ph level affects enzymes

Answer 32

when the ph is lower or higher the bonds between the amino acids break and denature

Question 33

graph of the relation between rate of enzyme activity and ph

Answer 33

the rate of reactivity rises up until a ph of 8-9 and the decreases due to enzymes denaturing

Question 34

how different enzymes around the body react in different phs

Answer 34

each enzyme is adapted so that its optimum ph matched the environment in which it functions for example: pepsin( found in stomach acid) has an optimum ph of 2 to prevent it from denaturing in the acid condition of the stomach urease has an optimum ph of 7 trypsin has an optimum ph of 8

Question 35

amylase required practical (explanation)

Answer 35

amylase is an enzyme that breaks down starch to maltose 1. the starch (polymer of glucose) is broken down by amylase to form maltose molecules 2. we use iodine to change the colour from orange to blue-black only if the starch hasn't broken down will it turn blue. if it has broken down to maltose it will remain the same colour. 3. we can use this to investigate how the rate of amylase changes at different ph levels

Question 36

required practical testing ph

Answer 36

1. first prepare a spotting tile and add iodine to each well 2. next measure out all the solutions needed; 1cm3 of ph7 buffer solution and 2cm3 amylase solution. There is also a second tube that contains starch solution. 3. when the experiment is ready to start add the amylase and buffer solution to a test tube and mix in the starch solution then immediately start the timer. At this time the amylase solution will start breaking down the starch the maltose.# 4. after 10 seconds use a pipette to transfer a couple of drops of the solution into the first well with the iodine. at this point the colour of the iodine should turn blue as the starch has not yet broken down.# 5. ten seconds later repeat the step in the next well 6. repeat these steps until the iodine remains the same colour this will indicate that the starch has been fully broken down into maltose. 7. at ph 7 this should be at 60 seconds the experiment can be repeated with different ph buffer solutions at ph 5 and 9 the reaction is slower because this is not the optimum ph for this enzyme. at ph 14 the enzyme is denatured so the starch is never fully broken down

Question 37

carbohydrase

Answer 37

breaks down carbs to simple sugars. amylase is carbohydrase which breakdowns starch into maltose which is then broken down into glucose by the enzyme maltose. amylase is made in the salivary glands, the pancreas and the small intestine..

Question 38

protease

Answer 38

Proteases are a group of enzymes that break down proteins into amino acids in the stomach and small intestine Protein digestion takes place in the stomach and small intestine, with proteases made in the stomach (pepsin), pancreas and small intestine

Question 39

lipase

Answer 39

Lipases break down lipids (fats) to glycerol and fatty acids. Lipase enzymes are produced in the pancreas and secreted into the duodenum lipase breaks down lipids into glycerol and three fatty acids

Question 40

bile

Answer 40

alkaline substance produced by the liver used to neutralise hydrochloric acid from the stomach. the enzyme in the small intestine have higher (more alkaline) optimum ph that those in the stomach. it breaks down large drops of fat into smaller ones which increases the surface are known as emulsification

Question 41

liver cells

Answer 41

produce bile which is stored in the gallbladder

Question 42

bile production

Answer 42

1. it is produced in the liver then flows to the gallbladder where it is temporarily stored until 2.until it is released into the duodenum of the small intestine via the bile duct 3. here it will perform several different functions to facilitate the process of digestion

Question 43

bile ph

Answer 43

since bile is an alkaline substance it will neutralise the hydrochloric acid in the stomach this is important because the enzymes in the small intestine cannot work properly in an acidic environment since their optimum ph is more alkaline (PH8) a ph that it is to low will change the shape of the active site of an enzyme so that the substrate cannot fit anymore and it will denature.

Question 44

what does bile do

Answer 44

bile produces salts that emulsify large fat droplets this is called emulsification which is necessary to increase surface area for the lipase to work. the alkaline conditions as well as the increased surface aree will allow the for an increase in the rate of lipid digestion

Question 45

different food tests

Answer 45

carbohydrates: iodine solution sugar: benedict's test for sugar proteins: biuret test lipids: ethanol

Question 46

test for starch

Answer 46

iodine test for starch 1. add food sample to test tube 2. a few drops of iodine is added to the food sample 3. iodine will change to a blue/black colour in the presence of starch 4. qualitative result instamtly

Question 47

test for glucose

Answer 47

benedict solution 1. use a bunsen burner and a stand to heat the water bath 2. in the water bath add the test sample 3. into the test sample add a drop of benedict's solution which will turn an orange/red colour if sugar is positive 4. boil the mixture for 5 minutes and observe the colour change if a reducing sugar is present

Question 48

test for protein

Answer 48

biuret solution 1. put the food sample in a test tube and add a drop of biuret solution 2. it will turn a purple colour in the presence of protein

Question 49

test for fats (lipids)

Answer 49

ethanol 1. the food sample is first mixed with ethanol then filtered before adding to distilled water 2. ethanol is a clear liquid it will turn into a cloudy emulsion if there is a positive result of lipids

Question 50

food tests chart

Answer 50

food test colour of reagent positive negative iodine orange black orange (starch) benedict blue orange blue (sugar) biuret blue purple blue (protein) ethanol colourless milky emulsion colourless (fats)

Question 51

gas exchange surfaces

Answer 51

Large surface area to allow faster diffusion of gases across the surface Thin walls to ensure diffusion distances remain short Good ventilation with air so that diffusion gradients can be maintained Good blood supply (dense capillary network) to maintain a high concentration gradient so diffusion occurs faster

Question 52

ribs

Answer 52

bone structure that surrounds the lungs

Question 53

intercostal muscles

Answer 53

muscles between the ribs which control movement causing inhalation and exhalation

Question 54

diaphragm

Answer 54

sheets of connective tissue and muscle at the bottom of the thorax that helps change the volume of the thorax to allow inhalation and exhalation

Question 55

trachea

Answer 55

windpipe that connects the mouth and nose to the lungs lined with goblet cells and ciliated ep

Question 56

resperitory system

Answer 56

lungs, trachea, bronchus

Question 57

bronchiole

Answer 57

branches into the bronchioles with termkinate in the aveoli