digestive system + respiration Flashcards
in which two part of the digestive system is starch broken into maltose
Mouth (salivary glands) and the duodenum (from pancreatic juices)
In which part of the digestive system are lipids broken down into fatty acids and glycerol
The duodenum (made in liver and stored in gallbladder)
In which part of the digestive system is maltose turned into glucose, and by which enzyme
The ileum, eith the enzyme maltase
In which part of the digestive system are pepsides broken down into amino acids
The ileum
Describe and explain three things that happen in the stomach
Mechanical break down of food by churning
Protein broken into pepsides by pepsin
Hydrcholic acid kills bacteria
Describe and explain what happens in the duodenum
-Further digestion
Where Pancreas releases juices containing enzymes which break down starch into maltose and proteins into pepsides
-Emulsification of bile, turning large liquid droplets into an emulsion of smaller droplets
- pancreatic juices and bile together make alkaline condition which neutralizes bolus
Describe and explain what happens in the ileum and how
-Absorption of nutrients into the blood stream and assimilaition of them into where they are needed
-small intestine is long, has villi, and is semi permeable
Describe and explain six adaptations of the villi which aid with absorption
1) large surface area- to increase rate of diffusion
2) thin layer of epithelial cells - short distance for nutrients to diffuse through
3) blood capillary network - oxyegn is transported in and waste products are transported out
4) microvilli on surface -to further increase the rate of diffusion
5) muscle layer- to help the villi contract and move the contents of the ileum along
6) good supply of blood- to maintain a concentration gradient between bloodstrean and ileum
Describe and explain three adaptations of the ileum
Long and folded- to provide a large surface area
Contains villi- to increase the surface area
Semi permeable- to allow nutrients to diffuse through
State what is meant by a balanced diet
A diet consisting of various components to maintain health in appropriate proportions
What is the meaning of egestion
The process of the removal of undigested waste substances from the anus
What is the meaning of assimilation and give a short description of the process
The movement of digested food into the cells of the body where they are used. Small molecules are used to make large food molecules
What is the definition of a peristalisis
a series of wave like muscle contractions which move food through the digestive tract
When the circular muscles are relaxed but the longitutdional muscles are contracted, what does the gut look lkke
The gut is wide
What are the two role of bile
To emulsify fats by breaking them down from larger droplets into smaller droplets
And to neutralize the acidic food by providing it with alkaline conditions
What PH do enzymes in the small intestine work best at
PH 8/9 (alkaline)
What is the balanced symbol chemical equation for respiration
C6H12O6 + 6O2 ——-) 6CO2 + 6H2O + ATP
What does oxygen debt mean
The amount of oxygen required to completely oxidise lactic acid built from anaerobic respiration
What are four uses of ATP
Muscle contraction
Building large molecules
Cell division
Active transport
When an athlete beguns to race, why does his breathing rate increase
Because his muscles are more moving faster,
so are respiring more and need more atp
Thus so he needs to provide more oxygen to his muscles and remove more carbon dioxide from them
When an athlete is in the race, why does his heart rate begin to increase
Because he needs to transport more oxygen to his muscles
So amount of blood pumped per minute increases
When an athlete begins to stop running, why is he still panting
Because he needs to repay the oxygen debt caused from the lack of oxygen during anaerobic respiration
Explain why reducing the blood supply to the heart muscle cells can cause a heart attack
Less oxygen is being supplied
So less aerobic respiration
So body resorts to anaerobic respiration
Where a build up of lactic acid can cause the enzymes to denature as lactic acid is acidic
What is the meaning of egestion
The removal of undigested food from the anus
What are the five main processes of the digestuve system
Ingestion
Digestion
Absorption
Assimilation
Egestion
What is digestion
The mechanical and chemicak break down of food, converting large insoluble molecules into smaller soluble ones
Suggest the consequences of a diet that contains too much fat
Cholesterol and saturated fats can build up in the arteries
Can lead to obesity
Which can lead to hugh blood pressure, heart disease and diabetes
Which two parts of the digestive system produce amalyse
Mouth and pancreas
If i place lipid drops onto water
Explain what would halpen in each case if i added:
1)bile
2)bile and lipase
3)boiled lipase
4)bile and protease
Droplets would become smaller but would not dissapear
Droplets would dissapear
Droplets would remain the same
Droplets would become smaller but not dissapear
If i place droplets of lipid onto a tray of water
Explain why no droplets are seen after bile and lipase solution is added to the lipid and water mixture.
Bile emulsifies fats so increases the surface area
Bile also neutralizes the acidic conditions of the food for the alkaline optimum temperature of the lipase
Lipase is an enzyme which breaks down the bile into fatty acids and glycerol
Describe what happens to fish protein in the stomach(4marks)
Mechanically DIGESTED as the stomach churns the protein
Hydrochloric acid is released which kills bacteria
Because of the hydrochloric acid, the optimum ph is 2 so food turns acidic
And enzyme pepsin breaks down protein into peptides
Why is it important to use sterile bottles to store yeast
To remove pathogens
Why does the number of yeast cells decrease after fermentation
Yeast cells use up all the glucose to make ethanol
Excess amount of ethanol killw yeast cells
What is the word equation for fermentation
Glucose—-) carbon dioxode + ethanol.
(NO ATP)
Explain why the breathing rate is higher after intense excercose
Because the body has been respiring anaerobically,
the lactic acid produced requires oxygen to oxidise it
So the oxygen debt needs to be repaid
What colour does carbon dioxide indicator turn when carbon dioxide is present
Orange to yellow
Suggest why a cow(who eats grass) absorbs less percentage energy from repiration than a fish(who eats insects)
Because the grass contains cellulose which is difficult to digest
If im boiling a test tube with water with a mounted needle of food underneath to meausure the energy contents of food, explain why the value obtained will be more accurate if a larger volume of water is used
It will have less surface area to volume ratio, so less heat will be lost
In which two parts of the body does the enzyme pepsin break down protein into peptides
Stomach
Duodenum
The enzyme pepsin breaks_____ into _____
And the enzyme peptidase breaks _____ into_____
Pepsin breaks protein into peptides (trypsin also does this)
Peptidase breaks peptide into amino acid
If a patient produces hard and clumpy stool, what does this suggest about them?
They are constipated and have little water in their stool
If a patient produces watery stool, what does this suggest
They have diarrhea or food poisoning
Which organ releases insulin
The pancreas
During a food test, why is it important that the food is frost crushed up and dissolved in water
To dissolve any soluble sugars
Explain why in the lipid test a white layer will form
Ethanol is soluble in water so will dissolve,
Leaving behind the insoluble lipid emulsion layer on top
When investigating the energy content of food, why would dry food work best
Because it burns easily
In the experiment to investigate the energy content in food, explain one thing that you could do to increase the accuracy of the value you get for heat energy
Insulate the boiling tube with aluminum foil for example to minimize heat loss
Why does aerobic respiration produce more energy than anaerobic respiration
Because glucose is broken down completely, whereas in anaerobic respiration it is incomeoltelt broken down
Why is anaerobic respiration favoured in short bursts of exercise
Because it uses less oxygen, this is because there is not enough time for enough oxygen to be breathed in to break down glucose as there is not enough oxygen available yet for the intensity of excerise
Give five uses of energy in the body
-for active transport
-to keep the body warm, and maintain a constant temperature
-for muscle contraction and growth
-for cell division
-protein synthesis
Give the word equation for the oxygen debt
Lactic acid + oxygen —-) carbon dioxide + water
The hepatic portal vein transfers …. Blood form the… to the…
Deoxygenated
Small intestine
Liver
