Animal Tissues, Organs and Organ Systems Flashcards
What is the digestive system (in mammals)
An organ system where several organs work together to digest and absorb food
What are the different parts of the digestive system
Mouth Gullet Stomach Small Intestine Large Intestine
Define Digestion
The process of breaking down large insoluble food molecules into small soluble molecules
What is the purpose of the mouth in the digestive system
To begin breaking down food
What is the purpose of the stomach in the digestive system?
To break down food and sterilise it
What is the point of the small intestine in the digestive system?
To absorb soluble food molecules
What is the point of the large intestine in the digestive system?
To absorb water
What are enzymes?
Catalysts used inside the body to speed up a metabolic reaction
How does temperature affect enzyme acid
Causes an increase in rate of reaction until after its optimum temperature after which the rate of reaction will decrease as enzymes will be denatured
How does pH affect enzyme acid
Causes an increase in rate of reaction until after its optimum pH after which rate of reaction will decrease as enzymes will be denatured
How do enzymes aid in digestions?
They catalyse specific reactions dues to the shape of their active site being complimentary to the shape of the food molecules
Describe the required practical investigating the effects of pH on rates of reaction the amylase enzyme
> Put a test tube of amylase and a test tube of starch solution in a water bath till they are the same temperature
Add amylase to the starch
Every 30s remove a drop and put it on a spotting tile containing iodine solution
Record how long it takes for the starch to be digested
Repeat this at different pH values using different buffer solutions
What is the lock and key model?
A model to help explain enzymes, when the molecule(key) goes into the enzyme(lock) the reaction is speed up. Only one type of “Key” can get in a “lock”
Where are proteases made?
- Stomach
- Pancreas
- Small intestine
Where is amylase made?
- Salivary glands
- Pancreas
- Small Intestine
Where are lipases made?
- Pancreas
- Small Intestine
What do carbohydrase’s do
Break down carbohydrates into simple sugars
What does amylase do?
Break down starch into glucose
What do proteases do?
Break down proteins into amino acids
What do lipases do?
Break down lipids into glycerol and fatty acids
What is bile and what does it do
It is a alkaline that neutralises the acid from the stomach and emulsifies fat to increase area for enzyme action. Alkaline is also more optimal for lipases to act on
Where is bile made and where is it stored?
Made: Liver
Stored: Gall Bladder
What is the test for starch
Iodine: Yellow-Red -> Blue-Black
What is the test for sugars
Benedict’s Solution: Blue -> Brick Red
What is the test for proteins
Biuret Reagent: Blue -> Purple
What is the test for proteins
Biuret Reagent: Blue -> Purple
What is the heart?
An organ that pumps blood around the body in a double circulatory system
What are blood vessels leading in and out of the heart?
(right to left) Vena Cava Pulmonary artery Aorta Pulmonary Vein
What is the path of blood through the right side of the heart
Vena Cava
Right Atrium
Right Ventricle
Pulmonary Artery
What is the path of blood through the left side of the heart
Pulmonary Vein
Left Atrium
Left Ventricle
Aorta
What are the different components of the lungs
Trachea
Bronchi
Bronchioles
Alveoli
What is the test for lipids
Ethanol: Clear - Cloudy
What happens in the process of inhalation
- Intercostal muscles contract
- Ribs move up and out
- Diaphragm flattens
- Volume of chest increases
- Pressure in chest decreases
- Air is drawn into lungs
What happens in the process of exhalation
- Intercostal muscles relax
- Ribs move down and in
- Diaphragm Bends
- Volume of chest decreases
- Pressure in chest increases
- Air is pushed out of the lungs
How are the alveoli adapted for gaseous exchange
Have a very large SA: Vol
Have a rich blood supply
Very thin for short diffusion
Moist for easy diffusion
State the process of the alveoli
Air in
Oxygen diffuses into the blood stream
Carbon dioxide diffuses out the blood stream
Air out
Why are there valves in the heart
To prevent the back flow of blood through the heart
What is the natural pacemaker and where is it located
A group of cells in the right atrium that control the resting heart rate of the heart
What is an artificial pacemaker
An electrical device implanted in the heart used in lieu of the natural pacemaker that controls the heart rate
What is an artery
A blood vessel that transports blood away from the heart to other cells
What is a vein
A blood vessel that transports blood back to the heart from other cells
What is a capillary
A blood vessel that enables the diffusion of substances in and out of it and cells
What are the adaptations of arteries
Thick walls - High pressure
Thick layer of muscles and elastic tissue - pumping blood
Small lumen
What are the adaptations of arteries
Thick walls - High pressure
Thick layer of muscles and elastic tissue - pumping blood
Small lumen
What are the adaptations of veins
Relatively thin walls - low pressure
Large Lumen
Often have valves - prevent backflow
What are the adaptations of capillaries
Tiny Vessel with narrow lumen
Wall a single cell thick for diffusion
What is a double circulatory system
One in which there are two different loops for blood circulation. One is oxygenated and the other is deoxygenated.
What are the different components of blood and their percentages
Plasma - ~ 55%
Red blood cells - ~45%
White blood cells ->1%
Platelets - >1%
What is blood plasma’s function
As a transport medium for various things
What is the purpose of red blood cells
To transport oxygen from the lungs to other cells
What is the purpose of white blood cells
To defend against dangerous microorganisms by producing antibodies and antitoxins(lymphocytes) or by engulfing microorganisms(phagocytes)
What is the purpose of platelets
Help in blood clotting - trigger enzyme controlled reactions that turn fibrinogen into fibrin that produces a network of protein fibres
What are the features of a red blood cell
No nucleus - more space for haemoglobin
Biconcave disks - high SA : Vol
Packed with red pigment haemoglobin which binds to oxygen
What is cardiovascular disease
Diseases that involve the heart or blood vessels
What is coronary heart disease
A disease in which the coronary arteries are blocked up/ narrowed by fatty deposits, preventing enough blood getting to the muscles of the heart
What are stents
Cage used to widen the coronary arteries
Stent and balloon fed into artery
Balloon inflated
Stent left behind, keeping artery open
What are statins
Drugs that reduce blood cholesterol levels and slows down the rate at which fatty material is deposited
Why are leaky heart valves dangerous
Make the heart less efficient
Affected people may become breathless
Without treatment patient will die
What can doctors use to replace a leaky valve
A mechanical valve - lasts whole life, needs medication
A biological valve - from pig or cow - lasts 12 - 15 years, doesn’t need medication
When is a heart transplant necessary
When a patients heart fails
What are the advantages and disadvantages of a mechanical heart
Can keep a patient alive while waiting for a heart transplant
Patients often bed ridden
What are the advantages and disadvantages of a heart transplant
Very effective
Have to wait a long time for a donor
Define Health
A state of physical and mental well being
What causes ill health
Disease
Diet
Stress
Other life situations
List some ways in which diseases interact with each other
Defects in immune system may cause higher susceptibility to infectious diseases
Viruses living in cells can trigger changes leading to cancer
Immune reactions caused by pathogens can trigger allergies
Severe physical ill health can lead to depression and other mental illnesses
What is the impact of non - communicable diseases
Individual - Pain, financial, mental pain
Family - mental pain, financial
Society - cost nations huge sums of money
Define correlation
A link that suggests a cause but does not prove it
Define causal mechanism
A proven cause of something else
What risk factor increase someone’s chance of disease
Lifestyle: smoking, lack of exercise, overeating
Environmental: Ionising radiation, UV light, Second hand smoke
What is cancer
The uncontrollably growth and division of cells
What causes cancer
The mutation of cells due to the disruption of the DNA in Cells
Define tumour
An uncontrolled growth of abnormal cells
What is a benign tumour
A tumour that does not attempt to spread to other parts of the body
What is a malignant tumour
A tumour that spreads to other parts of the body through the blood stream
What are some causes of cancer
Genetic history
Carcinogens such as asbestos
Ionising radiation e.g. UV light
Viral infections
How does smoking affect cardiovascular disease
Narrows the blood vessels
Nicotine increases heart rate
How does smoking affect the lungs
Stops cilia working, allows dirt to accumulate
CO is poisonous
Can develop bronchitis, cancer, COPD
How does smoking affect unborn babies
Can lead to:
premature births
low birth weight babies
stillbirths
How does obesity affect the risk of type 2 diabetes
Increases chance of type 2 diabetes
How does obesity, exercise and diet affect the risk of cardio vascular diseases
Less exercise, worse diet, obesity increases chance
How does alcohol affect liver and brain functions
May develop liver cirrhosis
Alcohol is a carcinogen
Long term alcohol causes brain damage
Alcohol causes lowered inhibition and lowered reaction times
How does alcohol affect unborn babies
May cause: Miscarriage Stillbirths Premature births Low birth weight Fetal alcohol syndrome
What risk factors are there to do with ultraviolet light
Increases risk of skin cancer
