New (9-1) AQA GCSE Biology Paper-1 Organisation Complete Revision Summary
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AQA GCSE Paper 1: Complete Revision Summary
ORGANISATION
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4.2 Organisation
Organisation hierarchy
Human Digestive System
Circulatory System
Heart and the blood vessels
Blood
Coronory Heart Disease
Non Communicable Disease
Respiratory System
Plant Tissues
Plant Organ System
Transpiration
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LIVING SYSTEM HIEARARCHY
CELLS
Nerve Cell
Muscle Cell
TISSUES
Muscular tissue
Epithelial tissue
Glandular tissue
ORGANS
Stomach, kidney, liver, pancreas, Heart
ORGAN SYSTEM
Circulatory System,
Digestive System
Nervous System
Excretory System
ORGANISMS
Digestion
It is the process of breaking down large insoluble food particles in the food into soluble small particles which can then be absorbed into the blood Banner 4
DIGESTION PROCESS
INGESTION –
It happens with the help of mouth and tongue
Taking in of food with the help of mouth.
The teeth and tongue helps in churning the food and mixing with saliva.
DIGESTION –
It happens with the help of stomach, intestine , pancrease and liver
Breakdown of large insoluble particle into small soluble ones
ABSORPTION –
Small Intestine
The process by which digested food particles are absorbed into the blood
ASSIMILATION –
In the body cells
Using the absorbed food for releasing energy and in body processes.
EGESTION –
By rectum and Anus
Getting rid of undigested food materials.
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BILE JUICE
It is the green yellow alkaline liquid which is produced in the liver and stored in the Gall Bladder.
It performs two major Functions:
NEUTRALIZATION
The food that comes from the stomach is acidic and the enzymes of the intestine can work in alkaline conditions.
The bile neutralizes the food that comes from the stomach and makes it alkaline so that the enzyme released in the intestine can work effectively.
EMULSIFICATION OF FATS
For lipase to work, the fat must be broken down into small droplets to increase the surface area for the lipase to function.
The bile perform this function of emulsification of fats for the efficient working of lipase.
Principal source of energy Fuel for respiration Storage molecules like starch and glycogen Structure molecule like cellulose
Proteins
Pulses, chicken Meat, poultry Eggs, Beans Nuts
Amino Acids
Protease
Stomach and small intestine
Components of muscles. Required for growth and repair. components of enzymes Hormones like insulin
Fats
Butter, Oil; Margarine,
Fatty Acids + Glycerol
Lipase
Small Intestine
Insulates the body Reserve source of Energy components of cell membrane
ENZYMES
They are biological catalyst that increases the rate of a biological reaction without being used up.
They increases the rate of the reaction by providing an alternative route that works by lowering the activation energy.
They are protein in nature so they are sensitive to heat and pH.
LOCK AND KEY MODEL
Enzymes are highly specific due to the active site. As the active site has a shape complimentary to the substrate. So the specific substrate molecule can fit into the active site of the enzyme.
FACTORS AFFECTING ENZYME ACTIVITY
SUBSTRATE CONCENTRATIONENZYME CONCENTRATION
FACTORS AFFECTING ENZYME ACTIVITY
Temperature
Denaturation is the change in the shape of the enzyme with increase in temperature and pH beyond optimum which results in the change in shape of the active site As a result, substrate molecules can no longer fit into the active site decreasing the rate of the reaction.
Rate of reaction increases as particles gain kinetic energy and they collide more increasing
The optimum temperature. It is the point where the enzyme activity is the highest.
pH
Different enzymes has different pH optimum.
Stomach enzymes works in acidic conditions which are maintained by hydrochloric acid Intential enzymes works in alkaline pH maintained by bile
CIRCULATORY SYSTEM
The system that provides the bosy with oxygen, nutrient, hormones and all the essential things required by the body to survive. It also eliminate the waste products. PUMPING ORGAN
It the heart that pumps the transporting medium all around the body.
HEART
TRANSPXTING MEDIUM
It is the blood which contains all the dissolved substances and oxygen required by the body.
BLOOD
VESSELS
They carries the blood from one part to another.
ARTERIES
VEINS
CAPILLARIES
BLOOD
BLOOD PLASMA
It is the liquid component of the blood.
It makes 55% of the blood.
It is composed of:-
Glucose
Amino Acids
Hormones
Waste Products like Urea
Carbon Dioxide
BLOOD CELLS
RED BLOOD CELLS
It transport oxygen all around the body. It is a specialised cells
Biconcave disc
Increases the surface area for oxygen transport
No nucleus
To provide more room for oxygen contains haemoglobin
Binds with oxygen to carry it around the body
WHITE BLOOD CELLS
They are soldiers of the cells
The protect the body from infections
They are made up of lymphocytes which produce antibodies.
They also have phagocytes which engulfs the pathogen
PLATELETS
They are involved in blood clotting
They have fibrin proteins which forms the mesh around the blood
NEED FOR CIRCULATORY SYSTEM
LOW SURFACE AREA TO VOLUME RATIO
Multicellular organisms due to their bigger size have very low surface area to volume ratio.
As a result, diffusion alone is not effective to meet the demands of the cell so it requires a circulatory system.
METABOLICALLY ACTIVE
The multicellular organisms are metabolically active. So they need constant supply of oxygen and food and constant removal of waste products.
MULTICELLULAR
Being multicellular many cells are deep and the diffusion distance is larger.
So they need a circulatory system that transport substance deep inside the cells.
DOUBLE CIRCULATON
Pulmonary vein
AORTA
In One complete cycle the blood is pumped into the heart twice.
It involves two circulation: Pulmonary: Circulation between Lungs and Heart
Systemic Circulation: Circulation between heart and the body
Double circulation makes the circulation more efficient by preventing the mixing of oxygenated blood and helps to alter the pressure from the different chambers of the heart
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Heart
Heart is the pumping organ
Working all day and night
It has four chambers
Atrium are at the top and Ventricles are at the bottom.
Ventricles have thicker wall than the atrium.
Left Ventricle have the thickest wall amongst all other chamber
BLOOD VESSELS
ARTERIES
VEINS
CAPILLARIES
Carries the blood away from heart
Comes the blood to the heart
Connects arteries and veins
Has thick muscular elastic wall
Thin elastic wall
Once Cell thick
Narrow Lumen
Wider Lumen
Very small Lumen
They do not have valves
They have valves
They do not have valves
The blood flows at a high pressure
The blood flows at a lower pressure
The blood flows at a lower pressure.
They carry oxygenated blood except pulmonary artery.
They carry deoxygenated blood except pulmonary vein
They carry both oxygenated and deoxygenated blood.
CORONORY HEART DISEASES
Coronory Artery that supplies the blood to the arteries become narrow.
The fatty materials like cholesterol gets deposited and narrow the artery.
The narrowed artery reduced the blood flow to the heart.
The blood flow to the heart is reduced.
The heart do not get enough oxygen.
This causes heart pain, chest pain and heart attack.
Treatment of Coronory Heart Disease.
A Stent is placed with the baloon in the blocked artery.
The blocked artery is opened by inflating the baloon.
The metal mesh stent keep the stent in place.
This resumes the blood flow.
People can also be given statin which lowers the blood cholesterol and prevent the deposition of the cholestrol.
The blood flow to the narrow artery is byepassed to the graft taken from another part of the body
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PROBLEMS TO THE HEART
LEAKY VALVES
Due to increases pressure of blood flow the valves start to leak.
VALVE REPLACEMENT
The valves made up of metal or polymers or the biological valves from animals can be used to replace the faulty valve
IRREGULAR HEART BEAT
The natural pacemaker which are the group of cells at the top of the right atrium that regulates the heart beat do not function properly.
ARTIFICIAL PACEMAKER
Electrical devices called the artificial pacemaker takes over the function of natural pacemaker.
HEART FAILURE
When the heart do function properly
HEART TRANSPLANT OR ARTIFICIAL HEART
Artificial heart or heart transplant from the donor.
HUMAN GAS EXCHANGE SYSTEM
MECHANISM OF BREATHING
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GAS EXCHANGE
ALVEOLI GREATER SURFACE AREA SHORTER DIFFUSION DISTANCE STEEP CONCENTRATION GRADIENT
ORGANISATION IN PLANTS
CELLS TISSUES
Xylém and Phloem
Palisade mesophyll tissue
Spongy mesophyll tissue
ORGANS – Root, Stem and Leaves ORGAN SYSTEM – Water Transport System ORGANISMTRANSPIRATION
Transpiration is the loss of water from the surface of the leaves in the forms of water vapours.
In plants it takes place through the stomata.
FACTORS AFFECTING TRANSPIRATION
MEASURING RATE OF TRANSPIRATION
Potometer is the device which is used to measure the rate of water uptake or the rate of transpiration.
The movement of bubble is an indicator of water movement which in turn shows the rate of transpiration
ADAPTATIONS TO LIMIT TRANSPIRATION
Cuticle layer on the leaf which is waterproof prevent rate of transpiration
Stomata are present on the lower surface to reduce rate of transpiration.
Some plants stomata open is night and closes in day.
In plants like cactus the leaves are reduced to spines to decreases the surface area for water loss.
Some plants have sunken stomata.
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