Organisation Flashcards
What are cells for organisms?
Cells are basic building blocks of all living organisms
What is a tissue?
A tissue is a group of cells with similar structure and function
What are organs
Organs are made up of tissues working together to do a specific functions. They are organizing in an organ system which work together to form organisms.
What is the digestive system
The digestive system is an example of an organ system in which several organs work together to digest and absorb food.
Enzymes catalyze specific reactions in the living organism due to the…
shape of the active site
Living things produce enzymes that act as …
A biological catalyst
What’s the use of enzymes
Enzymes make the chemical reactions work
Enzymes reduce the need for a high temperature and speed up the useful chemical reactions in the body
What is catalyst
A catalyst is a substance which increases the speed of reaction without being changed or used up in the reaction
What happens if the substrate doesn’t match the enzymes active site
The reaction won’t be catalyzed (The speed of reaction will not increase)
Explain the enzyme action using the lock and key theory
The active site changes shape as the substrate binds into it to get a tighter fit (Induced fit) then the enzyme produces products. (the enzyme is unchanged after the reaction)
How do you calculate the rate of reaction
1000/time = rate
What are the principles of organization
Cell > Tissue > organ > Organ system > Organism
Cells are the basic building blocks of all living things
A group of cells with similar structures and functions is called a tissue
An organ is a combination of tissues carrying out a specific function (ex. Heart)
Organs work together with an organ system
Organ systems work together to form whole living organisms
What’s the purpose of a digestive system 
The digestive system is to break down large food molecules into smaller soluble molecules which are then become products absorbed into the bloodstream. The rate of these reactions are increased by enzymes. 
What kind of tissue does the stomach contain
Muscle tissues and glandular tissue which releases enzymes
 (Enzymes = protein molecules that increase the rate of reaction)
Food contains three main nutrients: what are they
Carbohydrates - starch
Proteins and lipids - fats
Carbohydrates, proteins and lipids are large molecules that have to be digested. Why?
All of these molecules are too large to be absorbed into the bloodstream so they have to be digested
What happens during digestion
Large molecules are broken down into small soluble molecules by enzymes. The small molecules can then be absorbed into the bloodstream.
Explain the process of digesting
First food is chewed in the mouth.
Enzymes in the saliva begin to digest the starch into smaller sugar molecules.
The food then passes down the esophagus into the stomach.
In the stomach enzymes begin the digestion of proteins.
The stomach contains hydrochloric acid which helps the enzymes to digest proteins.
The food spends several hours in the stomach
The churning action of the stomach muscles turns the food into a fluid increasing the surface area for enzymes to digest.
The fluid then passes through the small intestine and chemicals are released into the small intestine from the liver and pancreas.
The pancreas releases enzymes which continue the digestion of starch and protein. They also start the digestion of lipids.
The liver releases bile which helps to speed up the digestion of lipids.
Bile also neutralizes the acid released from the stomach.
The walls of the small intestine release enzymes to continue the digestion of proteins and lipids.
The small food molecules produced by digestion are absorbed into the bloodstream either by the diffusion or active transport.
Now the fluid makes its way through the large intestine where the water is absorbed into the bloodstream.
Lastly the FECES is released from the body.
What are the products of digestion used for
To build a new carbohydrates, lipids and proteins by the body
What is some of the glucose used for
Respiration
What do carbohydrates break down into
Simple sugars
What does Amylase (a carbohydrate) breakdown
Starch
What do protease breakdown into
They break down proteins to amino acids
What do lipases breaking down
They break down lipids (fats) to glycerol and fatty acids
What do enzymes do
Enzymes catalyze chemical reactions (speed up)
What are enzymes
Enzymes are large protein molecules and they have a groove on the surface called active site.
They are large proteins that are made up of chains of amino acids.
What does the active site do
The active site is where the substrate attaches to it to break down and produce products 
Proteins are broken down by enzymes what are they called
Proteases
What are proteins
Proteins are long chains of chemicals called amino acids 
When we digest proteins what happens
The protease enzymes convert the protein back to the individual amino acids which are then absorbed into the bloodstream.
When the amino acids are absorbed by the body cells they are joined together in a different order to make human proteins
What does starch consist of
Starch consist of a chain of glucose molecules
Carbohydrates are broken down by enzymes. What is this called
Carbohydrases. In the case of starch this is called amylase.
When carbohydrates like starch are digested. what do we produce?
Simple sugars
Where is amylase found
In the saliva and pancreatic fluid
A lipid molecule consists of what
A molecule of glycerol attached to 3 molecules of fatty acids
What are lipid molecules digested by
Enzyme lipase.
What does enzyme lipase produced
Glycerol and fatty acids
Where can you find lipase
The pancreatic fluid and small intestine
Where is bile made and stored
Bile is made in the liver and stored in the gall bladder
What does bile do
Speed up the digestion of lipids. (Bile is NOT an enzyme)
Bile converts large lipid droplets into
Smaller droplets
Bile is an alkaline. what does it help with?
Neutralizing the hydrochloric acid from the stomach.
It also emulsifies fat to form small droplets which increase the surface area.
The alkaline conditions and large surface area increases the rate of what
Fat (lipid) breakdown by lipase
As we increase the temperature what happens to the activity of the enzyme
The activity of the enzyme increases (The reaction gets faster)
As the temperature increases why does the activity of the enzymes increase
The enzymes and substrates are moving faster so there are more collision per second between the substrate and the active site
At a certain temperature the enzyme is working at the fastest possible rate.
What is that called?
Optimum temperature
During the optimum temperature. what is there a maximum frequency of?
There is a maximum frequency of collisions between the substrate and active sites
After the optimum temperature what happens
The enzyme decreases to 0
After the optimum temperature why does the enzyme decreased to 0
At high temperatures that enzyme molecule vibrates and the shape of the active site changes so the substrate will no longer fits into the active sites (Active site has denatured) and the enzyme can no longer catalyze the reaction.
What’s the normal temperature of a human being
30°
If we make the pH more acidic or more alkaline what happens to the activity
It drops to 0
If the enzyme works best at an acidic pH what could this be
This could be a protease enzyme in the stomach
If the enzyme works best at an alkaline pH what could this be
This could be an enzyme released from the pancreas into the small intestine (eg. lipase)
What are the problems when investigating the effects of the ph on the rate of amylase enzymes (Required practical)
The color change tends to be gradual and can be difficult to see when the reaction has finished
Define the heart
The heart is an organ that pumps blood around the body in a double circulatory system.
What’s the job of the right ventricle of the heart
Pumps oxygenated blood to the lungs where gas exchange takes place
What’s the job of the left ventricle of the heart
Pumps deoxygenated blood around the rest of the body
What are the three types of blood vessels that the body contains
Veins
capillaries
Arteries
Define blood
Blood is a tissue consisting of plasma where the red blood cells, white blood cells and platelets are suspended
What do roots, stem and leaves form?
They form a plant organ system for transport of substances around the plant
How are roots hair cells adapted to their function
They are adapted for efficient uptake of water by osmosis, And mineral ions by active transport.
What is the role of the stomata and guard cells
To control gas exchange and water loss
What is the phloem composed of
Tubes of elongated cells
How can cell sap move from one phloem to the next through what
Pores in the end wall
What is movement of the food molecules through the phloem tissue called
Translocation
How does phloem tissue transport dissolve sugars
From the leaves to the rest of the plant for immediate use or storage
How do xylem tissues transport water and minerals ions
From the roots to the stem and leaves
How are xylem tissues composed for transporting water and mineral ions
It is composed of hollow tubes strengthened by lignin for the transport of water in the transpiration stream.
Define transpiration
The movement of water from the roots through the xylem and out of the leaves
Define translocation
The transport of food substances (Mainly dissolved sugars) made in the leaves to the rest of the plant for immediate use or for storage. The transport goes in both directions.
What is the leaf
The leaf is a plant organ
The plasma is the liquid part of blood. what do you find in the plasma?
Red blood cells
white blood cells
Platelets
What does blood plasma transport
Soluble digestion products (Like glucose and amino acids) from the small intestine to other organs
Carbon dioxide (Produced by aerobic respiration) from the organs to the lungs to be breathed out.
The waste product urea From the liver to the kid needs to become urine 
What do red blood cells do
They transport oxygen from the lungs to the body cells
What do red blood cells contain (it’s an oxygen carrying molecule)
Hemoglobin
Hemoglobin + oxygen ^lungs> ??
Oxyhaemoglobin
What’s the process of red blood cells
Hemoglobin and oxygen combine in the lungs to produce oxyhemoglobin then the red blood cells travel to the organs where the oxyhemoglobin releases the oxygen
Red blood cells have no nucleus what does this mean
They have more space for hemoglobin
What do scientists call the red blood cells shape
Biconcave disc (It gives the red blood cells a greater surface area so Oxygen diffuses in and out rapidly)
What do white blood cells form
Part of the immune system for example by making antibodies
What does the white blood cell contain (structure)
It contains a nucleus (This contains DNA which encodes the instructions that the white blood cells need to do their job)
What’s the job of platelets
Platelets are tiny fragments of cells and their job is to help the blood to clot at a wound
What do white blood cells help with
Defending against infections
What are the uses in donated blood in medicine
To replace blood loss during Injury
Some people are giving platelets to help clotting
Proteins extracted from blood can also be used for for example antibodies
What are the problems with blood being donated
In Blood transfusion you have to make sure the donated blood is the same blood type otherwise the bodies immune system would reject the blood and the patient could die
Lots of different diseases can be transmitted by blood

How can you minimize the risk of infections when donating blood
By screening
Humans have a circulatory system. How is the blood pumped
The blood is pumped from the heart to the lungs where is collects oxygen then it returns to the heart and then pumped around the whole body where it delivers the oxygen to the body cells (organs)
What do arteries carry
Very high pressure blood from the heart to the organs in the body
How are arteries adapted to their function
Arteries have thick walls this allows them to carry high pressure of blood
The elastic fibers stretch when the surge of blood passes through and then recoil in between surges which keeps the blood moving
How does blood travel through the arteries
In surges every time the heartbeats
What happens when the blood passes through capillaries
Glucose and oxygen diffuse from the blood to the cells
And
Carbon dioxide diffuses from the cells back to the blood
What’s the structure of capillaries
Capillaries have a thin wall - only one cell thick
They have a very small lumen (The hole down the middle)
They contain nucleus is of cell
What is the structure of veins
They have a very large lumen (The hole down the middle)
They contain elastic fibers and smooth muscles
They contain valves
What is the purpose of valves 
To stop the blood from flowing backwards (When the blood flows forwards the valve opens but if It flows backwards the valve closes)
What is the system for fish for the blood to flow (What is it called)
Single circulatory system (The blood flows slowly)
What are the benefits to a double circulatory system for humans
It can flow quickly delivering oxygen that the cells need
The heart is in Oregon what does it consist mainly of
Muscle tissues
The natural resting heart rate is controlled by what
A group of cells located in the right atrium that act as a pacemaker
What are artificial pacemaker’s
Artificial pacemakers are electrical devices used to correct irregularities in the heart rate
What is a plasma
It is a tissue where all the blood is composed in (Red blood cells, white blood cells, platelets)
Calculate the rate of blood flow
Rate of blood flow = volume of blood flow / number of minutes
Define health
Health is a state of physical and mental well-being
What are major causes of ill health
Both communicable and non-communicable diseases
Other factors including diet, stress and life situations may have an affect on both physical and mental health
Describe the similarities and differences between benign tumors and malignant tumors
benign tumors:
Grows slowly
grows within a membrane
can be easily removed
does not normally grow back
does not spread around the body
can cause damage to organs and be life-threatening
Malignant tumors:
Cancerous
grows rapidly
can spread around the body by the bloodstream
cells can break away and cause secondary tumors to grow in other areas of the body
What happens during coronary heart disease
In coronary heart disease layers of fatty material build up inside the coronary arteries narrowing them. This reduces the flow of blood through the coronary arteries.
What is the effect of not a lot of blood flowing through the coronary arteries
lack of oxygen for the heart muscle
What is the use of stents
It’s a mechanical device which is used to stretch narrow or blocked arteries restoring blood flow (Used to keep the coronary arteries open)
What is the use of statins
Statins is drugs used to lower cholesterol levels in the blood which slows the rate of fatty material disposed
What are the advantages and disadvantages of treating cardiovascular disease by drugs (stains) mechanical devices (stents) or transplant?
Statins:
Can be used to prevent heart disease
improved quality of life
BUT
Possible of negative side effects
Stents:
Made from metal alloys so will not be rejected by the patient’s body
offers long-term benefits
used for patients where drugs are less effective
BUT
Requires surgery which carries risk of infection
Heart transplant:
can treat complete heart failure
artificial plastic hearts can be used temporary until a donor is found
Extended life
BUT
Requires major surgery with risk
Lack of donors
Long recovery time
What types of cancers are there
Lifestyle cancer and genetic cancer
Name some plant tissues
Spongy mesophyll
xylem and phloem
Palisade mesophyll
Epidermal tissues
Meristem tissue found at the growing tips of the shoots and the roots
