B7 - Further Biology Flashcards
What does synovial fluid do?
Lubricated the joints and cushion the bones
What do ligaments do?
Support joints
What is articular cartilage and what does it do?
Hard, shiny and smooth cartilage that prevents bones from rubbing together
Give two types of joint and an example of each:
Hinge: elbow
Ball and socket: shoulder
What happens to joints with age and what can this lead to? (2;3)
- Cartilage roughens and thins
- Synovial fluid reduces and becomes more viscous
This leads to increased friction, decreased mobility and pain
What is an RSI
Repetitive strain injury
How can a sprain be treated? (5)
Protect Rest Ice - to reduce swelling and pain Compression - to keep the joint in place Elevation - to drain fluid and reduce swelling
How is BMI calculated?
Body mass / ( Height (metres) )^2 squared
What is the limitation of BMI?
•It doesn’t account for muscle and bone density; muscle and bone are more dense than fat
How is maximum heart rate calculated?
220 - your age
Give an example of an antagonistic pair
Triceps and biceps
What type of muscle is the heart and why is this type of muscle special? (2)
The heart is a cardiac muscle so it never fatigues
Why is the left of the heart bigger?
It is more muscular to be able to pump the blood round the whole body
Where does the heart’s own blood supply come from?
The coronary arteries
Name all the parts of the right side of the heart in the order of the blood’s journey : (5)
Vena cava, Right atrium, Valve, Right ventricle, Pulmonary artery
Name all the parts of the left side of the heart in the order of the blood’s journey : (5)
Pulmonary vein, Left atrium, Valve, Left Ventricle, Aorta
Describe the blood’s journey through one circulation: (5)
- Deoxygenated blood from the body enters the right atrium through the vena cava
- It is pumped through the right ventricle then out of the heart to the lungs through the pulmonary artery
- At the lungs, haemoglobin binds to oxygen
- The oxygenated blood returns to the heart through the pulomonary vein to the left atrium
- It is pumped through the left ventricle then out to the rest of the body through the aorta
Why do you think most of the valves in the body are situated in the leg veins?
The legs are under the most pressure against gravity to return blood to the heart
What are the 4 components of blood?
Red blood cells, white blood cells, Plasma and Platelets
What do Red blood cells do and how are they adapted to their job? (1;3)
•They carry oxygen
- Red blood cells have no nucleus so that they can be packed with haemoglobin
- The are smooth so that they can slip along narrow capillaries
- They are bio concave so that they have a large surface area for efficient oxygen uptake
What do white blood cells do? (2)
- Some detect foreign microorganisms and attack them
* Others produce antibodies to destroy foreign cells
What do Platelets do? (2)
- They clot together where skin is wounded
- If blood comes into contact with air, they start a series of reactions and produce protein fibrin which catches and traps red blood cells, making them clot
What does plasma do?
It transports nutrients, antibodies, hormones and waste around the body
What is tissue fluid, where is it found and what does it do?
Tissue fluid is oxygen and nutrient-rich fluid that escapes from capillary walls
Essential foods and oxygen diffuse into cells from the tissue fluid and wastes like CO2 and Urea diffuse into it
What are the three types of blood vessels?
Artery, vein and capillary
What is the job and structure of Arteries? (2)
They carry blood away from the heart. Their walls are thick and elastic to withstand high blood pressures
What is the job and structure of Veins? (3)
They carry blood from the organs. Their walls are thinner and less elastic than that of arteries and they have valves to prevent backflow. They have large lumens.
What is the job and structure of Capillaries? (2)
They connect arteries and veins and allow the exchange of substances between blood vessels and cells.
They have narrow, thin walls, one cell thick
Where is oxygen in the blood taken from and delivered to in the body and why?
Taken from the lungs, taken to all tissues because it is need for respiration
Where are hormones in the blood taken from and delivered to in the body and why?
Taken from the endocrine glands, taken to their target organs because they are needed to control proper organ function
Where is carbon dioxide in the blood taken from and delivered to in the body and why?
Taken from all cells after respiration and taken to the lungs so that it can be removed in exhaled air
Where are food substances and amino acids in the blood taken from and delivered to in the body and why?
Taken from the gut, taken to the liver and other cells to be used for energy and growth
Where are antibodies in the blood taken from and delivered to in the body and why?
Taken from the lymph glands, taken to all tissues to attack foreign cells
Homeostasis
The body’s mechanism for keeping internal conditions constant
What 4 parts make up the body’s system for controlling temperature?
Receptors in the skins, receptors in the blood vessels, the brain, effectors
Hyperthermia
When the body temperature gets too high
Hypothermia
When the body temperature gets too low
What bodily and behavioural methods does a person use to cool down? (4)
Vasodilation, Sweating (heat lost due to evaporation), removal of clothes, moving to a cooler area
What bodily and behavioural methods does a person use to warm up? (5)
Vasoconstriction, increased respiration in the liver, shivering, putting on more clothes, moving to a hotter area
How does shivering warm a person up?
The muscle contractions lead to increased respiration which in turn leads to more heat produced
Below what internal temperature does someone get hypothermia?
34 degrees Celsius
What is a problem with sweating?
It can cause dehydration
Why shouldn’t you give a hot drink to someone with hypothermia?
It would draw cold blood into their core and give them cold shock
Where are Insulin and Glucagon produced?
In the pancreas
What does Insulin do?
Causes glucose to be absorbed from the bloodstream
What does glucagon do?
Causes glucose to be released into the bloodstream
Describe type 1 diabetes: commonness, age group affected, how it affects the body, how is it developed, how it is controlled:
10% of cases of diabetes are type 1, it starts in childhood and the body cannot produce insulin. It is a genetic disease that can be controlled by insulin injections
Describe type 2 diabetes: commonness, age group affected, how it affects the body, how is it developed, how it is controlled:
90% of cases, it starts in middle age and the body doesn’t produce enough/ stops responding to insulin. It is caused by poor, high sugar diet and high body fat percentage. It can only be controlled by good diet and exercise
What are two symptoms of diabetes?
Bloating/ swelling and sweet smelling breath
Simple carbohydrates
Sugars found in processed foods that release sugar quickly
Complex carbohydrates
Sugars found in foods like fruits that release sugar slowly
What is the difference between an open loop and a closed loop system?
Open loop, not all waste is recycled but in a closed loop it is
What are Ecological services ?
Functions provided by ecosystems for all organisms living there
What are the four types of ecological service? And give an example for each
Supporting: Nutrient cycling, oxygen production, pollination, soil protection
Provisioning: Food, Fibre, Fuel and Water
Regulating: Climate regulation, Water purification and Flood protection
Cultural: Education and Recreation
What types of human activity change the inputs of an ecosystem? Give three examples (3)
Using fertilisers, burning fossil fuels and disposal of waste
What types of human activity change the outputs of an ecosystem? Give three examples (4)
Removal of non-recycled waste, harvesting timber, fishing, agriculture
What do trees spikers do?
Hammer nails or spikes into trees in areas where logging is banned to damaged to logging machinery if the trees are logged
Why do some support tree spiking?
It helps prevent illegal logging without damaging the tree
Why do some oppose tree spiking?
It is dangerous and wastes money by damaging good wood, it is illegal so shouldn’t be done some argue
In rainforests, where are most of the minerals contained and why?
In the plants; because of the climate, minerals are taken up very quickly
In temperate forests, where are most of the minerals contained and why?
In the soil; because the climate is cooler, the uptake of minerals and the growth of plants are a lot slower
What is the slash and burn process?
A process of agriculture where trees are cut down and most are burnt but some may be used for timber; this process frees up farmland
What are the problems caused by the slash and burn process? (6)
- it erodes the soil, leading to desertification
- it exhausts the mineral concentration in the soil making it impossible for new plants to grow
- it lowers biodiversity
- it releases large amount of carbon dioxide which contribute towards global warming and cause extreme weather
- it uses up all the ecological services
- it leads to the fragmentation of habitats and extinction of species
How does vegetation protect soil? (3)
- Leaves and stems slow down rainfall so that the rain hits the ground with less force, reducing the likelihood of erosion
- Vegetation acts as a sponge, soaking up water to prevent flooding
- The roots hold soil together
Describe the steps of eutrophication (5)
- Fertilisers contain nitrogen compounds needed for plant growth. When it rains, nutrients leach out of the soil and wash into water systems
- The excess nitrates increase plant growth, especially the rapid growth of algae
- The algae form a blanket at the top of the water, preventing light reaching other plants
- The plants die, the algae continue to use up the oxygen and slowly the water becomes anoxic
- The algae decompose and all species die without oxygen
Anoxic
Without oxygen
Describe the steps of bioaccumulation (4)
- Small amounts of toxic waste may be taken up by plants and attired in their leaves, fruits and flowers
- Animals eat these plants, and as they eat a lot of plants, the amount of chemical stored in their bodies is higher than a single plant
- These animals are eaten by other animals, so their bodies accumulate even higher levels of chemicals
- The animals at the top of the food chain suffer the most due to the increased level of chemicals in their tissues
How does bioaccumulation affect sparrowhawk eggs?
It makes them brittle
Why are microorganisms used to produce complex chemicals? (5)
- simple biochemistry
- they reproduce quickly
- they can make large, complex chemicals from simple ones
- they contain DNA as plasmids for easy modification
- there is no ethical opposition
Why is there a stirrer in a fermenter?
To circulate the oxygen and nutrients evenly
Why is there a cooling water jacket around a fermenter?
To control the temperature
What are some uses of fermenters? (5)
- Microorganisms for antibiotics
- Single cell proteins
- Food production enzymes e.g. Chymosin for cheese
- Enzymes in washing powders to digest stains
- Enzymes for biofuels like ethanol or methane gas
What is recombinant DNA?
A combination of DNA from different sources
What are the two types of vector?
Plasmids and viruses
What are plasmids?
Circular DNA molecules found in some bacteria
What are the 5 steps of genetic modification?
- The desired gene is selected and located and enzymes are used to multiply that gene
- The gene copies are inserted into a suitable vector
- The cave for is allowed to reproduce and is multiplied by more enzymes
- The vectors are inserted into new cells
- The resulting individuals are then filtered to find only the ones showing the modified characteristic
What are the 4 steps of genetic testing?
DNA is isolated from the nucleus of a white blood cell and is broken up into different genes
A gene probe is made to match the gene needed
Mix white blood cells with the probe and the genes will match up with the probe
View cells under a microscope and expose to UV light. If the probe has matched the gene it will glow
What is a DNA probe and why does it only bind to a particular section of DNA?
A DNA probe is an enzyme produced fragment of DNA made to match the section of DNA needed
What are the two ways that nanotechnology is used in the food industry?
Packaging with nanoparticles to prevent oxygen or water from seeping through or silver nanoparticles to stop decay organisms from attacking the food
Biosensors are used in packaging to monitor food quality by detecting harmful microorganisms and changing colour
What are four sources/ types of stem cells?
Embryonic, The organs of a foetus, Adult, Amniotic fluid
What is ethically good about using amniotic fluid stem cells?
The foetus does not die when these are harvested
What are some medical use of stem cells?(5)
Treating leukaemia Burns Blindness Baldness Treating spinal cord injuries
What is leukaemia?
A cancer of the bone marrow that causes the accumulation of diseased white blood cells that attack the body’s own immune system.
Pacemaker
Electrical device that is implanted under the skin to replace the heart’s sinoatrial node to regulate heartbeat
Replacement heart valves
Devices that help the blood flow when one of the heart’s natural valves malfunctions
