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118 Cards in this Set
- Front
- Back
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Why do plant close at night time? |
To protect themselves from bees and to retain water |
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Why is photoperiodism important with plants? |
1) Plant need to germinate 2) Plant growth - more sunlight means more glucose and respiration 3) Plant reproduction - for pollanators |
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What is an anti-herbicide? |
A hormone, released by plants, which releases chemicals that makes insects dislike their taste. |
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What do Melatonin tablets do? |
Induce sleep when the hormone is not naturally released. |
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Why is Melatonin released at the wrong times when you are jet-lagged ? |
Your circadian rhythms are out of place due to the different time zones. |
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What happens in plants when light intensity increases? |
The plants photosynthesise more, meaning more glucose is produced and more respiration can happen |
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Why do plants respire? |
To produce energy for their cells |
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Give an example of a plant defence |
Young Lupin leaves produce alkaloid to protect themselves against insect pests, large herbivores or pathogens. |
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How do we take advantage of plant chemical defences? |
People depend on plants for food so if pathogens destroy/ damage a crop then our food supply is at risk |
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What do potato plants want to kill? |
A fungus-like organism called Potato Blight |
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Name 2 human uses of plant poisons |
1) Digoxin in foxgloves can improve the heart beat 2) Quinine, from the Cinchona plant, can treat malaria |
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Why do we use aseptic techniques? |
To reduce the likelihood of bacteria reproduction/ infection |
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What are the conditions for bacteria to grow? |
Warm, moist, nutrients |
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How does bacteria reproduce? |
By asexual reproduction |
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What is exponential growth? |
The growth rate of a population which is proportional to the populations current value |
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What did Louis Pasteur do? |
1) Showed microorganisms were responsible for some diseases and for food going off. 2) created the aseptic technique of pasteurisation in which foods (such as milk) are heated briefly before being stored to kill bacteria in them |
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How did Louis Pasteur preserve milk? |
In a straight neck flask Pasteur added milk which he boiled for one hour. He found after 4 days the milk had gone off as air and microbes could enter. In a swan neck flask Pasteur added milk which he boiled for 1 hour. He found this milk stayed fresh after 4 days as the microbes could enter but they settled in the bend of the swan neck. |
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Where do hormones travel? |
In the bloodstream |
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What are Blymphocytes? |
White blood cells which respond to vaccines and infections |
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What do antibodies do? |
Stick to the antigen on pathogens. This stops them from replicating and releasing toxins. it immobilisers the pathogen. |
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What are pathogens? |
Microorganisms which cause disease |
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What happens when pathogens multiply inside your body? |
They destroy / damage your cells and some release toxins |
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What do memory lymphocytes do? |
Remain in the body while other antibodies died and are ready to replicate and make clones of each other if the pathogen returns. They replicate faster and make you immune to the pathogens. |
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What do vaccinations do |
Vaccinations trigger the body's immune response to the memory lymphocytes and therefore make you immune to diseases. |
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Why does it take a long time to destroy pathogens in the primary response? |
It takes a long time for the immune system to find the specific antibodies to fit the antigens on the pathogen. |
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Why is the secondary response to infection faster? |
Memory lymphocytes which have remained in the body are ready to replicate when the pathogen returns |
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What do vaccinations contain? |
Dead, weakened, or parts of the pathogen |
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What are the advantages of vaccinations? |
1) You can become immune to the disease without having to suffer from it. 2) Chances of any long lasting harm are much, much less 3) If enough children are vaccinated against the disease, then it becomes so rare that even the unvaccinated individuals are unlikely to get it. |
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What are the disadvantages of vaccinations? |
1) swelling or redness 2) allergic reactions 3) some people may get a mild form of the disease they are being vaccinated against |
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What are monoclonal antibodies? |
Antibodies produced from the same type of lymphocyte. |
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What are monoclonal antibodies used in? |
Pregnancy testing kits, cancer drugs and cancer diagnosis |
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How are monoclonal antibodies made? |
By the Fusion of a blymphocyte from a mouse and a cancer cell to make a hybridoma cells which produces monoclonal antibodies. |
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What are the advantages of hybridoma cells? |
They multiply and divide and manufacture antibodies |
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How do pregnancy tests work? |
As urine diffuses across the stick, the HGH hormone attaches to the antibody and carries the blue pigment to the little window if the woman is pregnant as HGH is produced by pregnant women. |
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How are monoclonal antibodies used in cancer diagnosis? |
Monoclonal antibodies attached to a radioactive isotope. This is put inside the body where it passes through the bloodstream. They attach to cancer cell antigens so you know where the cancer cells are or where a potential blood clot is. |
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How are monoclonal antibodies used in cancer drugs? |
The same method is used as cancer diagnosis but instead of attaching a radioactive isotope you attach a cancer drug. The advantage is it only affects the cancer cells. |
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What is the artery called which brings blood to the kidneys from the heart? |
The renal artery |
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What is a vein called which carries cleaned blood away from the kidneys to the heart? |
The renal vein |
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What does the ureter do? |
Carry urine from the kidney to the bladder. |
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What does the bladder do? |
Stores urine. |
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What does the urethra do? |
Carry urine from the bladder to the outside of the body |
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What are the microscopic tubes inside the kidney called? |
Nephrons |
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What does a kidney dialysis machine do? |
Filter waste products from the blood |
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What are the disadvantages of a kidney dialysis machine? |
1) the machines are expensive. 2) the patient will have to connect to it for several hours, several times a week. 3) The side effects include itchy skin, tiredness and risk of infection |
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What is the structure of a nephron? |
Glomerulus Bowman's capsule Convoluted tubule Loop of Henlé |
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What does the Glomerulus do? |
Filter out big molecules, such as blood cells and protein, so that they don't get into the Bowman's capsule. |
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What passes through the Glomerulus to the Bowman's capsule? |
Small molecules - glucose, salt and water |
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What is selectively reabsorbed into the bloodstream? |
All glucose, no urea and water |
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What is osmoregulation? |
When some water is selectively reabsorbed. |
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Where is the Antidiretic hormones (ADH) released and where does it act upon? |
ADH is released by the pituitary gland in the brain and acts upon the nephron. |
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What happens when more ADH is released? |
There is less urine the bladder, it is more concentrated. |
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What happens when less ADH is released? |
There is more urine in the bladder which is less concentrated. |
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What is ovulation? |
The releasing of the egg. |
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How long does the menstrual cycle last? |
28 days |
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What is oestrogen? |
A hormone produced in the ovaries which causes the lining of the womb to get thicker and it also blocks FSH |
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Where is progesterone released from and what does it do? |
It is released from the corpus luteum and it causes the lining of the uterus to be maintained. It also stops the release of FSH. |
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Where is LH released from and what does it do? |
It is released from the pituitary gland and it tells the ovaries to release the egg into the oviduct. |
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Where is FSH released from and what does it do? |
It is released from the pituitary gland and it's the first hormone to be released. It causes eggs to mature. |
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Which day is ovulation day? |
Day 14 |
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How does the pill work? |
The pill contains high oestrogen and progesterone levels which stops the uterus lining for breaking down so it is maintained. The body thinks it is pregnant so it doesn't release any more eggs. This stops menstruation from occurring and inhibits FSH. |
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What happens when the egg is fertilised? |
The egg implants itself into the uterus lining. The corpus luteum continues to secrete progesterone so the uterus wall remains thick. |
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How does the menstrual cycle demonstrate negative feedback? |
As oestrogen and progesterone levels increase, FSH levels are reduced. |
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What did Edward Jenner do |
He discovered how to make people immune to cowpox by taking pus from a cow pox blister and rubbing it into the skin of James Phipps. James got cowpox but recovered. Then Jenner repeated this again but the boy never got smallpox as he was immune to it. |
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What happens to the egg immediately after fertilization? |
The membrane of the egg changes to stop the entry of other sperm. |
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What type of nucleus does the sperm cell and the egg cell have? |
A haploid nucleus which 1 set of genetic material. |
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What does the acrosome contain? |
Enzymes to digest away into the egg. |
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In fertilisation what is the resulting cell called? |
A zygote which is a diploid and divides repeatedly to form an embryo. |
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What does IVF stand for? |
In Vitro Fertilisation |
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What does a hormone treatment help a woman to do? |
It increases the chance of impregnation as it helps that ovaries to produce more eggs. |
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What is haemophilia? |
Where blood doesn't clot properly. |
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Who was Niko Tinbergen? |
One of the first people to make a scientific study of innate behaviour |
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What is imprinting? |
A Simple Learning during a critical period of an animal's life. |
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What did Konrad Lorenz discover and how did he discover it? |
Lorenz found that birds hatched in an incubator became attached to whatever they say first. It is called imprinting. This is a simple kind of learning which only happens early in animals life during a very short "window" of time. |
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What is the independent variable? |
The variable you change. |
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What is the dependent variable? |
The variable you measure. |
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What are control variables? |
Variables that must be kept the same. |
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What is sensitivity? |
The smallest measurement a piece of equipment can make. |
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What is habituation? |
A simple kind of learning where a response to a stimulus is "switched off" when stimulated frequently. |
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What is classical conditioning? |
The process in which learning cause inate reaction to happen in response to a different stimulus. |
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Explain Pavlov's dogs. |
When a dog sees food salivates. Pavlov rung a bell while the dog ate food. He repeated this process multiple times. Eventually the dogs begin to salivate when it heard the bell. |
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What is operant conditioning? |
A process in which an animal changes it's behaviour as a result of experiencing rewards or unpleasant consequences. |
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How is operant conditioning use on a sniffer dog? |
When the police sniffer dog is being trained it is given an object with a smell to sniff. Then it is presented with several object was various smells. When it indicates the one with the original smell the dog is rewarded. After many repeats the dog learns to search for that particular smell. |
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How is operant conditioning used to train a police horse? |
When the police horse is repeatedly exposed to smoke and finds that nothing bad happens to it it learns not to be afraid of it. |
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How is operant conditioning used to train dolphins? |
A dolphin can be trained to find mines. The dolphin is shown the mine then given a treat. The distance between the mine and the dolphin is increased. When the dolphin find the mine it is given a treat. After many repeats the dolphin learns to search for mines. |
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What different methods of communication do animals used to show their mood or location? |
1) animals can use visual signs such as gestures facial expressions and body language to communicate their mood. 2) sounds can be used to attract other animals or warn them off from territory. 3) many animals produce pheromones which is a chemical substance that diffuses into the air and has an influence on the behaviour of others. |
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What detects the water level in the blood? |
The hypothalamus in the brain. |
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What happens when there's too little water in the blood? |
This is detected by the hypothalamus in the brain and pituitary gland secretes more ADH and more water is selectively reabsorbed meaning there is less urine in the bladder. The blood plasma concentration goes back to normal. |
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What happens when there is too much water in the blood? |
The hypothalamus in the brain detects this and the pituitary gland secretes less ADH so Les water is selectively reabsorbed and there is more urine in the bladder. The blood plasma concentration goes back to normal. |
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What is negative feedback? |
A control mechanism in which a change in a factor causes an action that reverses the change. |
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What can cause a rise in the water content in the blood? |
Drinking water or a drink and eating food. |
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What can cause a fall in the water content in the blood? |
Exercising and sweating. |
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What is coevolution? |
A change in a genetic composition of one species in response to a genetic change in another. |
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Tell me about Ardi. |
Ardi dates back to 4.4 million years ago. Her brain size is roughly 250cm cubed. She uses no tools. She is 120 cm tall approximately and weights 50 kg. She walks upright and has long arms and big toes. |
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Tell me about Lucy |
Lucy dates back to 3.2 million years ago. Her brain size is 400 cm cubed. She uses no tools. She is 1.07 m tall, has long arms and doesn't walk complete upright. |
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What factor affects the pH level of yoghurt? |
The enzymes break down there lactose, in anaerobic conditions, in the milk. This turns into lactic acid which brings down the pH level. |
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What happens after the optimum pH or temperature? |
Enzymes denature and no longer work on the substrate they are designed for. |
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What animal did Dian Fossey work with and what did she do? |
She worked with mountain gorillas. She found that by imitating their behaviour towards each other she was partly accepted into their group Overall she discovered that they had complex family relationships. |
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What animals did Jane Goodall work with and what did she discover? |
She worked with chimpanzees and discovered by working closely with chimpanzees the chimpanzees make and use tools to help them get food. She also discovered that they hunt in groups. |
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Why is mtDNA better than nuclear DNA for tracing genetic inheritance? |
It decays slowly therefore when you find it it is more likely to be in a good condition to identify the genetic sequence. Also there is more of it so you're more likely to get a good sample of it from fossil remains. |
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How might have climate change helped early humans cross the Bering Sea? |
When the climate became cold they entered a glacial environment. The Sea froze meaning our ancestors could walk across the frozen sea to different land as the sea levels fall. |
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Give examples of food made using microorganisms |
Yoghurt, bread, wine, cheese, Quorn |
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What is biotechnology? |
The alteration of natural biomolecules using science and Engineering to provide goods and services. |
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What is a fermenter? |
A vessel used to cultivate microorganisms for the production of biomolecules on a large scale. |
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What are the advantages of using microorganisms for food production? |
1) the population of microorganisms can double in number in 20 minutes. 2) they are grown in fermenters rather than taking up space in fields. 3) production is independent of climate meaning it can be grown anywhere in any conditions 4) fusarium which is used to make mycoprotein is a waste product from other industrial processes. |
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How is mycoprotein made? |
Fusarium is made up of tiny fibres called hyphae. The hyphae are collected and heat-treated to remove bitter tasting substances. The mixture is not stirred because this would tangle and break the fibres .They are dried and pressed to form a fibrous substance. |
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What are the advantages of using mycoprotein as a food source? |
1) It contains no saturated fat that could lead to heart disease 2) It has a high protein content (48 grams per 100 grams of mycoprotein) 3) It has a high fibre content which slows the rate at which glucose is a absorbed 4) It has a high carbohydrate content |
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What are enzymes? |
Proteins, produced by living organisms, that act as catalysts. |
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Explain the effect of enzymes yoghurt making |
The enzymes break down the lactose in anaerobic conditions in milk this turns into lactic acid which brings down the pH level. |
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Why are immobilised enzymes less affected by temperature? |
The enzymes are less likely to be denatured because of the protective layer. |
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What breaks down the pectin in the cell wall of fruit? |
Pectinase breaks down the pectin in the cell wall and turns it into juice. It digest the cell wall and the juice is released. |
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How does the Peacock attract the female? |
By showing it's colourful feathers |
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How does the rifle bird attractive the female? |
He dances and swings his head to show her his strength then he envelopes her and they reproduce. |
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How does the Manatin attract the female? |
Pre dance he's clears his performance space so that it is tidy. The Manatin does a "moonwalk" dance for the female. |
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What enzyme breaks down fat into glycerol and fatty acids? |
Lipase |
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Where is lipase found? |
In the small intestine |
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What enzyme break down carbohydrates? |
Carbohydrase |
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What enzymes break down protein? |
Protease |
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What is Chymosin and what does it do? |
Chymosin is an enzyme from the calves stomach. It is added to milk and affects the protein in the milk making the milk separate to curds and liquid whey. |
