Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
UNIT 2 BIO e.r
Unit 2 exam revision YR 11 Biology
| Question | Answer |
|---|---|
| 1. Describe 3 ways in which animals obtain water. | Food, free water, metabolic water (water produced from reactions in the body) |
| 2. Describe 3 ways by which animals lose water. | - Urination - Perspiration - Breathing - Faeces |
| 3. What is the external and internal environment of a person? | External is outside environment (e.g. air temp, windy or still day). Internal is the body’s inside environment (e.g. oxygen levels in blood, core body temp, pH levels of any fluid) |
| 4. Define homeostasis. | Homeostasis is how the body keeps conditions inside it the same. (stable internal environment) |
| 5. What two body systems contribute to homeostasis? | The Nervous System and the Endocrine System |
| 6. What are the two main parts of the nervous system? | - the central nervous system (CNS) - peripheral nervous system (PNS) |
| 10. What does an interneuron do? | relay signals between motor and sensory neurons. |
| 11. What is a reflex arc and why are they important for survival? | 11. Simple pathway taken by nerve messages that results in an involuntary movement. The resulting movement often removes a person from a dangerous situation, hence it is important for survival. |
| 12. Describe what happens when you step on a pin. | 12. Sensory neuron detects that you’ve stood on something sharp and sends message to CNS (spinal cord). CNS sends message to a motor neuron which sends it to the leg muscle so that it moves off the pin. It is only then that the brain registers pain. |
| 13. What is a hormone and where are they produced? | A chemical compound that travels through the blood to exert an effect on a target compound |
| 14. What is a negative feedback loop? | it ensures that, in any control system, changes are reversed and returned back to the set level. |
| 15. What two hormones are involved in controlling our blood sugar levels and where are they produced? | Insulin and glucagon are the hormones that control blood sugar levels in the body. It is produced by the isles of Langerhans in the pancreas. |
| 16. Explain what happens when our blood glucose levels are too high? Use the terms receptor, effector and response in your answer. | Insulin is secreted into the blood – the liver converts glucose into glycogen – it then goes down |
| 17. What happens when our blood glucose levels are too low? | Glucagon is released from the pancreas. Travels to the liver where it converts glycogen to glucose. Glucose is then released into the blood to increase the levels. |
| 18. Explain why diabetics have to take insulin injections. | 18. Diabetics do not produce insulin. They therefore have to take injections of it as low levels of insulin can lead to many complications. |
| 19. When should such injections be taken and why? | Before meals. Insulin travels in the blood so it takes time to reach the muscle cells. If it was taken after a meal, there wouldn’t be enough insulin circulating in the blood in time for the muscles to take up the glucose that is consumed in the meal. |
| 20. List and describe four ways by which mammals may lose heat energy to their environment. | Convection, conduction, radiation and evaporation |
| 21. What should your core body temperature be? Which gland in the brain regulates body temperature? | 37 degrees. Hypothalamus |
| 22. Explain how shivering acts to warm the body up when it gets too cold. | Signals various muscles to ‘shiver’, which produces heat and acts to increase body temperature. |
| 24. What behavioural changes might a person make to keep warm? | Jumping around, putting more clothing on, staying inside, going for a run |
| 25. Explain how sweating and vasodilation act to cool the body down when it gets too hot. | Vasodilation: The heart rate would decrease as the blood vessels increase in diameter causing the blood pressure to fall back to its normal range Sweating: Stimulation of glands that produce sweat to reduce the temperature |
| 26. What behavioural changes might a person make to keep cool? | Take clothes off, swim in cool water, |
| 27. Some animals pant rather than sweat. Explain how panting reduces an animal’s body temperature. | The major blood vessel in a dog's head runs very close to the surface of its nose. The fresh air a dog breathes when panting works like a fan to cool the blood in the snout, which then circulates to cool the rest of the pup. |
| 28. How does surface area affect how much heat is gained or lost from the environment? | 28. Large animals have a small surface area:volume ratio so therefore lose less heat to the environment than small animals that have a large surface area:volume ratio |
| 29. Why are animals in the Antarctic much bigger than those in warmer climates (think of the Emperor penguins)? | 29. Emperor penguins are large so have a small surface area compared to their volume so they don’t lose as much heat to the environment. This is important in the Antarctic so that they keep in as much heat as possible. |
| 30. What is the difference between a physiological, behavioural and structural adaptation? | Physiological adaptation – a feature that works involuntarily- vasodilation). Behavioural adaptation – something you do in a particular situation (you control it) Structural adaptation- size/shape of a body part.-large ears in desert rabbits |
| 31. What is the difference between an endothermic and ectothermic animal? Give an example of each. | 31. Endothermic animals can control their internal body temperature so that it stays constant (e.g. humans). The internal temperature of ectothermic animals changes with the external environment (e.g. reptiles) |
| 32. What is transpiration? | The loss of water from a plant |
| 33. Through which part of a plant does most water loss occur? | Stomata (pores in the leaves) |
| 34. The stomatal pores of a plant need to be open for what to enter the plant? What is a problem for the plant when the pores are open? | 34. Pores need to be open to allow carbon dioxide to enter so that photosynthesis can occur. Problem with this is that water leaves the plant through these pores and the plant can become dehydrated. |
| 35. Does transpiration increase or decrease on a windy day? Explain your answer. | Transpiration is faster in windy conditions - Water vapour is removed quickly by air movement, speeding up diffusion of more water vapour out of the leaf |
| 36. Does transpiration increase or decrease on a humid day? Explain your answer. | Transpiration is slower in humid conditions - Diffusion of water vapour out of the leaf slows down if the leaf is already surrounded by moist air. |
| 37. Does transpiration increase or decrease on a hot day? Explain your answer. | Transpiration is faster in higher temperatures - Evaporation and diffusion are faster at higher temperatures |
| 38. Describe the difference between an innate and a learned behaviour. | Innate behaviour is that that an organism is born with and learned behaviour is that that an organism acquires, or develops over their lifespan |
| 39. What are the 5 types of learned behaviours | Imprinting, Habituation, Conditioned Behavior,Trial and Error Learning, Insight learning |
| 40. What is territorial behaviour and why do some animal exhibit it? Give an example of territorial behaviour. | Territorial behaviour is behaviour associated with defending an area against other individuals, usually of the same species – defending young and mate from other competitors or predators |
| 41. What is a tropism? Explain the difference between a negative and positive tropism. | the growth of a plant in response to a stimulus. A positive tropism is the growth of a plant towards the stimulus. Negative is the growth of a plant away from the stimulus. |
| 42. Define the terms phototropism and geotropism. | geotropism: response of a shoot or root to gravity phototropism: movement of a plant in response to light |
| 43. Explain how a plant bends towards light. Why do they need to do this? | Light causes auxins (growth hormones) to move towards the dark side of the plant. This side of the plant grows faster than the other side. Plants need to grow towards light so they can use it to undergo photosynthesis. |
| 44. Explain how the roots and shoots of a seedling buried underground grow down and up respectively. Does the growth of the root show negative or positive geotropism? | Auxins cause the shoot to bend upwards and out of the soil to reach sunlight. The auxins that accumulate on the lower side of the root are growth inhibiting. , causing the roots to bend down into the soil to gain nutrients and water |
| 45. Define the term sexual reproduction, | when two individuals produce offspring that have genetic characteristics from both parents- Introduces new gene combinations in a population. |
| 46. Explain the terms monogamy and polygamy as it refers to animals and give an example of an animal for each. | Monogamy: The exclusive mating of a one male and one female. Polygamy: The mating of one male with more than one female during the course of a mating season. |
| 47. What is r-selection and K-selection. Give an example and advantage and disadvantage of each. | R= Quick-and-many:are produced in large numbers but they have high mortality rates so that few survive to adulthood. K= Slower-and-fewer: mature slowly, breed later, produce fewer and larger offspring and may put extensive parental care into offspring. |
| 48. Explain the terms viviparity and oviparity. | those that give birth to live young. The young develop within the mother's body. |
| 49. What differences are seen in plants that are wind-pollinated and insect-pollinated? | Insect-large, brightly coloured petals - to attract insects, often sweetly scented - to attract insects, usually contain nectar - to attract insects, pollen often sticky or spiky. Wind-small petals, often brown or dull green - no scent - no need to attrac |
| 1. What is an ecosystem? | An ecosystem is a community, physical structures in the environment and the relationship between the two |
| • habitat | Where animals live at a given time |
| • microhabitat | The smaller more select habitat within a habitat |
| • biotic | All living organisms |
| • abiotic | Non-living – oxygen, minerals, water etc. |
| • tolerance range | The range in which an organism can withstand while surviving in their environment |
| 3. Give some examples of biotic and abiotic factors in a pond ecosystem. | Biotic factors such as frogs and small fish – Abiotic factors such as minerals in the water, oxygen in the air etc |
| 4. What happens if an organism lives in a habitat where an environmental factor may be above or below its tolerance range? Give 3 examples of what these environmental factors could be. | Can cause death of the species. Examples are extremes of temperature, pH and oxygen levels. |
| 5. Explain the difference between a population and a community? | Population describes on species only whereas a community describes many species living together |
| 6. Describe the difference between the 2 main forms of energy found within an ecosystem | Radiant energy – energy from the sun and Chemical energy – what radiant energy is converted into |
| 7. In every ecosystem there are producers. What is another word for producers and why are they important in an ecosystem? By what process do they obtain energy? | Autotrophs. Get their energy (glucose) from sunlight (photosynthesis). |
| 8. What is another word for consumers in an ecosystem? How do they obtain energy? | Heterotrophs. Eat food to obtain glucose (energy). |
| 9. Name the 4 types of consumers and give an example of each. | 9. Herbivores (eat plants, e.g. insects). Carnivores (eat meat e.g. lion) Omnivores (eat both plants and meat e.g. crows). Detritivores (eat decomposing matter e.g dung beetle). |
| 10. What are decomposers and what is their role in an ecosystem? | Are fungi and bacteria that get their energy from decomposing matter. They are different to detritivores because when they feed off the decomposing matter, they also break down some of it and send the nutrients back to the environment |
| • Predator/prey | Predator hunts down the prey and is in dominance the prey suffers no benefit |
| • Parasite/host | Parasite lives of the host at the hosts’ expense |
| • Mutualism | Is when both organisms benefit |
| • Commensalism | Is when one organisms benefits and the other is at no harm nor is benefitted |
| 12. What does a food web show? What do the arrows indicate? | A food web shows the energy flow within an ecosystem and whom eats whom, The arrows indicate the direction of energy flow |
| 14. What are primary, secondary and tertiary consumers in a food web? What type of consumers are they? | Primary consumers are herbivores that feed off producers Secondary consumers are carnivores that feed on primary consumers - carnivores Tertiary consumers are organisms that feed only on carnivores - carnivores |
| 15. How much energy is passed on to species at each successive trophic level in a food web from the previous level? | 10% |
| 16. What is an ecological niche? | It is a specific position or role taken by a kind of organisms within its community. Antelopes in Africa and kangaroos in Australia for example |
| peripheral nervous system | PNS = neurons (nerve cells) |
| central nervous system | CNS = brain and spinal cord. |
| Explain vasoconstriction in cold weather | Blood vessels constrict, the flow of blood is restricted or decreased, which acts to retain body heat or increase vascular resistance |
| Explain piloerection in cold weather | Hair follicles stand upright by contraction of erector pili, forming an insulating layer known as goose bumps. |
| Explain thyroxine in cold weather | Thyroxine is a hormone released which speeds up cell metabolism. A by-product of this is the generation of heat which warms us up. |
| Define the term asexual reproduction | : when one individual produces offspring that are genetically identical to itself. These offspring are produced by mitosis. |
| Define the term hermaphrodite | An organism that is neither male nor female - it has both male and female sex organs. |
| Define the term parthenogenesis | : A type of asexual reproduction in which a female gamete or egg cell develops into an individual without fertilization. |
| Explain the terms oviparity. | animals produce eggs, but instead of laying the eggs, the eggs develop within the mother's body. |
| Imprinting (learned behaviour) | learning that occurs only during a restricted time period called the critical learning period. Once learned, it is not forgotten (e.g., ducklings will imprint most strongly on moving (and calling) |
| Habituation (learned behaviour) | learning not to respond to meaningless stimuli (e.g., birds nesting near highways learn not to respond to traffic noise). |
| Conditioned behaviour (learned behaviour) | involves attaching a pre-existing response to a new or substitute stimulus (e.g., Pavlov's Dog). |
| Trial and Error learning (learned behaviour) | involves modifying response to stimuli or creating new responses (e.g., learning palatable and unpalatable foods) |
| Insight learning (learned behaviour) | production of a new response upon reorganization of experience (commonly referred to as insight or understanding) |
Created by:
amygibbo72
Popular Biology sets