Ukraine 11 клас Biology and Ecology
Chapters: 5
1. Adaptations
Adaptation principles · Habitats, symbiosis, parasitism · Biological rhythms
- Adaptation: How a Story Moves from a Book to a Film, Play or Game – An adaptation is a new work made from an older one in a different medium, such as a novel turned into a film, a play, a comic, a series or a game. Each medium has its own tools and limits, so the adapter must cut, merge, change and sometimes add. Adaptations can be faithful, loose or free (transposed to a new time or place). To compare a book and its adaptation, look at what changed, why it changed, and what new meaning it creates.
- Organisms and Populations: Growth and Interactions – A population is a group of the same species living in one area at one time. It has features that a single organism does not have: density, birth rate, death rate, sex ratio and age structure. N grows by births and immigration and shrinks by deaths and emigration. With unlimited food it grows fast (J-curve, dN/dt = rN); with limited food it slows and stops at the carrying capacity K (S-curve, dN/dt = rN(1 − N/K)). Different species affect each other: mutualism (+/+), competition (−/−), predation and parasitism (+/−), commensalism (+/0) and amensalism (−/0).
2. Biological basis of a healthy lifestyle
Healthy lifestyle
- Healthy Lifestyle: Daily Habits That Keep You Well – A healthy lifestyle is a set of daily habits: a balanced diet from five food groups, enough water, 9–11 hours of sleep for school-age children and about 8–10 for teenagers, at least 60 minutes of activity a day, good posture, safe food handling and avoiding tobacco, alcohol and drugs. These habits lower the risk of lifestyle (non-communicable) diseases such as type 2 diabetes, heart disease and some cancers.
3. Ecology
Ecological factors · Populations · Ecosystems and succession · Biosphere
- Ecology Basics: Ecological Factors – Ecology studies how living things and their surroundings affect each other. The surroundings act through ecological factors: non-living (abiotic), living (biotic) and human (anthropogenic). Each species survives in a range of every factor (law of tolerance), and growth is held back by the scarcest factor (law of the minimum). Narrow-range species are steno, wide-range species are eury.
- Organisms and Populations: Growth and Interactions – A population is a group of the same species living in one area at one time. It has features that a single organism does not have: density, birth rate, death rate, sex ratio and age structure. N grows by births and immigration and shrinks by deaths and emigration. With unlimited food it grows fast (J-curve, dN/dt = rN); with limited food it slows and stops at the carrying capacity K (S-curve, dN/dt = rN(1 − N/K)). Different species affect each other: mutualism (+/+), competition (−/−), predation and parasitism (+/−), commensalism (+/0) and amensalism (−/0).
- Ecosystem: Structure, Productivity, Energy Flow and Pyramids – An ecosystem is a working unit of nature where living things (biotic) and non-living things (abiotic) interact. Plants make food at a rate called productivity: gross (GPP) minus respiration gives net (NPP = GPP − R). Dead matter is broken down in five steps: fragmentation, leaching, catabolism, humification and mineralisation. Energy enters as sunlight, flows one way through trophic levels and only about 10% passes on each time. Ecological pyramids of number, biomass and energy show this; number and biomass pyramids can be inverted, but the energy pyramid is always upright.
- The Biosphere – The biosphere is the part of Earth where life exists. It is a thin layer where the geosphere (rock and soil), hydrosphere (water) and atmosphere (air) meet, from about 10 km above sea level to about 11 km below it. It is one huge system made of all ecosystems together. Energy flows through it in one direction, from the Sun to plants to animals and out as heat, while matter such as carbon, water and nitrogen goes round in cycles. Living things also change the other spheres: they make oxygen, build soil and store carbon. Humans now change the biosphere strongly, so we must protect it.
4. Sustainable development and nature use
Pollution and protection · Environmental policy
- Pollution: Air, Water, Land and Noise – Pollution is the release of harmful substances or energy into air, water or land faster than nature can remove them. Main air pollutants are particulates, carbon monoxide, sulfur dioxide, nitrogen oxides and ozone; they cause acid rain and smog. Water pollution by nutrients, sewage and toxins causes eutrophication and biomagnification. We reduce pollution by cutting emissions at the source, cleaning waste before release, and the 3Rs.
- Sustainability – Sustainability means meeting our needs today without taking away the ability of future people to meet theirs. It rests on three pillars — environment, society and economy. A resource is used sustainably when we use it no faster than it renews. Today humanity uses about 1.7 Earths' worth of resources a year, and this use is very unequal. Stewardship, careful planning and spatial tools like GIS help us move towards sustainability.
- Environment and Sustainable Development – The environment gives us resources, soaks up our waste, supports life and gives beauty. When we take resources faster than nature renews them, or throw waste faster than it can absorb, we cross its carrying capacity and face an environmental crisis. India faces land degradation, air and water pollution, forest and biodiversity loss. Burning fossil fuels traps heat and causes global warming; CFCs thin the ozone layer. Sustainable development meets today's needs without harming the ability of future generations to meet theirs, using clean energy, less waste and traditional knowledge.
5. Applied biology: medicine, breeding, biotechnology
Breeding · Biotechnology and biosafety
- Plant Breeding: Making Better Crops – Plant breeding is the purposeful change of crop genes to create better varieties: higher yield, better quality, disease and pest resistance, and tolerance of drought, salt, heat or cold. The oldest method is artificial selection: keep seeds only from the best plants, generation after generation. Hybridisation crosses two parents so the offspring gets good traits from both. Inbreeding (crossing close relatives or selfing) makes pure lines; too much causes inbreeding depression. Outbreeding crosses unrelated lines; the F1 hybrid of two pure lines is often stronger than both parents (heterosis). Interspecific crosses (wheat × rye = triticale) need chromosome doubling. Modern tools: mutation breeding, polyploidy, tissue culture, DNA markers and gene editing. Vavilov showed crops have centres of origin rich in wild relatives, and related species vary in similar (homologous) series.
- Biotechnology and its Applications – The tools of genetic engineering are used in medicine, farming and research. Bacteria make human insulin; yeast makes safe vaccine proteins. Stem cells can become many cell types. Gene therapy puts a correct gene into a patient's cells. GM crops like Bt cotton carry a gene for a protein that kills pests. Transgenic animals carry foreign genes to help study disease or make medicines. Because these are powerful, India controls them through GEAC, and laws guard against biopiracy and unfair patents.