ISB 201 Unit 3 study guide

what makes soil healthy?

nutrients, minerals, biotic communities, proper ph, soil texture

too much clay in soil

does not allow water and gas exchange

too much sand in soil

does not hold water and nutrients

compaction

this can affect water and gas exchange by making the soil impermeable

what is soil

a complex ecosystem of living and non living things that occur on the land surface and is characterized by the ability to support rooted plants

what is an ecosystem

a community of living organisms and their associated non living ecosystems

what is a biosphere

the part of earth that contains all ecosystems

what is a community

populations that live together in a defined area

what is a population

group of organisms of one type that live in the same area

what is an organism

individual living thing

where do nutrients in soil come from

the decomposition of dead plants and animals

how do lichens help produce soil

1.small roots penetrate and crack rock surfaces creating small mineral deposits (physcial breakdown)

2. acidic secretions from lichen dissolve rock surfaces releasing mineral deposits (chemical breakdown)

3. part of the lichen dies annually and the fungus component breaks down and releases basic nutrients

what is erosion and transport

erosion is the breakdown of rock and soils, transportation is the movement of the material

examples of ecosystem services provided by soil

habitat for plants and animals, aids decomposition of organic matter, provides nutrition to support food webs, assists with water purification, degrades contaminants

what is bioremediation

the process of using living organisms (microbes) to return environments altered by contaminants to original conditions

examples of bioremediation

oil spill cleanup, wastewater treatment, landfill cleanup, heavy metal cleanup, industrial waste cleanup

micronutrients

needed in small amounts

macronutrients

needed in large amounts

examples of micronutrients

iron, magnesium, copper, zinc, boron, chloride, molybdenum

what do humans require iodine for

development of the fetus, breast milk production, thyroid hormones, evey gland uses iodine, lack of iodine linked to breast cancer

what is the importance of nitrogen

required by animals and plants, important in building cell structure, builds lipids, proteins, and carbohydrates, 3% of our total body weight is nitrogen

how do we acquire our nitrogen

meat, fish, dairy, legunes

what do humans need phosphorus for

structure of dna, healthy bones and teeth

what do plants require phosphorus for

structure of dna and cell walls, role in photosynthesis

how do we require phosphorus

through our diet similar to nitrogen

what does magnesium promote

absorption and metabolizing of other minerals, including sodium, potassium, phosphorus, and calcium. this means magnesium is crucial for proper hydration, acid alkaline balance, and muscle contractions including the heart

what is selective breeding

the process of (humans) choosing specific plants or animals to reproduce to generate offspring with desirable traits

what is genetic modification

(humans) take the dna from one organism and inserting it into the genome of a different organism using invasive techniques

what are broad spectrum pesticides

developed to kill a broad range of insect pests to promote greater output of agriculture

what are the economical benefits of broad spectrum pesticides

effective, persistent, cheap

what is the most used broad spectrum pesticide

arsenic

how was DDT used during WWII

sprayed barracks, bedding for bed bugs (prevent sleep deprivation) dusting soldiers, dusting civilians for body lice (prevent typhus) near military bases for mosquitos (prevent malaria, dengue fever)

what is biomagnification

the process whereby certain substances, such as pesticides or heavy metals, become concentration in tissues of organisms and becomes more concentrated as you move up the food chain

what is bioaccumulation

the absorption and increase in concentration in organisms over time (this refers to the accumulation of a chemical/toxin in one individual)

what is a pesticide treadmill

the continued or increased use of pesticides with no end in sight, due to the development of pesticide resistance traits in pest populations

what is integrated pest management

a sustainable approach to pest control that combines multiple management strategies to minimize the use of pesticides

examples of pesticides

gmos, biological control, beetles banks, trop crops, crop rotation