How do different substances support or

harm living things?

Organic & Inorganic Substances

• chemicals are part of EVERYTHING• all living things need chemicals and

produce them• chemicals are classified as organic or

inorganic

Inorganic Chemicals

• elements/compounds found in nature

• not combined with carbon (but may be C

alone)

• come mainly from the soil (some from

air)

• fertilizers are added to soil to improve nutrients Nitrogen Phosphorus

Potassium Calcium

Magnesium Sulfur

What’s important to a plant?

Fruits & Grains (sulfur)

Chlorophyll

(potassium, magnesium &

nitrogen)

Photosynthesis(phosphorus & magnesium)

Leaves & Stems

(potassium & nitrogen)

Flowers (phosphorus)

Roots (phosphorus)

Cell Structure(calcium)

Resistance to Disease & Starch

Production

(potassium)

Bones & Teeth

Calcium

Magnesium

Phosphorus

Nitrogen

Potassium

Calcium

Muscles Blood

Calcium

Nervous System

Potassium

Calcium

Body Functions

Nitrogen

Phosphorus

Sulfur

What’s important to us?

Nutrient Importance in PLANTS

Importance in HUMANS

Nitrogen Nitrogen

(N)(N)

- in chlorophyll & proteins - helps leaf and stem growth

- in proteins & nucleic acids - helps growth and repair of body tissue

Phosphorus Phosphorus

(P)(P)

- in root and flower growth - helps cellular respiration & photosynthesis

- in bones, teeth & DNA - helps metabolic reactions

Potassium Potassium

(K)(K)

- helps early growth, chlorophyll production, starch production, and resistance to disease

- helps muscle contraction & nerve impulses

Magnesium Magnesium (Mg)(Mg)

- helps chlorophyll structure & photosynthesis

- in bones & teeth

Calcium Calcium

(Ca)(Ca)

- helps cell wall structure & cell division

- in bones & teeth - helps blood clotting and muscle & nerve function

Sulfur Sulfur

(S)(S)

- helps production of fruits grains

- helps protein synthesis, enzyme activation and detoxification

It’s a Balancing Act

• we must get just the right amount of inorganic chemicals– to much or to little can be harmful

• macronutrients (>100 mg/day)e.g. nitrogen, calcium, potassium

• micronutrients (< 100 mg/day)

e.g. zinc, iron, boron

Organic Chemicals

• carbon combined with other elements

• building blocks for life• 4 elements are most common

Synthesizing Organic Substances

• plants & animals can create some of the organic substances needed for life

made up of building blocks called amino acids

10 essential amino acids must be ingested every day (they are not stored)

What About Vitamins?

• large organic molecules that help enzymes function

C

B’s

ED

A

How do we take in substances?

• Uptake by Plants– through roots (passive or active)

– diffusion → water & nutrients flow from higher concentration (in soil) to lower concentration (in roots)

– active transport → plant really needs a nutrient and so “sucks” it in from surrounding soil moisture (nutrients go from area of lower concentration in soil to higher

concentration in roots)

• Uptake by Animals– we eat, drink and breath

– ingestion: the process to taking in food• food is chewed and then digestion is helped

by enzymes in mouth, stomach & small intestine

– hydrolysis: a special process• large organic molecules (like starch) are

broken down by reacting with water

– nutrients are absorbed through cell membranes and then transported by blood to

where they are needed

Substrate and Nutrient Sources

• organisms get nutrients from environment(s) in which they live

• substrate is the material on which an organism moves or lives– attach to substrate– live off substrate– move over/through substrate

What about Chemicals?

• living things depend on chemicals to survive– photosynthesis is used by plants to

create food– cellular respiration is used by plants and

animals to provide energy from food

• but not all chemicals are good

Pollution

• fertilizer– to much or wrong

place

• pesticides– insecticide– herbicide– fungicide

• solid & liquid waste– landfill– water treatment

• air emsission– combustion– incineration

any accumulation of unwanted waste matter in the environment(natural or man made)

Bioaccumulation & Biomagnification