13.1 Plants and People Flashcards
What many key roles do plants have in human society?
provide food, medicines, build materials, and energy
the human food supply is based on the _______ of relatively ___ species of plants
cultivation; few
The use of biofuels has ________________ costs and benefits.
environmental, economic, and social
Plants provide a number of
ecosystem services.
Sustainable development
meets the needs of the present without compromising the ability of future generations to meet their own needs.
true or false: breathing is produced by plants as a waste product of photosynthesis
true
true or false: glues and paints are not plant products
false
why did humans begin to breed plants
to improve food quantity and quality
Over human history, people became more and more dependent on ___________ crops as a source of food.
domesticated
Today, almost all the human food supply is based on the cultivation of only ___ species of plants
14
Canada’s main crops, in order of income generated, are
wheat, canola, barley, corn, soybeans, potatoes, flax, and oats
All fruit and almost all vegetable crops come from ___________ plants, which are the _________
flowering; angiosperms
Corn, rice, wheat, and other cereal grains are the fruits of _________ species
grass
Other foods, such as avocados, lentils, and okra, come from _________ plants.
broad-leaf
The most important crops in the world are _____________, members of the pea and bean family
cereal grains and legumes
_______ is the most common grain in North American and European diets
Wheat
Lettuce, spinach, and tea are
leaves
celery, potatoes, sugar cane, and bamboo shoots are
stems
carrots, sweet potatoes, and beets are
roots
coffee and cocoa are
seeds
spices
strongly flavoured plant parts
Cinnamon is from
bark
vanilla and black pepper are
fruits
cardamom is a
seed
cloves are a
flower
Tasty herbs such as basil, thyme, and mint are the
leaves of aromatic plants
One of the world’s most expensive herbs, saffron, is the ___________ of a crocus flower, collected laboriously by hand
male floral parts
Many of the foods we eat contain __________
hidden processed plant products
examples of hidden processed plant products are
sugars from corn or beets and oil from canola or sunflowers
thickeners, such as guar gum and corn starch, and soy protein is often added to ____________.
increase protein and improve texture
The active ingredient in willow is acetylsalicylic acid, better known as
Aspirin
how does aspirin work
It inhibits the production of prostaglandins, chemicals that increase the pain sensitivity of the body’s nerve endings
taxol
a potent drug used to treat ovarian and breast cancer, was originally derived from the bark of the Pacific yew tree
scurvy
a disease that results from a lack of vitamin C
yield
the amount of an agricultural product that is collected and used by humans
where did fossil fuels come from
Fossil fuels such as coal, oil, and natural gas come from the fossilized remains of plants that died 350 million years ago during the Carboniferous period
Biofuels
Biofuels are energy sources produced from renewable organic materials, including plants and organic waste
how is biodiesel produced
Biodiesel is produced from plant or animal fats or used cooking oil.
Temperate __________, such as beech, oak, and maple, and tropical hardwoods, such as mahogany and teak, are dense woods of _______ used to make high quality furniture and flooring
hardwoods; angiosperms
________ come from ________, which include conifers, such as pine and spruce tree
Softwoods; gymnosperms
ecosystem services
beneficial processes carried out by living things that are necessary to sustain life on Earth
Plant roots _____ soil, reducing erosion in terrestrial ecosystems and coastal areas
bind
Plants are also capable of ______________ toxins and pollutants.
storing or detoxifying
true or false: Some house plants reduce indoor air pollutants
true (spider plant and philodendron)
Trees and other plants in parks and along city streets …
improve air quality, cool the air, reduce storm water runoff, reduce noise levels, and provide habitat for animals
Sustainability
is the capacity to maintain a certain process or state indefinitely
People practising sustainable development can continue to___________, while still protecting biodiversity
farm and harvest timber
In a process called nitrogen fixation…
nodules “fix” the nitrogen that is in the air pockets in the soil, changing it into a form that plants can use
how do maize, beans and squash all benefit from the presence of the others?
The broad leaves of the squash plants shade the soil, maintaining soil moisture and preventing weeds from establishing and competing with the crops. The corn stalks support the climbing stems of the bean plants, while the beans house nitrogen-fixing bacteria in root nodules
kenya sustainable initiatives
In Kenya, farmers are planting weeds in their maize fields to act as “trap plants” for stem borer larvae. Previously, stem borer larvae ate about a third of the maize produced in the region.
However, the larvae prefer to attack napier grass, a local plant often considered a weed. Napier grass secretes a sticky material that glues down and kills the larvae. By planting napier grass among their maize plants, farmers increased maize yield
madagascar sustainable initiatives
a local researcher developed a method to quadruple rice yield. He transplanted the rice seedlings at an earlier stage, delayed flooding of the rice fields, and used locally available compost instead of costly chemical fertilizers
The two main agricultural practices used by Canadian farmers to increase crop yields are the use of
chemical fertilizers and pesticides.
chemical fertilizers
The use of chemical fertilizers, however, releases greenhouse gases and may cause excessive growth of algae if fertilizers run off into lakes or oceans
The two main types of pesticides are
herbicides and insecticides
herbicides
control unwanted plants
insecticides
control unwanted insects
tilling land pros and cons
Tilling land is also done to prepare the soil for crops and to control weeds
increases soil erosion and the loss of soil nutrients. In addition, tilling disrupts wild bees
integrated pest management
pest-management strategies designed to increase crop yields while reducing harmful health and environmental effects. integrated pest management
Crop rotation
Changing the crop grown on a plot of land each year means that each crop is less vulnerable to specialized pests and diseases
Green manure
Growing plants and then tilling them back into the soil increases soil nutrients and improves crop health so they are more resistant to pests.
Planting nitrogen-fixing crops
Growing nitrogen-fixing crops, such as soybean, increases the nitrogen content in the soil, improving crop health.
Biological control
Natural predators, such as birds, ladybird beetles, and spiders, can control some insect pests
Genetically modified crops
Crops can be genetically engineered so they possess desirable traits. For example, Bt corn produces a bacterial toxin that kills the larvae of the corn borer when it feeds on corn.
Pheromones
Pheromones are chemicals used by insects to communicate with one another. Releasing synthetic pheromones may prevent insects from mating or lure them into traps, while not affecting other species.
Canadian farmers use about 9 percent of available water for
irrigating crops
Irrigation reduces ________ because it prevents rich topsoil from drying out and blowing away.
soil erosion
cons of irrigation
may increase the salt content of soil, harming plants. The added water may carry pesticides and fertilizers into ground water, streams, and lakes. If water for irrigation is pumped from underground sources, these sources may not refill
Most Ontario farmers maintain vegetation on the edges of streams or ponds. This vegetation is important because
it prevents soil erosion and reduces water run-off from the farm
sustainable forest management.
Under this policy, forest products are harvested sustainably, preserving the forest’s health and biodiversity.
Canada’s National Tree Seed Centre (NTSC) in Fredericton, New Brunswick …
conserves the genetic diversity of our forests
collects and stores seeds from across the natural ranges of all Canadian tree species.
goal is to obtain a diverse collection of genetic material
Why is canola described as a “made in Canada” plant?
because it was invented in Canada
List the top two economically important crops in Canada and describe their uses
wheat- used domestically for food, feed and fuel
canola- used in cooking oil, animal feed, makex biodiesel to power trucks and heavy machinery which has been proven to reduce greenhouse gas emissions
Name one crop harvested from each plant part: seeds, fruits, leaves, stems, flowers, roots
seeds: coffee
fruit: vanilla
leaves: lettuce
stems: celery, potatoes
flowers: cloves
roots: beets
Poppy (fruit)
drug:
use:
Morphine
codeine Pain killer
Willow trees (bark)
drug:
use:
Acetylsalicylic acid (Aspirin)
Pain killer, anti-inflammatory
Yellowbark cinchona (bark)
drug:
use:
Quinine
Malaria
Why is the destruction of tropical rainforests a threat to human health?
It could be a “medicine chest” of healing plants that will become extinct before they are even discovered
Explain why fossil fuels, such as coal, oil, and natural gas, are plant products
Fossil fuels such as coal, oil, and natural gas come from the fossilized remains
of plants that died 350 million years ago during the Carboniferous period
What are biofuels and how do they differ from fossil fuels?
Biofuels are energy sources produced from renewable organic materials, including
plants and organic waste
when fossil fuels are burned they produce greenhouse gases
What is softwood lumber? Name two products made from softwood lumber
Softwoods come from gymnosperms, which include conifers, such as pine and spruce trees
used for paper and cardboard production
Define the term “ecosystem services.”
beneficial processes carried out by living things that are necessary to sustain life on Earth.
Explain the term “trap plant” and describe an example of how such a plant can increase agricultural yield
In Kenya, farmers are planting weeds in their maize fields to act as “trap plants” for stem borer larvae.
the larvae prefer to attack napier grass, a
local plant often considered a weed.
Napier grass secretes a sticky material
that glues down and kills the larvae.
By planting napier grass among their
maize plants, farmers increased maize yield by nearly 70 percent
Some Aboriginal people of Ontario grew three crops in small fields, which were used for a time and then left fallow.
Explain the significance of these agricultural practices to soil fertility and local biodiversity.
The broad leaves of the squash plants shade the soil, maintaining soil moisture
and preventing weeds from establishing and competing with the crops.
The corn stalks support the climbing stems of the bean plants, while the beans house nitrogen-fixing bacteria in root nodules.
In a process called nitrogen fixation, these nodules “fix” the nitrogen that is in the air pockets in the soil, changing it into a form that plants can use
cons of tilling
Tilling puts air into the soil. This increases bacterial decomposition of organic material in soil and releases carbon dioxide
from bacterial respiration.
Instead of tilling, the farmers plant winter crops or spray biodegradable herbicides
to prepare their fields.
Untilled fields serve as major carbon sinks because organic material in the soil does not degrade and release atmospheric carbon dioxide, a major greenhouse gas
Ontario farmers try to maintain vegetation on the banks of ponds and streams on their farms.
Explain the benefits of this practice
Most Ontario farmers maintain vegetation on the edges of streams or ponds.
This vegetation is important because it prevents soil erosion and reduces water run-off from the farm.
Therefore, it prevents valuable soil,
polluting nutrients, and toxic pesticides from being washed into streams and ponds
Why does the National Tree Seed Centre collect seeds from a variety of trees in each population?
The goal of the Centre is to obtain a diverse collection of genetic material.
Therefore, seeds are collected from many individual trees in each population, not
just from the “best” or tallest trees
