Technology and behavior help people live in most places on Earth. Some people live on the cold Arctic tundra. Others live in hot and humid rainforests.
Still others live in hot and dry deserts. We can live almost anywhere! Plants and animals are adapted to live in specific environments. They need certain temperatures to survive. Plants need the right amounts of rain and sunlight. They depend on their environment to be just right for them. You can learn more about plants and their needs by visiting a conservatory. This is a place where plants are grown and displayed.
At the Franklin Park Conservatory in Columbus, Ohio, you can see over plants from all over the world. Are you ready to take a little tour? Plants that live in this environment are adapted to live in cool temperatures.
They can grow in rocky soils and survive in strong winds. As soon as you walk into the next room, you know where you are. The air is hot and humid and huge plants are growing everywhere. These plants need warmer temperatures and lots of rainfall to survive. Walk through another door and into the desert! In fact, the air is dry. You see cacti and other plants that are well suited for life with extreme temperatures and little water.
Finally, a short walk takes you to the Pacific Islands room. Like the tropical rainforest, this room is warm and humid. Gigantic ferns grow here. So do palm trees and other plants that like rain and warm weather. These plants can grow in the conservatory because the rooms are like their natural environments. The people who work there keep the rooms at the right temperature. They make sure the plants get the right amount of water. Now you know how plants are adapted to their environments.
What about animals? What animals might live in each of these four environments? How would they be adapted to live there? Access this Grades text as a text-only document. Access this Grades text as a full-color illustrated book. Access this Grades text as an electronic book. This article was written by Jessica Fries-Gaither. She has taught in elementary and middle school settings. Three principal characteristics of light affect plant growth: quantity , quality , and duration.
Light quantity refers to the intensity, or concentration, of sunlight. It varies with the seasons. The maximum amount of light is present in summer, and the minimum in winter. Up to a point, the more sunlight a plant receives, the greater its capacity for producing food via photosynthesis. You can manipulate light quantity to achieve different plant growth patterns. Increase light by surrounding plants with reflective materials, a white background, or supplemental lights. Decrease it by shading plants with cheesecloth or woven shade cloths.
Light quality refers to the color wavelength of light. Sunlight supplies the complete range of wavelengths and can be broken up by a prism into bands of red, orange, yellow, green, blue, indigo, and violet. Blue and red light, which plants absorb, have the greatest effect on plant growth.
Blue light is responsible primarily for vegetative leaf growth. Red light, when combined with blue light, encourages flowering. Plants look green to us because they reflect, rather than absorb, green light. Knowing which light source to use is important for manipulating plant growth.
For example, fluorescent cool white light is high in the blue wavelength. It encourages leafy growth and is excellent for starting seedlings. Incandescent light is high in the red or orange range, but generally produces too much heat to be a valuable light source for plants. Fluorescent grow-lights attempt to imitate sunlight with a mixture of red and blue wavelengths, but they are costly and generally no better than regular fluorescent lights.
Duration, or photoperiod , refers to the amount of time a plant is exposed to light. Photoperiod controls flowering in many plants Figure Scientists initially thought the length of light period triggered flowering and other responses within plants.
Thus, they describe plants as short-day or long-day, depending on what conditions they flower under. We now know that it is not the length of the light period, but rather the length of uninterrupted darkness, that is critical to floral development. Plants are classified into three categories: short-day long-night , long-day short-night , or day-neutral, depending on their response to the duration of light or darkness.
Short-day plants form flowers only when day length is less than about 12 hours. Many spring- and fall-flowering plants, such as chrysanthemum, poinsettia, and Christmas cactus, are in this category.
In contrast, long-day plants form flowers only when day length exceeds 12 hours. Most summer flowering plants e. Day-neutral plants form flowers regardless of day length. Examples are tomato, corn, cucumber, and some strawberry cultivars. Some plants do not fit into any category, but may respond to combinations of day lengths. Petunias, for example, flower regardless of day length, but flower earlier and more profusely with long days.
You can easily manipulate photoperiod to stimulate flowering. For example, chrysanthemums normally flower in the short days of spring or fall, but you can get them to bloom in midsummer by covering them with a cloth that completely blocks out light for 12 hours each day. After several weeks of this treatment, the artificial dark period no longer is needed, and the plants will bloom as if it were spring or fall.
This method also is used to make poinsettias flower in time for Christmas. To bring a long-day plant into flower when day length is less than 12 hours, expose the plant to supplemental light. After a few weeks, flower buds will form. Temperature influences most plant processes, including photosynthesis, transpiration, respiration, germination, and flowering.
As temperature increases up to a point , photosynthesis, transpiration, and respiration increase. When combined with day-length, temperature also affects the change from vegetative leafy to reproductive flowering growth.
Depending on the situation and the specific plant, the effect of temperature can either speed up or slow down this transition. The temperature required for germination varies by species. Generally, cool-season crops e. Sometimes horticulturists use temperature in combination with day length to manipulate flowering. For example, a Christmas cactus forms flowers as a result of short days and low temperatures Figure If temperatures are high and days are long, cool-season crops such as spinach will flower bolt.
However, if temperatures are too cool, fruit will not set on warm-season crops such as tomato. Low temperatures reduce energy use and increase sugar storage.
Thus, leaving crops such as ripe winter squash on the vine during cool, fall nights increases their sweetness. Adverse temperatures, however, cause stunted growth and poor-quality vegetables.
For example, high temperatures cause bitter lettuce. Thermoperiod refers to daily temperature change. Plants grow best when daytime temperature is about 10 to 15 degrees higher than nighttime temperature. Under these conditions, plants photosynthesize build up and respire break down during optimum daytime temperatures and then curtail respiration at night.
However, not all plants grow best under the same range between nighttime and daytime temperatures. Temperatures higher than needed increase respiration, sometimes above the rate of photosynthesis.
Thus, photosynthates are used faster than they are produced. For growth to occur, photosynthesis must be greater than respiration. Daytime temperatures that are too low often produce poor growth by slowing down photosynthesis. The result is reduced yield i.
Some plants that grow in cold regions need a certain number of days of low temperature dormancy. Knowing the period of low temperature required by a plant, if any, is essential in getting it to grow to its potential. The cold temperature allows the bulbs to mature. When transferred to a greenhouse in midwinter, they begin to grow, and flowers are ready to cut in 3 to 4 weeks. Plants are classified as hardy or nonhardy depending on their ability to withstand cold temperatures.
Hardy plants are those that are adapted to the cold temperatures of their growing environment. Woody plants in the temperate zone have very sophisticated means for sensing the progression from fall to winter. Decreasing day length and temperature trigger hormonal changes that cause leaves to stop photosynthesizing and to ship nutrients to twigs, buds, stems, and roots. An abscission layer forms where each petiole joins a stem, and the leaves eventually fall off.
Changes within the trunk and stem tissues over a relatively short period of time "freeze-proof" the plant. Winter injury to hardy plants generally occurs when temperatures drop too quickly in the fall before a plant has progressed to full dormancy. Text on this page is printable and can be used according to our Terms of Service. Any interactives on this page can only be played while you are visiting our website.
You cannot download interactives. Freshwater is a precious resource on the Earth's surface. It is also home to many diverse fish, plant, and crustacean species. The habitats that freshwater ecosystems provide consist of lakes, rivers, ponds, wetlands, streams, and springs. Use these classroom resources to help students explore and learn about these places. A limiting factor is anything that constrains a population's size and slows or stops it from growing. Some examples of limiting factors are biotic, like food, mates, and competition with other organisms for resources.
Others are abiotic, like space, temperature, altitude, and amount of sunlight available in an environment. Limiting factors are usually expressed as a lack of a particular resource. For example, if there are not enough prey animals in a forest to feed a large population of predators, then food becomes a limiting factor.
Likewise, if there is not enough space in a pond for a large number of fish, then space becomes a limiting factor. There can be many different limiting factors at work in a single habitat, and the same limiting factors can affect the populations of both plant and animal species.
Ultimately, limiting factors determine a habitat's carrying capacity, which is the maximum size of the population it can support. Teach your students about limiting factors with this curated collection of resources. A biome is an area classified according to the species that live in that location. Temperature range, soil type, and the amount of light and water are unique to a particular place and form the niches for specific species allowing scientists to define the biome.
However, scientists disagree on how many biomes exist. Some count six forest, grassland, freshwater, marine, desert, and tundra , others eight separating two types of forests and adding tropical savannah , and still others are more specific and count as many as 11 biomes.
Use these resources to teach middle school students about biomes around the world. A biotic factor is a living organism that shapes its environment. In a freshwater ecosystem, examples might include aquatic plants, fish, amphibians, and algae. Biotic and abiotic factors work together to create a unique ecosystem. Learn more about biotic factors with this curated resource collection. A habitat is an environment where an organism lives throughout the year or for shorter periods of time to find a mate.
The habitat contains all an animal needs to survive such as food and shelter. A microhabitat is a small area which differs somehow from the surrounding habitat.
Its unique conditions may be home to unique species that may not be found in the larger region. Unfortunately, some habitats are threatened by pollution, extreme weather, or deforestation.
This puts many of the species that live there in danger and is causing many populations to decline. Explore different types of habitats and microhabitats with this curated collection of classroom resources. The species population size is limited by environmental factors like adequate food, shelter, water, and mates. If these needs are not met, the population will decrease until the resource rebounds.
Explore carrying capacity with these curated classroom resources. Learn about the places animals live—from the grassland to the desert and the burrow to the hive. Students brainstorm examples of familiar animals and their needs.
They learn that a habitat satisfies the basic needs that must be met for an animal to survive. Generalist species can feed on a wide variety of things and thrive in various environments. Specialist species eat a limited diet and occupy a much narrower niche. Join our community of educators and receive the latest information on National Geographic's resources for you and your students. Skip to content. Twitter Facebook Pinterest Google Classroom.
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