The following adaptations allow plants to survive in the hot desert environment: Small leaves - these ensure that less water is lost from the plant by transpiration because the leaf has a smaller surface area.
Tap roots - these are long roots metres long that reach deep under the ground to access water supplies. The tap roots are much longer and bigger than the plant which is visible at the surface. Spines - some plants have spines instead of leaves eg cacti.
Each time a plant opens its pores, some water escapes. This is called transpiration. Replacing this lost water is not easy with so little annual moisture, and if the water cannot be replaced, the desert plants will die. So desert plants have acquired special adaptations that help them reduce water loss. Here are some of their adaptations:. One way desert plants, trees, and shrubs suck up as much water as possible is by growing very deep taproots. Sometimes these roots can get to be more than feet long.
The above-ground parts of a plant may remain small for years simply because the plant puts most of its energy into developing its taproot system. Desert plants may have a huge, tangled network of shallow roots that spread out from the plant in all directions. The roots can be as long as the plant is tall, allowing the plant to quickly absorb water from the slightest rainfall.
Desert plants can soak up water, store it, and prepare to use it during drought. For example, cacti and many other desert plants store water in their fleshy leaves and stems. Desert plants may also have other adaptations for water storage, such as pleats or folds that will allow the plant to swell with added water when it can.
The pleats or folds can almost disappear if the plant soaks up a lot of water; then the plant can shrink, and its pleats or folds can become visible again as drought sets in and the plant makes use of water it has stored.
Though many desert plants die to the ground during the hottest part of each year, the water they have stored in underground roots, tubers and bulbs will sustain them until the next moist period. Why do plants grow hairs and spines? The hairs and spines that grow on desert plants help reduce moisture loss by breaking the effects of the wind.
They also help to cast small shadows on other desert plants, which can protect them from the sun. The hairs and spines can even serve to reflect the sun's rays away from plants because of their shininess. Lastly, hairs and spines can help protect plants from hungry animal predators. Scientists believe that desert plants may produce and give off chemicals from their leaves or roots that keep other plants from growing nearby.
It is thought that plants do this to reduce competition, especially when water is scarce. Some desert plants cope with the desert's dryness by not coping at all. As a result, during drought they are present only as seeds in the soil. When the right amount of rain falls and soaks into the soil, they sprout and bloom. When this happens the desert's dry brown landscape can quickly change into colorful fields of wildflowers, herbs, and grasses.
Most of these fast-growing desert plants do not last very long. So aside from having seeds that are adapted to drought, they have few or no special adaptations to desert conditions. This is why desert plants of this kind sprout, flower, and leave behind a generation of seeds as quickly as possible. Short-lived desert plants like this are called ephemerals.
With little water available to help them grow, dormant ephemerals are covered and protected by natural chemicals called inhibitors. The primary function of inhibitors is to keep seeds from germinating until enough moisture and specific temperatures are present.
Once the inhibitor has been washed off, the seeds can sprout. Hence, layer of cutin is present on epidermis, which is a thick waxy coating. This waxy coating helps in minimising water loss by transpiration. Epidermis, in botany, outermost, protoderm-derived layer of cells covering the stem, root, leaf, flower, fruit, and seed parts of a plant.
The epidermis and its waxy cuticle provide a protective barrier against mechanical injury, water loss, and infection. The epidermis, the outermost layer of skin, provides a waterproof barrier and creates our skin tone. The dermis, beneath the epidermis, contains tough connective tissue, hair follicles, and sweat glands. Cells of epidermis form a continuous layer without intercellular spaces. It protects all the parts of the plant. It performs the function of absorption in the roots.
It may have a waxy covering called cutin which prevents loss of water in desert plants. So plants inside a greenhouse can grow faster than plants outside because they are being cared for by humans in ways that we know makes them grow fast. Some plants can thrive both indoors and outdoors, providing that they are brought in during the coldest months.
Since many indoor plants are tropical, they grow well in the more humid outdoors, and breezes help fight off houseplant pests and fungal diseases. Skip to content Natural sciences.
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