A seed (also called a kernel) is a small embryonic plant enclosed in a protective covering called the seed coat. It is the product of a ripened ovule in angiosperm and gymnosperm plants.
Seeds store food and help the new plant grow. They are a major source of food for animals and people, and are also used in plant breeding to produce new varieties of plants with desirable characteristics.
What is a seed?
A seed is a part of a plant that can grow into a new plant. It has three basic parts: an embryo, a supply of nutrients for the embryo and some sort of protective cover to protect the seed from damage.
The seeds of flowering plants, called angiosperms, are encapsulated by a seed coat (testa) that provides protection from water and temperature changes, and food reserves for the growing embryo. Cotyledons (embryo leaves) are present within the seed and help to classify angiosperms into dicots and monocots.
Many common seeds, such as peas, beans, peanuts and sesame, are edible. Seeds are also used to make many commercial products, including cotton and flax fiber, which is used in textile production. Some nonfood oils are extracted from seeds, such as linseed oil.
How do seeds grow?
Seeds are the basic unit of reproduction for most flowering plants. They contain an embryo (a miniature undeveloped plant) and food reserves enclosed within a protective coat or coats.
To grow, seeds need the right conditions such as water, oxygen and temperature. They also need a time when these conditions are favorable for germination, which is the process by which seeds transform into seedlings.
Many seeds remain dormant until they encounter a specific set of germination triggers that tell them it is time to break out of their dormancy. These triggers vary from species to species, and depend on moisture, temperature, oxygen and light.
To make this determination, seeds use tiny brains that act like the ones found in our own bodies. These brains, based on bundles of specialized cells, process hormone signals that tell them when it is prime time to break dormancy and start growing.
How do seeds store food?
Seeds are an important source of food for many people around the world. They include grains, legumes and nuts and are an integral part of a healthy diet.
Depending on how and where they are stored, seeds can be kept for years. However, their longevity depends on a variety of factors including temperature, moisture and light exposure.
The most common way to store seeds is in a cool, dry place where they will stay crisp and fresh for years. These conditions help preserve the quality of the seeds and encourage germination.
How do seeds germinate?
Seeds have to undergo a process called germination in order to grow into plants. This process begins when seeds are placed in the soil and watered properly.
Water is a vital component to seed germination because it provides the seeds with water and oxygen they need to survive. However, too much water can cause the seeds to drown, so it’s important to follow the instructions on the seed package for how deep to plant them and how much water they need.
Temperature is also an essential element to seed germination, since it affects the seeds’ metabolism and growth rate. A moderate temperature of 25 to 30degC is the ideal range, but some seeds require special conditions either lower or higher than this.
How do seeds grow into plants?
The transformation from a seed to a plant isn’t as simple as “just add water”. For many plants it takes weeks – even months – before they sprout.
During this time, seeds need energy (from light) and moisture. They also need nutrients from the soil they are planted in.
Every cell in a plant has a list of instructions called DNA, which describes how that cell should look, work, and grow.
These instructions tell the cell where to get its food and where to find oxygen.
During this time, the embryo inside the seed coat is dormant until conditions are right for germination. Some species require specific light and temperature conditions, while others only need the presence of oxygen and a little water to spring into action.