Chapter 2 : Plants Forms and Function
Plants are one of the five big groups (kingdoms) of living things.
They are autotrophic eukaryote, which means they have complex cells, and make their own food.
Usually they cannot move (not counting growth).
Plants include familiar types such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae.
The scientific study of plants is known as botany
Topics covered in this snack-sized chapter:
- Anchoring the plant to the ground
- Extracting water and minerals from the soil
There are three types of Roots:
- Taproot is large and fleshy in appearance.
- Grows deep into the ground to search food
- They are able to store food.
- Carrots and Turnips are example of taproots.
- They are close to the surface of the soil
- Collect precipitation before it sinks deep into the ground,
- Often found growing side by side with taproots: the two types of root combine efforts to maximize efficiency.
- Usually found in wheat, rice, and banana plants etc.
- Develop to help the plant to climb: for example, money plant
- Help to develop modified underground stems, such as bulbs
- Found in money plant, beans, and grape vines etc.
They support leaves and flowers physically.
Stems hold the leaves and flowers in the best position for food gathering and reproduction.
Using xylem and phloem to transport materials from areas of plenty to areas of need in various parts of the plant.
Xylem carries water through plants.
Phloem carries sugar to parts of plants
Storing nutrients for future use
The stem may be simple, branched, upright or creeping
It can form underground food storage organs.
Sun’s rays are absorbed by leaves.
The majority of photosynthetic productions (which can take place in any green part of a plant) happen on leaves.
Leaves take in carbon dioxide and release oxygen and water vapor (breathing).
Waste products of plants are extracted through leaves.
Through osmotic pressure water goes up from the roots.
Photosynthesis is the process of changing water and carbon dioxide into sugar and releasing oxygen in the presence of sunlight.
It is also called as respiration of plants because carbon dioxide is taken in and oxygen is released which is life gas for us.
Photosynthesis is necessary as living beings depends on this process. Food and respiring oxygen both products are evolved by this process.
Photosynthesis process only occurs during day in presence of sunlight, at night plants release carbon dioxide and take oxygen.
We eat almost every part of plants.
When we eat asparagus, we eat the stem of the plant.
When we eat spinach or lettuce, we are eating the plant’s leaves.
We eat the fruit of squash, cucumber and tomato plants.
When we eat corn or peas we are eating seeds.
Cauliflower and broccoli plants produce flowers we like to eat.
When we eat radish or carrot, we are eating roots.
Potatoes grow underground, but the part we eat is not a root. It is an underground stem called a tuber.
With some plants we eat more than one part.
We eat the root of the onion plant but can also eat the stems, for a milder flavor.
Some of the plants are poisonous too if we eat the wrong part. For example leaves of tomato plants are poisonous.
Plants can’t move but they find a better way to reach the sun.
You never see plants responding but according to research it is proved that plants too can sense and feel.
Travelling of plants is actually seeds of plants that moves miles away from them.
Trees have the advantage of heights to send their seeds from one place to another.
Using sunshine, air, water and a few minerals, the leaves are, in effect, the "factories" that produce food.
To gain moisture, plants typically use their roots to probe underground
Pollen is the component needed for fertilization.
Most plants rely on animals to transport the pollen from the stigma of one to other.
To do this, they attract their couriers with color and scent.
It isn't just birds that help pollination: some mammals and reptiles also do so.
However, it is mostly insects that are recruited to carry out the task.
To ensure that pollen is not wasted by being delivered to the wrong flower, some species of plant have developed exclusive relationships with their visitors.