INTRODUCTION
The stem of a plant is a long structural component that contains leaves and flowers. A plant’s stem provides support and facilitates in the transportation of resources to all parts of the plant. It also preserves and promotes a plant’s development and growth. Stems might be a few millimetres long or hundreds of metres long. Depending on the plant, they can also vary in diameter. Although the stems of some plants, such as the potato, develop underground, normally they are above the ground. Herbaceous or woody stems are seen in nature. Stems provide support to the plant, leaves, flowers, and buds; in rare cases, it also serves as food storage for the plant. A stem can be either unbranched, as in a palm tree, or densely branched, as in a magnolia tree. The plant’s stem connects the roots to the leaves, allowing absorbed water and nutrients to be transported to different sections of the plant. The stem also helps in the movement of photosynthetic products (such as sugars) from the leaves to the rest of the plant. The existence of nodes and internodes distinguishes plant stems, whether above or below ground.
FUNCTIONS OF STEM
The plant stem connects the roots to the leaves, provides support, stores food, and holds the leaves, flowers, and buds during the growth and development of the plant.
Branches, leaves, flowers, and fruits are all supported by the stem.
Branches and leaves are spread out by the stem so that they may obtain enough sunlight.
Water and mineral salts are transported through the stem to the branches, leaves, flowers, and fruits.
Green stems create a small amount of food through photosynthesis when they are young.
The stem of a plant acts as a support structure for its above-ground components as well as a channel for water and nutrients.
The stem’s primary duties are to support plant leaves, transfer nutrients and water from the soil, and transport sugar or glucose. The stem transports photosynthetic products and nutrients to the roots and leaves, along with water.
Other significant and common functions include: –
It is responsible for supporting and maintaining leaves, flowers, and fruits, as well as transporting water and nutrients from the roots to the rest of the plant. It includes the transportation system that allows water and sap to travel horizontal and vertical within the plant body.
The stem enables the leaves to form in such a way that they can receive direct sunlight and perform photosynthesis effectively. Gas exchange is also possible due to the arrangement and positioning of the leaves. Photosynthesis is carried on by the green stems.
The vascular bundles of stems include xylem and phloem, which transport water and nutrients all through the plant.
Pollination, fertilisation, and seed dispersion are all made simpler by stems producing flowers and fruits. It links the roots and supports the leaves, flowers, and fruits.
Some stems are damaged in order to store food and water. The main stem or trunk of trees and shrubs provides a strong columnar structure to which branches are connected, allowing the leaves to be exposed to the sun more completely.
Chloroplasts are found in a small number of green stems, and they are responsible for photosynthesis.
STEM CELLS DEFINITION
Stem cells are the body’s raw materials — they are the cells that give rise to all other cells with specific tasks. Stem cells divide to produce new cells called daughter cells under the correct conditions in the body or in the lab.
These daughter cells differentiate into new stem cells or specialised cells with a specific purpose, such as blood cells, brain cells, heart muscle cells, or bone cells (differentiation). No other cell in the body has the potential to create new cell types on its own.
USES OF STEM CELLS
Regeneration of tissues
The most common use of stem cells is tissue regeneration.
Previously, someone in need of a new kidney had to wait for a donor and then undergo a transplant.
There is a lack of donor organs, but scientists might use stem cells to generate a certain tissue type or organ by instructing them to develop in a specific way.
For example, scientists have previously created new skin tissue using stem cells from just under the skin’s surface. They can then transplant this tissue onto damaged skin to treat a severe burn or other wound, and new skin will grow back.
Therapy for cell deficiency
Scientists hope to be able to create healthy heart cells in the lab and transplant them into patients with heart disease one day.
By repopulating the heart with healthy tissue, these new cells may be able to repair cardiac damage.
People with type I diabetes, meanwhile, may get pancreatic cells to replace insulin-producing cells that their immune systems have lost or destroyed.
The only current treatment option is a pancreatic transplant, however only a few pancreases are available.
Treatments for blood diseases
Adult hematopoietic stem cells are now commonly used to treat disorders including leukaemia, sickle cell anaemia, and other immunodeficiency issues.
Haematopoietic stem cells are found in the blood and bone marrow and can generate all blood cell types, including oxygen-carrying red blood cells and disease-fighting white blood cells.
CONCLUSION
The stem is the plant’s support system that bears leaves, buds, flowers, and fruits and grows from the embryo’s plumule and epicotyl. It transports water and nutrients received by the roots to the rest of the plant’s components.
The three types of aerial stems are aerial stems, subaerial stems, and subterranean stems. These stems have been modified to aid the plant in a variety of other vital activities, such as food storage, photosynthesis, climbing, reproduction, and so on.