What does plastid mean? What are protoplasts

Plastid Plastid is a general term for a class of organelles in plant cells that are enclosed by a double membrane and are present in eukaryotic plant cells. It is a semi-autonomous organelle in eukaryotic cells. The plastid is surrounded by two layers of membranes, which can increase with the elongation of the cell, and is the most important organelle in the anabolism of plant cells.

According to the different pigments and functions contained in the plastid, plastids can be divided into white bodies, colored bodies, and chloroplasts. These organelles are differentiated and developed from a common precursor: preplasts, including:

Chloroplasts, white bodies, amyloid bodies, colored bodies, protein bodies, oleosomes, etc. Some plastids have a certain autonomy and contain DNA, RNA, ribosomes, etc. This is one of the differences between animal and plant cells.

There are three differences between animal and plant cells: plant cells have cell walls, vacuoles, and chloroplasts, while animals do not. Plastids are organelles unique to green plant cells and are easily visible under a light microscope.

In juvenile cells, plastids that have not yet differentiated and matured are called preplastids. As the cell grows, the preplasts can differentiate into mature plastids. Depending on their color and function, mature plastids are divided into three categories: chloroplasts, chromosomes, and white bodies.

1 Chloroplast Chloroplast is a plastid containing chlorophyll, which is mainly found in parenchyma tissue cells in the green part of the plant body, and is the site of photosynthesis of green plants, so it is an important plastitosome. 2 Chromoplasts Chromosomes are plastids that contain pigments. Chloroplasts are also chromoplasts, but it is customary to call chromoplasts other than chloroplasts colored bodies or variegated bodies.

The colored body contains lutein and carotene and is red or orange-yellow in color. It is found in petals and fruits, and can be seen in tomato and pepper (red) pulp cells. The main function of chromosomes is to accumulate starches and lipids.

3 Leucoplast The white body does not contain visible pigments and is also called achromatic. On the white body in the cells of the storage tissue, starch or protein often accumulates, forming starch and aleurone grains that are many times larger than its original volume, which become the storage material in the cell. When the white body accumulates starch, it first starts from one place to form a core called the umbilicus, and then continues to accumulate around the nucleus, forming a concentric ring pattern around the umbilicus.

Due to the strength of the sunshine and the temperature in a day, the starch grains often appear eccentric. If you look at potato starch grains, you can see: According to the storage substances, it can be divided into:

Amyloplast (storage starch), proteoplast (storage protein), oleosomes (elaioplast, storage lipids). Some cells have white bodies that contain colorless prochlorophyll, which can be converted into chlorophyll when exposed to light, and white bodies turn green, so some people think that white bodies can also become chloroplasts.

Including chloroplasts, chromogens, white bodies.

Question 1: What are protoplasts including nucleus, cytoplasm, cell membrane, and mitochondria, etc.

Question 2: What is the difference between protoplasts and protoplasms? There is not much difference between the two. It's just a different focus.

Protoplasts: An animal cell is a protoplast; When the cell wall is removed from the plant cell, it is a protoplast; Bacterial cells, minus the cell wall, are also protoplasts. In conclusion, protoplasts, do not contain a cell wall.

Protoplasm: The living substance inside the cell, including the cell membrane, cytoplasm, and nucleus.

Protoplasts are a holistic concept; Protoplasm is a concept that emphasizes the constituent components. It can be understood this way: protoplasts, are made up of protoplasm.

To use an analogy: man and human man man: emphasis on the individual; Human: Emphasis on the whole.

Question 3: What are protoplasts? What does protoplast mean part between the cell membrane and the vacuolar membrane.

Question 4: What is a protoplast, what is its function, and what is it used A cell that has shed its cell wall is called a protoplast, which is a concept of bioengineering. Animal cells can also be counted as protoplasts.

Question 5: What is protoplasmic layer, protoplast, protoplasm, and what is the difference between the three? You can see the difference:

The protoplasmic layer exists in mature plant cells and is a semi-permeable membrane of mature plant cells, which refers to the cell membrane vacuolar membrane and the cytoplasm between the two membranes;

Protoplasts: Plant cells that have been stripped of their cell walls are called protoplasts, which are a general idea of bioengineering. Animal cells can also be counted as protoplasts.

Protoplasm: is a general term for the living matter in the cell. Its main components are proteins, nucleic acids, lipids.

Protoplasm differentiation gives rise to cell membranes, cytoplasm, and nucleus. An animal cell is a protoplasmic mass. Plant cells are made up of protoplasts and cell walls.

Question 6: What are protoplasts made of? Cell membranes are cytoplasmic organelles (organelles include: mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, etc.).

Physics concepts.

Definition: A center of mass can be used.

centroid) to represent an abstract body of matter.

Explanation: A mass body has only one centroid. A mass can be an object or a combination of complex silver-numbered objects.

For example, the Earth is a mass, and if the Earth and the Moon are combined, they are also a mass, because they have only one common centroid. A mass can be a virtual mass particle, such as atoms and electrons. Mass bodies not only have a fixed form, but also can have no fixed form, such as gases, etc.

As long as it is a material body that can be represented by a centroid, regardless of size, structure, or form, it is a mass body.

Plastids: Plastids are structures unique to plant cells;

Plastids include: 1. White body: does not contain acorns, and is distributed in the part of the plant body that does not see light. It has the function of storing starch and oil droplets;

2. Chromosomes: containing lutein and carrot and carrot, which are distributed in the cells of fruits and petals, so that fruits and petals show color;

3. Chloroplasts: containing chlorophyll and carotenoids, mainly found in the mesophyll cells of withered plants and the cortex cells of young stems, and are the places for photosynthesis and synthesis of organic matter.

Liposomes are an artificial membrane. In the water, the hydrophilic head of the phospholipid molecule is inserted into the water, and the hydrophobic tail of the liposome extends to the air, and after agitation, it forms a spherical liposome with a diameter of 25 to 1000 nm.

Liposomes can be used for transgenesis, or to prepare drugs, using the characteristics of liposomes that can fuse with cell membranes to send drugs into the cell Biological definition: When amphoteric molecules such as phospholipids and sphingolipids are dispersed in the aqueous phase, the hydrophobic tails of the molecules tend to clump together and avoid the aqueous phase, while the hydrophilic head is exposed to the aqueous phase to form a closed vesicle with a bilayer structure, called liposomes. Accompaniment.

Protoplast: Cells that have lost their cell walls are called protoplasts, which is a concept of bioengineering.

Protoplast fusion.

Gram-positive bacteria treated with lysozyme or penicillin (pectinase and cellulase can also be used) can completely remove the cell wall and form a cell body that encloses the cytoplasm only by the cell membrane. After treating plant cells with pectinase and cellulase, the cell wall can be completely removed, and the cytoplasm is encapsulated only by the cell membrane. Animal cells are equivalent to protoplasts (but are somewhat different from protoplasts).

Protoplasts are formed by the differentiation of protoplasm, including cell membranes and intramembrane cytoplasm and other organelles with vital activity. Plants and animals such as nucleus, mitochondria, and Golgi apparatus, etc., while bacteria such as ribosomes, nucleoids, etc.

Protoplasts are the smallest units of a viable plant cell that are left of the cell wall after the cell wall has been removed. The separation of protoplasts was studied earlier, and in 1892, Klercker first used mechanical methods to isolate protoplasts.

In 1960, British plant physiologist Coeking was the first to use enzymatic hydrolysis to isolate protoplasts from the roots of tomato seedlings and achieved success. It was not until cellulase and segregation enzymes were put into the market that plant protoplast research became a hot field. So far, protoplasts can be isolated from almost every part of the plant body, and complete plants can be regenerated from the protoplasts of 70 plant species, including tobacco, carrots, petunias, eggplants, and tomatoes.

In addition, protoplast fusion and somatic cell hybridization technology have also been widely used. Although protoplasts do not have a cell wall, they still have the nature of living cells and can carry out various basic life activities. A large number of experiments have shown that protoplasts without cell walls are still "totipotent" and can be regenerated by ex vivo culture.

It is easier than intact cells to ingest foreign genetic material, organelles, bacteria, viruses and other microorganisms, and under certain conditions, they can be induced to fuse to form hybrid cells, so protoplast research has opened up a new way for genetic transformation and plant breeding practices in higher plants.