Plants, animals, microorganisms, how to choose

Animals, plants and microorganisms, first of all, the cell structure is different, plant cells have cell walls, vacuoles, chloroplasts, while animal cells do not, microorganisms are generally unicellular organisms that do not have or have an unformed nucleus, and some also have, while the first two have. Secondly, animals and microorganisms are active, plants are not.

1.The definition of an animal is: a multicellular organism with eukaryotic cells, cells without a cell wall, and the vast majority of animals can move freely.

2.The definition of a plant is: a multicellular organism with eukaryotic cells, cells with a cell wall, and the vast majority of plants cannot move freely.

3.The definition of microorganisms is: a general term for all living beings except animals and plants, the modern definition:

Microorganisms are all tiny organisms that are invisible or invisible to the naked eye, including bacteria, viruses, fungi, some small protozoa, microscopic algae, etc.

The difference between animals, plants and microorganisms is the difference in size.

The difference between animals and plants is whether they are autotrophic or not.

Biologists conduct scientific research on selected biological species to reveal a certain life phenomenon with universal laws, and in this case, the selected biological species is a model organism. For example, Mendel used peas as experimental materials to reveal the genetic laws of the biological world, while Morgan used fruit flies as experimental materials, and in their research, peas and fruit flies are model organisms for studying the genetic laws of organisms.

Animals include: Caenorhabditis elegans, fruit flies, Xenopus laevis toad, salamanders, mice, sea urchins, zebrafish and other plants: Arabidopsis, rice, etc.

Microorganisms are: bacteriophage, Escherichia coli, Saccharomyces cerevisiae.

With the development of life science research, new species will be used as model organisms. But they will have some basic things in common:

2) harmless to humans and the environment, easily accessible and easy to raise and breed in the laboratory;

3) Short generations, many offspring, and clear genetic background;

4) Easy to perform experimental operations, especially with genetic manipulation methods and phenotypic methods. Reference.

Bolinco refers to the survival or growth of animal and plant cells under in vitro conditions. Animal and plant cell culture is very different from microbial cell culture (Table 14-1).Because animal cells have no cell wall, most mammalian cells can only grow if they are attached to solid or semi-solid surfaces; Strict nutritional requirements, in addition to amino acids, vitamins, salts, glucose or galactose, serum is also required.

Animal cells are sensitive to the environment, including pH, dissolved oxygen, C02, temperature, and shear stress, which have stricter requirements than microorganisms, and generally need to be strictly monitored and controlled. In contrast, plant cells have simpler nutrient requirements than animal cells. However, plant cell culture generally requires a certain concentration of culture products to be obtained at high density, and the growth of plant cells is slower than that of microorganisms, so long-term culture has special requirements for aseptic conditions and reactor design.

In biotechnology, people have used a large number of cultures of bacteria and filamentous fungi to produce various enzymes, antibiotics, proteins, amino acids and other products, but many valuable biological substances, such as toxins, vaccines, interferons, monoclonal antibodies, pigments, flavor substances, etc., must be obtained with the help of large-scale culture of animal and plant cells. Since the 50s of the twentieth century, some progress has been made in this area. However, the current technology is far from meeting the requirements of the application of cell biological products, and with the deepening of the research on animal and plant culture technology, it shows broad development prospects.

Table 14-1 Culture characteristics of animal, plant and microbial cells Species Comparison items Microorganisms Animal cells Plant cells Large Small Suspension growth Nutritional requirements Growth rate Metabolic regulation Environmental sensitivity Cell differentiation Shear stress sensitive Traditional variation, screening technology Cell or product concentration 1 10m Can Simple Fast, doubling time is small Internal Insensitive None Low Widely used High 10 100m Most cells need to attach to the surface in order to grow Very complex Slow, doubling time 15 100 hours Internal, hormones Very sensitive Yes Very high Not often used Low 10 100m OK, but easy to clump, no single cells More complex Slow, doubling time 24 74 hours Internal, hormones Can tolerate a wide range There are high Sometimes use low.

1. Compulsory.

Introduction 1 Organisms share a common material and structural basis.

2 Structurally, in addition to the virus.

There are many differences. Microorganisms refer to fungi, bacteria, viruses, ruan viruses and other organisms with simple structures, most of which are saprophytic or parasitic; Animals and plants are multicellular organisms, most of which have complex structures, and can be divided into two categories: autotrophic and heterotrophic according to the energy pathway. There are several modes of microbial reproduction, such as fission and proliferation, which are asexual reproduction; The lower animals and plants are asexual and do not undergo pollination, while the higher animals and plants are mostly sexually reproductive, and the animals are viviparous and oviparous.

The similarity is that they are all living beings, they all need to obtain energy from the outside world, and they all have life activities.

If you subdivide it again, you can summarize the characteristics of each category, but I don't know what the answer you want is.

1. Animals and plants are active in nature to find prey, while plants are fixed in one place to absorb nutrients, microorganisms are small, and only have basic reproductive and survival functions. The similarity is that all three have metabolic functions.

Similarities: all living things, differences: animals - consumers Plants - producers Microorganisms - decomposers.

(1) Eucalyptus saplings, small eucalyptus and large eucalyptus trees in a forest belong to the same species of eucalyptus, and all their individuals constitute a population; Different populations such as animals, plants, and microorganisms in a certain area constitute a biological community

2): Blood belongs to connective tissue and belongs to the tissue level;

Teeth belong to the organ level;

Neurons are nerve cells and belong to the cellular level;

A group of crucian carp in the pond belongs to the population level;

All living things on Earth belong to the community level;

A tree belongs to the individual level;

The heart, blood vessels, and blood belong to the circulatory system;

A city is an ecosystem

Therefore, the answer is: (1) population; Community

2) Connective tissues, organs, cells, populations, communities, individuals, circulatory systems, ecosystems.