in this video, we're going to begin our lesson on plant viruses. And so plant viruses are actually very similar to animal viruses, including their morphology or their shapes as well as their nucleic acid types. Now, most plant viruses are going to be non enveloped RNA viruses that can enter the cell during an infection. And so down below we're showing you a section that's focusing on the differences between animal viruses and plant viruses. And so really there are three major differences between animal and plant viruses. And so we have those three differences number down below and those numbers that you see here correspond with the numbers that you see in our image. And so the first major difference between animal and plant viruses is that unlike animal viruses, plant viruses do not rely on interactions with host cell receptors for attachment and entry. Instead, the entry of plant virus is going to occur in a host cell via wound sites on the plant. And so these wound sites can be caused by physical damage to the plant that damages the cell walls of the plants. And that is how the viruses can enter. Now this physical damage to the plant can be caused by many different things, including insects that might be crawling on the plants. So if we take a look at our image down below, notice that we're showing you the unique characteristics of plant cell viruses. And the first one that we're listening here is that entry of plant cell viruses occurs uh into the host via wound sites on the plan. So you can see here, we're showing you the wound sites as these black uh circles here. Now the second major difference between animal viruses and plant viruses is going to be the transmission between multiple organisms. And so unlike animals, um plants can not move around so animals can move around and they can transmit the virus simply by just moving around and coming into contact with other animals. Plants they sit where they are. And so plant viruses rely on transmitters for the virus to go from one organism to another. And so plant virus transmitters include insects, which can go from one plant to another plant and transmit the virus, soil contaminated seeds and even the growers. Humans can be transmitters of plant viruses transmitting the plant virus from one plant to another plan. And so down below, we're just showing you some examples of transmitters of plant viruses, insects, humans, worms, and soil can all be examples of transmitters. And so the third major difference between animal viruses and plant viruses is that the infection of adjacent plant cells occurs via the plasma. So, Dez Mata, which recall are these openings in the cell walls between adjacent cells, adjacent plant cells. And so notice down below over here we're showing you how the plasma does Mata is really how adjacent cells can be infected by the plant virus. And so notice down below in this image, we're showing you two neighboring plant cells. We have one plant cell right here and we have another plant cell over here and these two neighboring plant cells. Their cytoplasm are connected via these plasma Dez Mata. These openings in the cell wall here and these openings in the salt wall can allow for plant viruses to make their way to infect neighboring cells in that fashion. And so this year concludes our brief lesson on plant viruses and we'll be able to get some practice applying these concepts as we move forward in our course. So I'll see you all in our next video.

in this video, we're going to talk about the plant virus infection cycle. And so the infection cycle of a plant virus, which can be transmitted via an insect actually occurs in a series of four steps that we have numbered down below in our image, one through four. And so what you can see here is that in the very first step of a plant virus infection, the very in or the plant viral particle is going to enter the plant cell at a wound site. And so what you'll notice here is that the plant up here is wounded and you can see that it's cell wall has been damaged perhaps by an insect. And so this allows for the very in again the plant viral particle to enter into the plant cell. Now, in the second step of a plant virus infection, the genome is going to be replicated, the viral genome will be replicated and viral captured proteins are going to be synthesized specifically in the nucleus. And so you can see here that within the nucleus that all of these viral captured proteins and viral genomes are being synthesized and replicated. Then, in the third step of a plant virus infection, the mature variant or the mature plant viral particles are going to be assembled in the cytoplasm of the plant cell. And so you can see that in the third step here, the assembly of the plant viral proteins and the plant viral genomes is going to occur in the cytoplasm. And so these new viral particles are going to be produced. And then in the 4th and final step of a plant virus infection, the variance can basically enter into adjacent cells via the plasma DEZ model, which are the openings that you see here between plant cells. And so you can see that the variant is able to move to a neighboring plant cell over here via these plasma dez mata, these openings in the cell walls of leaves. And so this allows for the virus to continue its infection and neighboring plant cells. Now, it is important to note that the plant viral infection of plants usually stunts their growth and so the growth of the plant is going to be uh inhibited uh and limited, but it may also kill the plant as well. And so uh this year concludes our brief lesson on plant virus infection cycle and we'll be able to get some practice applying these concepts as we move forward. So I'll see you all in our next video.