* More than 40 proteins and glycoproteins involved in the complement system are synthesized by the liver, macrophages, epithelial cells, they are present in the blood in plasmatic form, membrane, some have an enzymatic activity, regulator or membrane receptorThese are elements of the humoral innate immune response, they fight infections, purify immune complexes and apoptotic bodies.
<span>There are indeed three ways to activate the complement:</span>
Classical pathway: Activated by Immunoglobulins in immune complexes, aggregated Immunoglobulins, DNA, CRP, apoptotic bodies .......it involves nine fractions, starting with C1, then C4, C2, C3, to form a classical C5 convertase, then, activation of C5, C6, C7, C8, C9.
Alternative pathway: activated by polysaccharides (bacterial endotoxin), vascular wall poor in sialic acid, aggregated IgE ...C3b like is the first component in the alternate channel cascade, it will create an amplification loop, and form an alternative C5 convertase.
Lecithin pathway: Activated by mannose, fucose (carbohydrate of microorganisms)The first component is the complex MBL / MASP1 / MASP2: "mannose-binding protein": works according to the same principle as the complex C1 of the classical way (MASP2 cleaves the C4 and the rest of the cascade is equivalent to that of the classical way).
the three ways have the same outcome: A C5 convertase (formed by one of the pathways) cleaves C5 into C5a and C5b: C5b is deposited far from other fractions on the antigenic surface. The fixation of C5b in the cell is followed by that of C6, C7, C8, and C9 (9 molecules of C9): formation of the membrane attack complex (MAC) ==> Death of the cell by osmotic shock
<h2>Angiosperms </h2>
Explanation:
Angiosperms are the most diverse group of plants, some statements which reflect angiosperm adaptations to life on land:
- Flowers attract animal pollinators carrying pollen from other plants of the same species
- Fruits aid in the dispersal of seeds by wind or by animals that carry or eat the fruits
- In many angiosperms, the male gametophyte contained in a pollen grain can be transported many miles away by wind or animal pollinators
- Floral parts of the sporophyte protect the reduced female gametophyte from drying out and from UV radiation
- Seeds protect and nourish plant embryos, and fruits protect the seeds
- Seeds enable plant embryos to be dispersed long distances from the parent plant via wind or animals
Answer: The correct answer for the fill in the blank is B) Advantageous traits become more common in a population.
Theory of natural selection was given by Darwin. This is one of the mechanisms of evolution.
According to this theory, organisms that are better adapted to their environmental conditions survive and increase their population by reproduction. So they pass the advantageous trait to the next generation. In other words, it reflects the survival of the fittest.
Due to this, the advantageous trait becomes more common in the population.
Thus, the correct option is B)
"Gravitational attraction" is initially responsible for the formation of the clumps of matter within this interstellar cloud.
<u>Answer:</u> Option C
<u>Explanation:</u>
About 4.6 billion years ago, the solar systems were a bunch of gases and dusts, referred to solar nebula. Gravity squeezed the material as it started to rotate, creating the sun at the middle of the fog.
The rest of the material began to accumulate with the sunrise. The smaller particles moved together to form larger particles that were connected by gravity. As lumps develop, gravity increases and turns into kinetic energy of moving particles that collide and produce heat.