Answer:
c) thin filaments slide past thick filaments towards the M line
Explanation:
Each muscle fiber has many myofibrils composed of many sarcomeres which have thick and thin filaments. Thick filaments are made of myosin protein whereas thin filaments have actin protein. There are various bands and zones in a sarcomere like A band, I band etc. H zone consists of only thick filaments. It has a central vertical line called as M line where the accessory proteins hold together the thick filaments.
According to sliding filament mechanism, sarcomere must shorten for muscle to contract. However sarcomere shortening is not caused due to shortening of thick and thin filaments. Instead they slide over each other towards the M line which leads to shortening of sarcomere without changing the length of filaments. The sliding is caused by forming of cross bridges between actin and myosin proteins.
Answer:
limpet
Explanation:
This has a single, "limpet-like" shell on top, which is made of proteins and chitin reinforced with calcium carbonate, and is secreted by a mantle covering the whole upper surface. The underside of the animal consists of a single muscular "foot". Although molluscs are coelomates, the coelom tends to be small.
Answer:
Option (2), (3) and (4).
Explanation:
Charophytes are the group of some green algae of fresh water. The cahrophyta can be included in both the division and super division. Embryophyta has been emerged from the charophyta.
A student confirm whether the algae is charophyte or not by looking at the specific features. The cahrophytes has well defined sexual characters and the structure of sperm cell, the presence of phragmoplast confirms the charophytes. The cellulose synthesizing ring complex is also present in charophytes.
Thus, the correct answer is option (2), (3) and (4).
If referring to photosynthesis, carbon dioxide is brought into the cholorplast of the plant cell, it is then fixed to RUBP, it will go through a series of Redox reactions and become G3P. RUBP is then recycled and is used to fix more carbon dioxide. You need two G3P molecules to become glucose.
Answer:
Dinosaurs are the extinct organisms that belong to the class reptilia. Dinosaurs are the most advanced and bulkier reptiles at the history time and they were overspecialized in their environment.
The dinosaurs extinct rapidly due to the change in the external conditions and the volcanic eruptions that occur at the dinosaurs time. The recent searcher claims that asteroid impact and massive volcanic eruption leads to the dinosaur extinction. The fossil evidence and the presence of the specific basalt and other chemicals are found in the volcanoes and in the asteroid.
