Answer:
Option-D
Explanation:
Plasmodesmata are the plasma membrane lined pores present in the cells of the plants. Inside these pores runs a closed tubelike structure which is an extension of the endoplasmic reticulum.
The plasmodesmata allows cell to cell communication which involves symplast mode of transport that is through its cytoplasm.
The small water soluble molecules like amino acid and sugars can easily pass through these plasmodesmata via diffusion. The large molecules can be transported through these plamodesmata through selective diffusion.
Thus, Option-D is the correct answer.
Answer:
Option A. Because of the soot covering everything, the dirtier darker moths will be eaten less often, allowing them to reproduce and pass their genes on to the next generation.
Explanation: Sooth is the black powder which is produced due to incomplete combustion of carbon containing compounds. In the england, before industrial revolution, the population of white peppered moth were high due to clean environment and unable to see by the birds during night. When industrial revolution occurs, there is sooth spread on all the trees which is black in color so the population of black peppered moth increases because they can't be seen in the dark by the birds and population of white peppered moth decreases due to easily seen by the birds.
Answer:
The correct answer will be options
1. The position of the tropomyosin threads shift
2. Exposing myosin binding sites
3. Allowing the myosin head to attach to the actin filament
Explanation:
Calcium plays an important role in the contraction of muscles especially in the formation of the cross-bridge between myosin and actin filaments.
In the presence of calcium, myosin head binds the actin filament as calcium binds to the troponin which changes the configuration of the troponin which releases the tropomyosin from the myosin-binding site on actin.
Once the myosin binding site is freed, myosin binds the site and causes muscle contraction due to ATP hydrolysis.
Thus, the selected options are the correct answer.
