Solar sails are used to increase speed.
Answer:
Most ocean pollution begins on land.
Much of this runoff flows to the sea, carrying with it agricultural fertilizers and pesticides. Eighty percent of pollution to the marine environment comes from the land. One of the biggest sources is called nonpoint source pollution, which occurs as a result of runoff.
This statement is true.
As the sickle cell allele was a mutation in the cell, but it helped prevented Malaria in the countries close to the equator. As this mutation helped many resist against Malaria and nature did not let this mutation die out because it still helps many people.
Answer:
(a) Microfilaments
(b) Microtubules
(c) Microtubules
(d) Microfilaments
(e) Intermediate filaments
(f) Microfilaments, intermediate filaments, microtubules
(g) Microfilaments, microtubules
(h) Microfilaments, intermediate filaments, microtubules
(i) Microtubules, microfilaments
(j) Microtubules
Explanation:
Microtubules (MTs) are dimers of the protein tubulin (alpha- and beta-tubulin subunits) and they are major components of the cytoskeleton. MTs play diverse cellular roles including, mechanical support (cytoskeleton), transport, motility, chromosome segregation, etc. Microfilaments (MFs) are protein filaments that also form part of the cytoskeleton in eukaryotic cells. MFs consist of G-actin monomers assembled in linear actin polymers, and their functions include mechanical support, cytokinesis, changes in cell shape, amoeboid movement, endocytosis and exocytosis, etc. MFs associate with the protein myosin to generate muscle contractions. Actin filaments/MTs assembly from monomeric actin/tubulin is caused due to energy expenditure, where ATP/GTP bound to actin/tubulin is hydrolyzed during polymerization. Finally, intermediate filaments (IFs) are a type of cytoskeletal element composed of a heterogeneous group of structural elements, and they are not found in all eukaryotes. The primary function of the IFs is to contribute to the mechanical support for the plasma membrane where these filaments come into contact with other cells and/or with the extracellular matrix. The IFs are not directly involved in cell movement. All 3 types of cytoskeletal elements (microfilaments, intermediate filaments, microtubules) can be visualized by fluorescence microscopy when cells express chimeric MT/IF/MF.–GFP fusion proteins.
