Human activity can affect the river ecosystems because first of all humans take the water and use it for themselves, they also pollute it, disturb the ecosystems and kill fish or oysters etc. in the ecosystems.
Answer:
"As a molecule moves through the plasma membrane it passes through <em>a hydrophilic layer of phospholipid heads then a hydrophobic layer of phospholipid tails and then another hydrophilic layer of phospholipid heads".</em>
Explanation:
Biological membranes are formed by two lipidic layers, proteins, and glucans.
Lipids characterize for being amphipathic molecules, which means that they have both a hydrophilic portion and a hydrophobic portion at the same time. These molecules have a lipidic head that corresponds to a negatively charged phosphate group, which is the polar and hydrophilic portion. They also have two lipidic tails that correspond to the hydrocarbon chains -the apolar and hydrophobic portion- of the fatty acids that esterify glycerol.
Membrane lipids are arranged with their hydrophilic polar heads facing the exterior and the interior of the cells, while their hydrophobic tails are against each other, constituting the internal part of the membrane.
Through this lipidic bilayer, some molecules can move from one side of the cell to the other, which happens because of concentration differences. When this occurs, molecules must pass through the hydrophilic layer of phospholipid heads then through the hydrophobic layer of phospholipid tails and then again through another hydrophilic layer of phospholipid heads.
Answer:
Some practices from the recommended list of physical/cultural control that you could do year-round to help control pests are as follow:
1. We can use those plant species that are more competitive. These plant species include release of chemical toxins that suppress other plants and insects.
2. Use of large Hight quality seeds.
3. By using narrow spacing in row and increasing seeding rate.
4. By using shallow seeding technique which allow desired plant species to grow and develop faster above the surface of soil.
5. By ensuring that our plant species is perfectly placed in that growing environment which is optimized with every specs.
6. By rotating the crops
7. By rotating plant species with different growing cycles and seasonal cycles.
8. By rotating herbicides with alternative modes of action to delay the herbicide resistance development.
Spherical shaped bacteria are known as coccus bacteria.
It’s the first choice because the C at the end does not pair with anything, it was an extra pair that was made