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.
Plant cells have a cell wall, but animals cells do not. Cell walls provide support and give shape to plants. Plant cells have chloroplasts, but animal cells do not.
Hope this helps :)
The correct option is D.
The Taiga biome, which is also known as the coniferous forest has been described as the largest terrestrial biome because it extends across some continents of the world. The biome typically has short summers, which can be very wet and winters, which are long and can be very cold. The majority of plants in taiga biome are conifers and these plants are described as ever green because they remain green all year round.
The answer is 7.4%.
Percentage of trucks on the lot is equal to the ratio between the number of trucks and the total number of cars.
- Number of trucks ÷ Total number of cars
- 49 ÷ (49 + 612)
- 49 ÷ 661
- 7.4%
Answer:
Scientific names of animals use both the genus and species name, which is much more specific than common names, and gives more information.
For example, using the name cat just tells us that the animal is a cat
however, the scientific name felis catus, tells us that the species is catus and the genus is felis
Explanation:
