Answer:
<u>d. Transport proteins within the membrane serve as a tunnel for molecules to enter the cell.
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Explanation:
Solutes are typically moved across the cell through either passive or active transport. The cells, surrounded by a bilipid layer or plasma membrane is amphiphlic- its polar, hydrophilic lipid heads face outwards, while their non-polar hydrophobic lipid tails face inwards towards each other.
While lipid-soluble molecules move across the layer easily, it is also difficult for charged and also large molecules to move across its surface, into the cell. Transmembrane channels, <u>embedded within the membrane</u>, help to maintain selective permeability as transport proteins, pores and gated channels. Simple diffusion happens as a method of passive transport in cells through plasma membranes.
The solutes travel through the plasma membrane in the process of diffusion from regions of high concentration to regions of low concentration; this occurs without the use of energy. <u>Molecules moving against their concentration require active transport mechanism to cross the membrane</u>.
Answer:
because the male Scorpio is tutorial
Answer:
The immune system is closely associated with the lymphatic system
Explanation:
The endocrine system is a organ system that produce and secrete hormones all over the body. All the organ systems are interconnected and depend on each other and can be composed of different types of cells and tissues. But is it true that the immune system is closely associated with the lymphatic system because the lymphatic system rid the body out of toxins.
Answer:
ovule
The fertilized ovule becomes the seed, and the ovary becomes the fruit. Petals are also important parts of the flower, because they help attract pollinators such as bees, butterflies and bats. You can also see tiny green leaf-like parts called sepals at the base of the flower.
Explanation:
The question is incomplete as it does not have the options which are:
A. The threefold change happened in one concentrated burst.
B. The change was not consistent in direction, but happened in multiple bursts concentrated at each speciation event.
C. There was consistent directional selection toward a larger brain all along the lineage between the two species.
D. None of the above.
Answer:
Option-B
Explanation:
The hominids evolved with time and the known hominid in modern time is the Homo sapiens or modern human.
The Homo sapiens like other species could have evolved from the older species through speciation and studies suggest that one of the major factors of human evolution is the size of the brain.
Two possibilities could explain the size of the brain that it could have evolved slowly with time called the gradual equilibrium or in bursts concentrated at each speciation event.
Since the punctuated equilibrium takes place in bursts until the species reach stasis is the most applicable condition for punctuated equilibrium to happen therefore Option-B is the correct answer.
