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:
The correct answer is - e. many different molecules form a signaling cascade.
Explanation:
Signal transduction is the number of events that take place inside the body of a human from the external atmosphere to transmitting a chemical or physical signal through a number of molecular events of signaling cascade.
The transmission of the particular chemical or physical signal is caused a sequence of phosphorylation events inside the cell it involves specific protein receptors and different types of molecules.
2 because animals do not have chloroplast or a cell wall
Scientific Theory change but not thrown away because scientist
continue looking for possibilities and exact proportion to prove such theory,
though it is change because they always conducted hypnosis in every theory and
once it proves something different they conduct another hypothesis for more
actual evidence.
Answer:
deoxyribose
Explanation:
A phosphate backbone is the portion of the DNA double helix that provides structural support to the molecule. DNA consists of two strands that wind around each other like a twisted ladder. Each strand has a backbone made of alternating sugar (deoxyribose) and phosphate groups.
I hope that this helped you ;)