<span>(4) active transport
</span>Active transport is the movement of molecules across a cell membrane in the direction against their concentration gradient, i.e. moving from an area of lower concentration to an area of higher concentration.
Answer:
Gated ion-channels
Explanation:
These ion channels are protein molecules that act as a passageway which span across the cell membrane allowing the movement of ions from one side of the membrane to the other. They possess the ability to open and close in response to either chemical or mechanical signals.They possess a fluidic pore, which becomes available to ions after a conformational change in the protein structure has been activated causing the ion channel to open. Based on the stimulus to which they respond, ion channels are divided into three groups: voltage-gated, ligand-gated and mechano-sensitive ion channels. Channels responding to electrical (voltage-dependent ion channels), mechanical, or chemical (ligand-gated ion channels) stimuli open and allow rapid ion movement into or out of the cell, and this movement creates an electrical signals.
Answer:
C. The high concentration of hydrogen ions in the intermembrane
Explanation:
Merry Christmas
Semen creates a(n)<u>alkaline </u>environment for sperm to safely travel through both the male and female reproductive tracts.
In the field of biology, semen can be described as a white, slippery fluid that is released from the male reproductory organ. Semen is also referred to as the seminal fluid.
The semen of males carries the sperm cells which are required for the fertilization of the female egg. The conditions should be favorable for the process of fertilization to occur.
The natural atmosphere of the vagina of a female is acidic in nature. The sperms need a neutral environment for survival. Hence, the semen is produced alkaline in nature to prolong the lifetime of sperm cells. The alkalinity of the semen neutralizes the acidity of the vagina.
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