This increase in volume leads to a decrease in intra-alveolar pressure, creating apressure<span> lower than atmospheric </span>pressure<span>. As a result, a </span>pressure<span> gradient is created that drives air into the </span>lungs<span>. Figure 3. </span>Inspiration<span> and expiration </span>occur<span> due to the expansion and contraction of the thoracic cavity, respectively.
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Bacteria and restriction enzymes
,use enzymes to cut (and thereby destroy) foreign DNA (such as viral DNA), which would restrict the growth of the virus; own DNA is protected in some way (often by addition of methyl group CH3) to the sequence recognized by enzyme (thus preventing enzyme from binding there)
Fox are shown as secondary and tertiary consumers
