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Pill

Theme C - Interaction &  Interdependence

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Direct Hit

Theme A - Unity & Diversity

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Page Facing Up

Theme B - Form & Function

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Keycap Digit One

Theme D - Continuity & Change

🌱 Intro to Autotrophs: Autotrophs are the cool cats of the biological world. They whip up their own food, just like a chef in a kitchen! But instead of stoves and ovens, they use other energy sources. Let&#39;s break down how!

<ul>
	<li>Autotrophs need an external energy source to create carbon compounds.</li>
	<li>Why? Carbon in CO2 or hydrogen carbonate ions is like a lazy couch potato, oxidized and not ready to move. Getting it to work requires energy!</li>
</ul>

<ul>
	<li>Photoautotrophs: These are the sun-lovers. They use light as their energy source. Think plants sunbathing!
	<ul>
		<li>Example: 🌻Plants, algae, and cyanobacteria.</li>
	</ul>
	</li>
	<li>Chemoautotrophs: The chemists in the group. They use energy from inorganic chemical reactions.
	<ul>
		<li>Example: Some nifty prokaryotes like certain bacteria and archaebacteria.</li>
	</ul>
	</li>
</ul>

🌏 Fun Fact: Only a teeny-tiny bit of sunlight reaches Earth, and even less is used for photosynthesis. But this sliver of sunshine powers most ecosystems!

<ul>
	<li>Iron-oxidizing bacteria: These are some iron-loving chemoautotrophs.
	<ul>
		<li>They party with iron sulfide (FeS2), found in some rocks.</li>
		<li>When these rocks say hi to air (thanks to stuff like mining), the iron sulfide does a chemical dance, leading to Fe2+ ions, sulfate ions, and some pretty sour sulfuric acid.</li>
		<li>Reaction looks like this: <code>FeS2 + 3&frac12;O2 + H2O &rarr; Fe2+ + SO4 2&minus; + H2SO4</code></li>
	</ul>
	</li>
	<li>Then, the iron-oxidizing bacteria step in, taking away electrons from the Fe2+ ions, making them Fe3+ ions. This electron stealing helps produce energy.
	<ul>
		<li>It&#39;s a bit like stealing batteries from a remote!</li>
	</ul>
	</li>
	<li>These bacteria use these stolen electrons in a couple of cool ways
	<ul>
		<li>Reducing NAD, an important molecule. <code>2Fe2+ + NAD + 2H+ &rarr; 2Fe3+ + reduced NAD</code></li>
		<li>Boosting energy by making ATP via a process called chemiosmosis. <code>2Fe2+ + &frac12;O2 + 2H+ &rarr; 2Fe3+ + H2O</code></li>
	</ul>
	</li>
	<li>With their stash of NAD and ATP, these bacteria fix carbon dioxide to make their own food via the Calvin cycle.</li>
</ul>

🔬 Microbe Spotlight: Acidithiobacillus ferrooxidans

<ul>
	<li>This iron-oxidizing bacterium loves to chill in very acidic places. Why? Because the reactions it&#39;s involved in make sulfuric acid. Talk about thriving in a tough neighborhood!</li>
</ul>

🌍 Real-world application: Understanding these energy processes is vital, especially as we explore sustainable energy options. Chemoautotrophs, for example, have potential applications in bio-mining, where they can help extract metals from ores.

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And there you have it! The incredible ways autotrophs, both sun-lovers and chemical-maestros, get their energy. So, the next time you see a plant or think about bacteria, remember the intricate dances they&#39;re doing to make their meals! 🌿🔬🌞

Unlocking Energy Light in Photoautotrophs, Oxidation in Chemoautotrophs

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Standard Level

Biology SL

Theme C - Interaction & Interdependence

Unlocking Energy Light in Photoautotrophs, Oxidation in Chemoautotrophs

Table of content

Energy Needs of Autotrophs

Unlock the Full Content!

Theme C - Interaction & Interdependence

Unlocking Energy Light in Photoautotrophs, Oxidation in Chemoautotrophs

Table of content

Energy Needs of Autotrophs

Unlock the Full Content!