Avodos Requiring Kohen

Yoma 26-28 teaches certain main concepts concerning the avodah in the Bais HaMikdash are derived from the first chapter of VaYikra

Ritual Slaughteringושחט את בן הבקר (א,ה)
No mention of a Cohen
Shechting can be done by anyoneReceiving the Bloodוהקריבו בני אהרן הכהנים את הדם וזרקן את הדם על המזבח (א,ה)
The other three main types of service (receiving the blood, transferring and sprinkling on the altar) require a CohenSkinning & Cutting into Piecesוהפשיט את העולה וניתח (א,ו)
ונתנו בני אהרן הכהן אש על המזבח וערכו עצים על האש (א,ז)
Initial thought: Cohen only required placement on the fire, but skinning & cutting into pieces can be done by a non-Cohen
Final decision: Can not learn to other items from the requirement of a Cohen for the fire, since this is not a main avodah, and thus, necessary to specify the CohenArranging the Pieces on the Altarאת הכהנים אהרןבני וערכו הנתחים (א,ח)
Six Cohanim required to arrange the limbs of the Tamid (Daily Offering)* on the Altar
2 – וערכו, 2- בני אהרן 2 - הכהניםFinal Step of the Burnt-Offering of Cattleוהקטיר הכהן את הכל המזבחה (א,ט)
The offering on the Altar requires a Cohen
However, the skinning and cutting into pieces can be done by a non-CohenFinal Step of the Burnt-Offering of Sheepוהקריב הכהן את הכל (א,יג)
A Cohen is required to bring the limbs of the animal to the Altar
A non-Cohen can bring of the blocks of wood
A Cohen is required to arrange the blocks of wood on the Altar

* Even though the Daily Offering is done with a sheep yet the first section of VaYikra mentions cattle. However, since this section concerns the general concepts of lighting the fire and arranging the wood on the Altar, the Rabbis understood that this concept also applies to the Daily Offering.