The three gunas are the three modes of workings of Nature related to her three movements of creation, preservation, destruction.
Sattwic mode helps in equilibrium and preservation.
Rajasic mode helps in dynamism, creation, action. It impels us to act.
Tamasic mode leads to inertia and disintegration due to lack of progressive forward movement.
All three operate everywhere and in everything. They are needed to keep the cycle of creation going.
When we are dynamic then rajas is active. When we are sleepy and tired then tamas is active. When we seek balance and harmony then Sattwa is needed.
Yonis are earthly species subject to birth and death.
Mukti is Freedom from a blind and mechanical subjection to this cycle of nature.
Affectionately,
Alok Da