Common Ancestry of Cells
Ailee – Higher (Feat. Yiruma) by DEARWISH14
Enjoy some music while viewing; this song can apply to evolution! :)
Endosymbiosis [HD Animation]
Erythrocyte (RBCs) (for Humans)
- No nucleus or other membrane bound organelles
- Cell membrane
- An RBC has a strange shape -- a biconcave disc that is round and flat, sort of like a shallow bowl.
- An RBC can change shape to an amazing extent, without breaking, as it squeezes single file through the capillaries. (Capillaries are minute blood vessels through which oxygen, nutrients and waste products are exchanged throughout the body.)
- An RBC contains hemoglobin, a molecule specially designed to hold oxygen and carry it to cells that need it.
- The primary function of red blood cells is to transport oxygen from the lungs to the cells of the body. RBCs contain a protein called hemoglobin that actually carries the oxygen.
- Human erythrocytes are produced through a process named erythropoiesis, developing from committed stem cells to mature erythrocytes in about 7 days.
- When matured, in a healthy individual these cells live in blood circulation for about 100 to 120 days (and 80 to 90 days in a full term infant). At the end of their lifespan, they become senescent, and are removed from circulation.
- Cytoplasmic lipid membrane
- No membrane-bound organelles
- Thick peptidoglycan layer
- Teichoic acids and lipoids are present, forming lipoteichoic acids, which serve as chelating agents, and also for certain types of adherence.
- Peptidoglycan chains are cross-linked to form rigid cell walls by a bacterial enzyme DD-transpeptidase.
- Cocci shaped