❖ Cilium or Flagellum movement using axonemal dynein
➢ The MT doublets here bend
➢ Cilia wave back and forth and are shorter
➢ Flagellum whip and are longer
❖ Cell Theory
➢ Cells fundamental unit of life
➢ All organisms are made of one or more cells
➢ All cells arise from preexisting cells
❖ Cell cycle procedure
➢ Cell grows
➢ DNA replication
➢ Distribution of replicated Xsomes
➢ Cell division
➢ In bacteria:
■ Growth and DNA replication happen throughout the cell’s life
➢ In Eu:
■ Growth is continuous but DNA rep only occurs in one part of the cell’s
❖ Eu cell cycle
➢ Based on human cells (for the purposes of MCB 150)
■ Divides every 24 hours (on AVG)
■ M phase (5%) and interphase (95%)
● M phase = mitosis and cytokinesis
■ DNA rep is in S phase
➢ Phases: G1, S (continuation of G1 PLUS DNA rep), G2, M (Mitosis and Cyto)
❖ NOTE: in M phase, the cell is still one cell until the end of cytokinesis so DNA M =
❖ LC question
If a human cell has a 2n amount of DNA during G1, it has:
Choose all that apply.
● a 2n amount of DNA during G2.
● an n amount of DNA during M-phase.
● a 4n amount of DNA during G2.
● a 2n amount of DNA during M-phase.
● a 4n amount of DNA during M-phase.
● an n amount of DNA during G2
❖ Time spent in each phase depends on the organism
➢ Cultured Human cells
■ 11 hrs in G1 ■ 8 hrs in S
■ 4 hrs in G 2
■ 1 hr in M
➢ Yeast cells