Lecture 2 - Jan 11, 2010

Lecture 2 - Jan 11, 2010 - 9.3 What Happens during Mitosis?...

Info iconThis preview shows pages 1–15. Sign up to view the full content.

View Full Document Right Arrow Icon
9.3 What Happens during Mitosis? Centrosome is made of 2 centrioles Centromere
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
9.3 What Happens during Mitosis? At G2 to M transition, the centrosomes move to opposite ends of the nuclear envelope. Orientation determines the plane at which the cell will divide; and the spatial relationship of the two new cells.
Background image of page 2
9.3 What Happens during Mitosis? Mitosis can be divided into phases: Prophase Prometaphase Metaphase Anaphase Telophase
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
9.3 What Happens during Mitosis? Prophase: cohesin disappears chromatids become visible. Kinetochores develop at centromere regions. Centrosomes serve as poles; microtubules form the spindle .
Background image of page 4
9.3 What Happens during Mitosis? Spindle has two types of microtubules: Polar microtubules — overlap in center. Kinetochore microtubules —attach to kinetochores on the chromatids. Sister chromatids attach to opposite halves of the spindle.
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Figure 9.9 The Mitotic Spindle Consists of Microtubules (Part 1)
Background image of page 6
9.3 What Happens during Mitosis? Prometaphase Nuclear envelope and nucleoli disappear. Chromosomes are gradually pushed towards the equatorial plate .
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Figure 9.10 Mitosis (Part 1)
Background image of page 8
9.3 What Happens during Mitosis? Metaphase : all centromeres align at the equatorial plate. The Metaphase-Anaphase transition (spindle) checkpoint If all kinetochores are attached to spindle fibers – only then events to separate chromatids initiated
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Figure 9.11 Chromatid Attachment and Separation Separase activated Separase inhibited by securin
Background image of page 10
9.3 What Happens during Mitosis? Anaphase : Degradation of securin activates separas e Cohesin is hydrolyzed by separase . The sister chromatids separate and move to opposite ends of the spindle Chromatid is now referred to as daughter chromosome
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
9.3 What Happens during Mitosis? How do chromosomes move to poles? Kinetochore motor proteins Shortening of microtubules
Background image of page 12
9.3 What Happens during Mitosis? Telophase : Spindle breaks down Chromosomes uncoil Nuclear envelope and nucleoli are reformed Two daughter nuclei are formed with identical genetic information
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
How does the cell stretch apart?
Background image of page 14
Image of page 15
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/18/2010 for the course BIOSC Bio 210 taught by Professor Deshmukh during the Spring '10 term at Pittsburgh.

Page1 / 57

Lecture 2 - Jan 11, 2010 - 9.3 What Happens during Mitosis?...

This preview shows document pages 1 - 15. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online