Mitosis and Meiosis Asexual Reproduction and the Cell Cycle Biology Fall 2012

Bell Ringer 1. What is the difference between prokaryotes and eukaryotes? 2. Do all cells divide in the same manner?

Objectives  Define asexual reproduction  Identify the major events that characterize each of the 5 phases of the cell cycle  Describe how the cell cycle is controlled in eukaryotic cells

Formation of New Cells  About 2 _______________ cells are produced by an adult human body every ____________  New cells are __________ when older cells ________  Cell division, aka cell reproduction

Formation of New Cells  Different types of cell division  _________________: bacteria reproduce ______________  Eukaryotes:  ________________________: undergo growth, development, repair, or asexual reproduction  ________________________: formation of gametes  Asexual reproduction: mode of reproduction by which ______________________ arise from a _______________ parent, and inherit the __________ of that parent only

Formation of New Cells  Regardless of the type of cell division occurring, information stored in ________ must be ________________ in each of the resulting _____________  DNA directs cells ___________________and determines its characteristics  When a cell divides, DNA is ___________ copied and then distributed  Each cell ends up with a ___________________ set of the DNA

Prokaryotic Cell Division  DNA- ________________________, attached to inner cell membrane  Reproduce by binary fission  ____________________________: form of asexual reproduction that produces ______________ offspring  Single parent passes exact copies of all of its DNA to its offspring

Prokaryotic Cell Division Binnary Fission Stages: 1. ______________________________ 2. ______________________________  Adds new cell membrane to the point on the membrane between the two DNA copies  New cell wall forms around membrane  Pinch in two

The Life of a Eukaryotic Cell  Cell division in ________________________ is more ____________________ than in prokaryotes  Involves cytoplasm, chromosomes inside nucleus, and internal organelles

The Cell Cycle  __________________: repeating sequence of cellular growth and division during the life of an organism  A cell spends ________ of its time in the first three phases of the cycle  _______________________________________  Only enters the last two phases of cycle if it’s about to ______________________

Cell Cycle

The Cell Cycle  Phase #1: __________________________________  Cell _____________ rapidly and caries out routine functions  Occupies major portion of cells life  Cells that are not dividing _________________ in G1 phase  Most _________________ and _______________ cells never divide  If these cells die the body cannot replace them

The Cell Cycle  Phase #2: __________________________________  Cell’s __________ is __________________  At the end of the phase, each chromosome consists of two chromatids attached at the centromere  Diagram:

The Cell Cycle  Phase #3: __________________________________  Preparations are made for the ______________________ to divide  Hollow protein fibers called _________________________ are rearranged during G2 in preparation for ________________________

The Cell Cycle  Phase #4: __________  Mitosis: ____________ of a cell is divided into ________ nuclei  Each nucleus ends up with the _____________ number and kinds of ____________________ as the _______________ cell

The Cell Cycle  Phase #5: __________________________________  Cytkinesis: the process during cell division in which the _________________________ divides

Cell Cycle

The Cell Cycle  ____________________ and ___________________ produce new cells that are _____________________ to the original cells  Allows organisms to _________________, replace damaged tissues, and in some organisms reproduce __________________________

Control of the Cell Cycle  Realize that cells have a system that ____________________ the phases of the cell cycle  A cell can _________ at certain points of the cell cycle depending on cellular and environmental conditions

Review  Draw a pie diagram that outlines the cell cycle.  Include:  Each of the names of the cell cycle phases  A brief description of what is occurring during each phase  Label the three phases that make up interphase  Bonus points for colouring!