Loading presentation...

Present Remotely

Send the link below via email or IM

Copy

Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

DeleteCancel

Make your likes visible on Facebook?

Connect your Facebook account to Prezi and let your likes appear on your timeline.
You can change this under Settings & Account at any time.

No, thanks

Biology- Mitosis and Meiosis

No description
by

Erica Kim

on 30 October 2012

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Biology- Mitosis and Meiosis

Mitosis & Meiosis MITOSIS Mitosis MEIOSIS MEIOSIS http://www.diffen.com/difference/Meiosis_vs_Mitosis MEIOSIS vs MITOSIS BY. Erica Sojeong Kim and Sera J. Lee Mitosis is the type of division in which the daughter cell receives the exact number of chromosomes as the parent cell. Cell Division and reproduction can occur in different processes; mitosis and meiosis. The first part of the cell theory states that all living things are made up of one or more cells and that all cells are from pre-existing cells from cell division. Through Mitosis the nucleus duplicates its DNA and the two new cells (daughter cells) have the same pieces and the genetic code. The two copies descend from the original. There are five key stages of mitosis. 2. PROPHASE- The chromosomes condense and the centrioles move to opposite poles of the cell and spindle fibres start to form. The centrioles assemble and spindle fibres attatch to the centromeres of the chromosomes. The nuclear membrane starts to dissolve. 1. INTERPHASE- refers to all stages of the cell cycle other than mitosis. During interphase, cellular organelles double in number, the DNA replicates, and protein synthesis occurs. The chromosomes are not visible and the DNA appears as uncoiled chromatin. 3. METAPHASE- Chromosomes line up at the equatorial plate. The nuclear membrane completely dissolves. 4. ANAPHASE- The centromeres divide and the chromosomes, formerly chromatids, move to opposite poles of the cell. An identical set of chromosomes moves to each pole. 5. TELOPHASE- Chromosomes lengthen again, the spindle fibres dissolve, and a nuclear membrane forms around the chromosomes. In humans, each new nucleus contains 46 unique chromosomes. 6. CYTOKINESIS- Once the chromosomes have moved to opposite poles the cytoplasm begins to divide. In an animal cell, a furrow develops, pinching off the cell into two parts. In plant cells, the separation is accomplished by a cell wall that forms between the two chromatin masses. http://biology.uoregon.edu/reference/ort_mitosis/interphase.html Meiosis is the process by which sex cells or gametes are formed. In humans, the process takes place in the testes and ovaries. The number of chromosomes in a gamete is called the haploid chromosome number. The number of chromosomes in all other cells is twice the haploid number and is called the diploid number. In humans, the haploid chromosome number is 23 and the diploid chromosome number is 46. Each of the 23 chromosomes that you receive from your father is matched by 23 chromosomes from your mother. The paired chromosomes are called homologous chromosomes because they are similar in shape, size and gene arrangement. http://biology.clc.uc.edu/courses/bio104/meiosis.htm INTERPHASE- is the same in both mitosis and meiosis. In meiosis, it is followed by two cell divisions. These two division processes are referred to as Meiosis I and Meiosis II. MEIOSIS I PROPHASE I- the replicated chromosomes will come together and match up (synapsis) in pairs (tetrads). Crossing over occurs and chromosomes attatch to the spindle fibres. METAPHASE I - Chromosomes line up at the equatorial plate (along the middle). ANAPHASE I - Each chromosome separates from its homologous pair. They move to opposite poles of the cell. TELOPHASE I - The nucleus completes its division. The chromosomes are still composed of sister chromatids. The cytoplasm divides after telophase. MEIOSIS II PROPHASE II- The centrioles in a two new cells move to opposite poles and new spindle fibres form. The chromosomes become attatched to the spindle fibres. METAPHASE II- Chromosomes line up at the equatorial plate (along the middle). ANAPHASE II- Sister chromatids of each chromosome separate and move to opposite poles. TELOPHASE II- The cytoplasm of each cell divides once again, resulting in four haploid daughter cells. The chromosome number has been reduced by half and the cells may become gametes. QUIZ! Lets see how much you know about these two cell divisions!!!!! 1. How do haploid and diploid differ? Mitosis Song http://www.uic.edu/classes/bios/bios100/lecturesf04am/lect16.htm Textbook: pg. 103-107, pg. 88-92 1. Diploid cells (2N) have two complete sets of chromosomes. The body cells of animals are diploid.Haploid cells have one complete set of chromosomes. In animals, gametes (sperm and eggs) are haploid. 2. What is the importance of crossing over in meiosis? 2. Crossing over promotes variation. During prophase of meiosis, crossing-over results in chromosomes that have some genes from one parent and some genes from the other parent, making each individual unlike any other individual and unique. 3. a) If the parent cell starts out with 24 Chromosome and undergoes mitosis, then how many will the daughter cells have? 3. a) 24
3. b) In Meiosis if the parent cells has 40 chromosomes, then how many will the daughter cells have? 3. b) 20 THEN IT GOES AGAIN CUZ ITS MITOSIS
CUZ THE CELL SPLIT ONCE

NOW THE CELL SPLITS TWICE
WE GON SPLIT THIS CELL, CUZ ITS MITOSIS I COME TO SPLIT SPLIT SPLIT SPLIT
THERE ARE 4 PHASES IN THIS PLAN PLAN PLAN PLAN
WE ALWAYS START AND NEVER STOP STOP STOP STOP
CAUSE THIS PROCESS IS MI TO TO TO SIS

YEAH YEAH CAUSE IT GOES ON AND ON AND ON
AND IT GOES ON AND ON AND ON

YEAH MY CHROMATIDS COIL AT THE CENTROMERE
THIS IS PROPHASE, THE FIRST PHASE
THE CENTRIOLES GO TO BOTH THE ENDS
IN THIS PHASE, CALLED PROPHASE

WE GON SPLIT THIS CELL, WE GON SPLIT ALL NIGHT
WE GON SPLIT IT UP, CUZ ITS MITOSIS

CUZ THE CELL SPLIT ONCE
NOW THE CELL SPLITS TWICE
WE GON SPLIT THIS CELL, CUZ ITS MITOSIS CHROMOSOMES START TO MOVE MOVE MOVE MOVE
TO THE MIDDLE OF THE CELL CELL CELL CELL
THE SPINDLE FIBRES START TO BOND BOND BOND BOND
IN METAPHASE ITS WHAT THEY DO DO DO DO

YEAH YEAH
CAUSE IT GOES ON AND ON AND ON
AND IT GOES ON AND ON AND ON

YEAH THE NEXT THING THAT COMES IS ANAPHASE
WHERE THEY PULL APART AND THEY START TO SPLIT THE SPINDLE FIBRES START TO DISSAPEAR
THIS IS TELOPHASE, THE VERY LAST PHASE
THE ENVELOPE REAPPEARS IN THIS ONE LAST PHASE THANK YOU
Full transcript