Survey
* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project
Download Mitosis Powerpoint
Document related concepts
Transcript
TOPICS COVERED • The Cell Cycle • Mitosis – A Detailed Look THE CELL CYCLE Cell Cycle: This represents the processes ________ that occur between one cell division and the ____ next cell division in a cell’s life. __________ three main stages and can be represented in • This involves _____ a pie chart: • The size of each pie 1) Interphase 2) Mitosis 3) Cytokinesis interphase slice roughly represents how much time ____ a cell stays in each part of the cell cycle, but there are great variations depending on the type of cell. THE CELL CYCLE INTERPHASE: The cell spends most of its life here performing its specialized functions and then ________ prepares for cell division _________________ when the time comes. Interphase is broken down into _____ three stages: 1) G1 Phase (Gap1): • The cell grows _____ after division to reach full size (it may double in size). G1 interphase THE CELL CYCLE INTERPHASE: The cell spends most of its life here performing its specialized functions and then ________ prepares for cell division _________________ when the time comes. Interphase is broken down into _____ three stages: 1) G1 Phase (Gap1): • The cell grows _____ after division to reach full size (it may double in size). • The cell performs its specialized function depending on what type _______ of cell it is. G1 interphase bone cell neuron (brain cell) skeletal muscle cell heart muscle cell white blood cell THE CELL CYCLE INTERPHASE: The cell spends most of its life here performing its specialized functions and then ________ prepares for cell division _________________ when the time comes. Interphase is broken down into _____ three stages: 1) G1 Phase (Gap1): • This is the longest ______ part of the cell cycle for most cells except for fast embryonic cells and cancer dividing _________ _____ cells. QUICK TASK #3 G1 interphase There are some cells that speed through G1 very quickly and don’t spend much time, if any, performing specialized functions before they divide again. Can you guess what type of cells these would be? THE CELL CYCLE INTERPHASE: The cell spends most of its life here performing its specialized functions and then ________ prepares for cell division _________________ when the time comes. Interphase is broken down into _____ three stages: 1) G1 Phase (Gap1): • Once organisms reach adulthood, divide some of their cells will never __________ again. These cells stop progressing through the cell cycle and go into G _________________ 0 Phase (Gap Zero) where they will simply continue to perform their functions until they die. neuron (brain cell) heart muscle cell G1 interphase skeletal muscle cell THE CELL CYCLE INTERPHASE: The cell spends most of its life here performing its specialized functions and then ________ prepares for cell division _________________ when the time comes. Interphase is broken down into _____ three stages: 2) S Phase (Synthesis): • The DNA is _________ ___ replicated creating two identical _______ copies of each chromosome. pair also • As well, the centriole ___________ duplicates to create ____ two pairs. _________ 1 centriole pair 1 set of chromosomes G1 interphase 2 centriole pairs 2 sets of chromosomes S THE CELL CYCLE INTERPHASE: The cell spends most of its life here performing its specialized functions and then ________ prepares for cell division _________________ when the time comes. Interphase is broken down into _____ three stages: 3) G2 Phase (Gap2): prepares for mitosis by • The cell ________ growth of its undergoing rapid _______ cytoplasm. • The cell increases the synthesis of the proteins _______ needed to make the spindle fibers used in mitosis. ____________ G1 interphase G2 S • The DNA is checked for replication errors that may have occurred ______ during DNA replication in S Phase. QUICK TASK #4 What occurs if replication errors are left undetected and unfixed before mitosis? Mutations! THE CELL CYCLE INTERPHASE: The cell spends most of its life here performing its specialized functions and then ________ prepares for cell division _________________ when the time comes. Interphase is broken down into _____ three stages: 3) G2 Phase (Gap2): prepares for mitosis by • The cell ________ growth of its undergoing rapid _______ cytoplasm. • The cell increases the synthesis of the proteins _______ needed to make the spindle fibers used in mitosis. ____________ G1 interphase G2 S • The DNA is checked for replication errors that may have occurred ______ mutations during DNA replication in S Phase. This prevents _________ (changes in the DNA code) from being passed to daughter cells. THE CELL CYCLE sorts and divides MITOSIS: This process _____ ______ the duplicated chromosomes identical sets of DNA so that each daughter cell into two ________ gets one set. parent cell Mitosis is needed to sort out these chromosomes. G1 S Phase interphase G2 correct sorting two identical sets of chromosomes in daughter cells S However, mitosis isn’t always perfect… THE CELL CYCLE sorts and divides MITOSIS: This process _____ ______ the duplicated chromosomes identical sets of DNA so that each daughter cell into two ________ gets one set. parent cell Mitosis is needed to sort out these chromosomes. G1 S Phase interphase G2 An error in mitosis has occurred. incorrect sorting two non-identical sets of chromosomes in daughter cells S THE CELL CYCLE sorts and divides MITOSIS: This process _____ ______ the duplicated chromosomes identical sets of DNA so that each daughter cell into two ________ gets one set. four main stages Mitosis is broken down into ____ and they can be represented by the P.M.A.T. which stands for… acronym _______ However, the events that occur between ________ prophase and metaphase _________ are important enough to create a fifth stage between these two called prometaphase ____________. G1 Metaphase interphase G2 S After mitosis divides the nuclear contents into two parts, it’s time to divide the cytoplasm… THE CELL CYCLE cytoplasm in half to CYTOKINESIS: The process that divides ______ the _________ separate daughter cells. create two ________ Animal Cells • In animal cells, a cleavage furrow ______________ forms to constrict the cell membrane in the middle of the cell and divide it. Metaphase interphase G2 Sanddollar cytokinesis cleavage furrow PLAY G1 S THE CELL CYCLE cytoplasm in half to CYTOKINESIS: The process that divides ______ the _________ separate daughter cells. create two ________ Plant Cells • In plant cells, the cell wall makes _______ cytokinesis more challenging. • Instead of making a cleavage furrow, a plant cell makes a cell plate in the ________ middle of the cell. cell plate G1 Metaphase interphase G2 S THE CELL CYCLE cytoplasm in half to CYTOKINESIS: The process that divides ______ the _________ separate daughter cells. create two ________ Plant Cells • The cell plate is made up of vesicles ______ which contain the material needed to wall build the cell _______. fuse • The vesicles ____ at the midline of the cell to create a new cell wall which completely separates ________ the two daughter cells. G1 Metaphase interphase G2 S • Stop and Complete Activity 3.3.1 Part II – Preparation for Mitosis MITOSIS – A DETAILED LOOK G1 Interphase • In this example, we will examine a cell chromosomes (red, blue and containing 3_____________ green) in the initial parent cell. G2 Interphase • After S Phase, each chromosome has undergone DNA replication. There are now 3 duplicated chromosomes _______________________. • At this point, the DNA has _____________ not condensed yet so it is still ____ long and ____. thin This long _________ thread-like form of DNA is called _________. chromatin MITOSIS – A DETAILED LOOK G2 Interphase MITOSIS – A DETAILED LOOK G2 Interphase • The two identical sides of each duplicated chromosome are called _______________. sister chromatids • The two sister chromatids are _________ connected together at a region of the chromosome called the centromere __________. • The centromere is where • microtubules protein structures called ___________ kinetochores assemble on either side of the sister chromatids. The kinetochores are the attachment for sites of __________ ___________ which pull ___ the kinetochores microtubules sister chromatids apart. sister chromatids centromere MITOSIS – A DETAILED LOOK G2 Interphase • The two identical sides of each duplicated chromosome are called _______________. sister chromatids • The two sister chromatids are _________ connected together at a region of the chromosome called the centromere __________. spindle fibers / microtubules • Microtubules ___________ are protein filaments that serve various different functions within a cell. When they are used in mitosis or meiosis, they can be specifically referred to spindle fibers as ____________. kinetochores sister chromatids centromere MITOSIS – A DETAILED LOOK G2 Interphase • The centriole ___________ pair along with the _______ proteins centrosome which that surround it form the __________ is the organelle responsible for _________ microtubules organizing the ___________. animal Centrosomes are only found in ______ cells. centrosomes replicated in S Phase • Along with the DNA, the centrosome is _________ to produce the two centrosomes you see in G2. Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK PROPHASE nuclear membrane • The centrosomes begin to _______ migrate to opposite poles _____________. Spindle fibers begin • ____________ to form between the two centrosomes. membrane begins to dissolve • The nuclear ________________ _______ Why do you think the nuclear membrane needs to dissolve completely? QUICK TASK #5 Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK PROPHASE nuclear membrane • The centrosomes begin to _______ migrate to opposite poles _____________. Spindle fibers begin • ____________ to form between the two centrosomes. nucleolus membrane begins to dissolve • The nuclear ________________ _______ frees the chromosomes to be sorted which _____ and divided in later stages of mitosis. condense and • The chromatin begins to ________ visible become shorter ______ , thicker ______ and ______. • The nucleolus ________ begins to disappear. Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK PROMETAPHASE Compare prometaphase to prophase. What changes have occurred? QUICK TASK #6 Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK PROMETAPHASE equatorial plate • The nuclear membrane is ______ almost completely dissolved which allows fibers access the spindle ___________ to the duplicated chromosomes. kinetochore spindle fibers • The nucleolus ________ has disappeared. • Kinetochore __________ spindle fibers reach through the dissolving nuclear membrane and attach to the ___________ kinetochores of each ______ duplicated chromosome. These spindle position the duplicated fibers begin to _______ chromosomes along the midline of the cell equatorial (or metaphase) plate called the _________ ____. Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK PROMETAPHASE equatorial plate • The nuclear membrane is ______ almost completely dissolved which allows fibers access the spindle ___________ to the duplicated chromosomes. astral spindle fibers kinetochore spindle fibers polar spindle fibers • Polar ____ spindle fibers from opposite poles reach the midline and push against one extend the distance between another to ______ the two centrosomes. Astral spindle fibers help ______ anchor the • _____ centrosomes at opposite poles of the cell. Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK PROMETAPHASE equatorial plate • The nuclear membrane is ______ almost completely dissolved which allows fibers access the spindle ___________ to the duplicated chromosomes. astral spindle fibers kinetochore spindle fibers polar spindle fibers • All of the different types of spindle fibers help form a network of fibers called the spindle apparatus (or _____________). mitotic spindle _______________ Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK METAPHASE Compare metaphase to prometaphase. What changes have occurred? QUICK TASK #7 Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK METAPHASE • The centrosomes are ____ fully migrated to opposite poles. • The spindle apparatus is completely _________ formed. fully dissolved. • The nuclear membrane is ____ lined up the • The spindle fibers have _______ duplicated chromosomes along the equatorial plate so that each sister _____________ chromatid of a duplicated chromosome faces opposite _______ poles. Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK METAPHASE • The centrosomes are ____ fully migrated to opposite poles. • The spindle apparatus is completely _________ formed. alignment at this stage helps to • Correct _________ ensure that each new daughter cell will receive one sister chromatid from each duplicated chromosome when the sister chromatids are separated. Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK METAPHASE • At this stage, the chromosomes are thick ____, _____ short and at their most condensed _________, hence the chromosomes are at their most easily observable state. sister chromatid centromere Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK ANAPHASE Compare anaphase to metaphase. What changes have occurred? QUICK TASK #8 Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK ANAPHASE • Each chromatid becomes its own ___________ chromosome once separation has occurred. shorten • The kinetochore __________ spindle fibers _______ and ____ pull the attached sister chromatids apart at the __________ centromere towards opposite poles. • The polar ____ spindle fibers push against each other to elongate _______ the cell and further separate the sister chromatids. Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK TELOPHASE Compare telophase to anaphase. What changes have occurred? QUICK TASK #9 Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK TELOPHASE • This phase is essentially the reverse ______ of prophase. • The spindle apparatus begins to disassemble __________. • The chromosomes become ____ long and thin decondensing and reverting ___ by ____________ chromatin structure. back to their _________ membrane begins to reform • A nuclear ________________ around each set of chromosomes. • The nucleolus ________ reappears in each nucleus. Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK TELOPHASE cleavage furrow furrow (or ________ cell plate in • A cleavage _____________ plant cells) begins to form which signals the beginning of __________ cytokinesis which will separate the two new daughter cells. Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK Real cells are harder to identify! prophase metaphase prometaphase telophase interphase anaphase How many did you get correct? Identify cells A-F as interphase, prophase, prometaphase, metaphase, anaphase or telophase. ACTIVITY #1 Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK prophase A anaphase B telophase C interphase D metaphase E How many did you get correct? ACTIVITY #2 Identify cells A-E as interphase, prophase, metaphase, anaphase or telophase. (There’s no prometaphase example in this image.) Telophase MITOSIS ProAnaphase Metaphase metaphase Prophase MITOSIS – A DETAILED LOOK Mitosis (Overview) PLAY The Cell Cycle and Mitosis (Detailed) PLAY
