LESSON 1: CELL CYCLE

CELL DIVISION

PROCESS WHERE ONE CELL DIVIDES TO PRODUCE NEW CELLS

CELL DIVISION

IMPORTANT BIOLOGICAL PRINCIPLE FORMULATED BY RUDOLF VIRCHOW IN 1858

CELL DIVISION

STATES THAT ALL CELLS COME FROM OTHER CELLS

CELL DIVISION

IT’S SIMPLE YET PROFOUND

CELL DIVISION

TELLS US THAT LIFE ITSELF IS PERPETUATING

CELL DIVISION

THIS PROCESS OF CELLULAR REPRODUCTION IS COMMONLY KNOWN AS ________________

CELL DIVISION

ENABLES A MULTICELLULAR ORGANISM TO GROW AND REACH THE ADULT SIZE

CELL DIVISION

REPLACES WORN OUT OR DAMAGED CELLS

CELL DIVISION

KEEPS THE TOTAL NUMBER CELLS IN AN ADULT ORGANISM RELATIVELY CONSTANT

CELL CYCLE

THE ENTIRE SERIES OF STAGES A CELL GOES THROUGH AS IT GROWS, COPIES ITS DNA, AND PREPARES TO DIVIDE

INTERPHASE, MITOSIS, CYTOKINESIS

THREE CELL CYCLES

INTERPHASE

LASTS FOR AT LEAST 90% OF TOTAL TIME REQUIRED FOR THE CELL CYCLE FOR MOST CELLS

INTERPHASE

CELL MAY APPEAR RESTING UNDER THE MICROSCOPE, BUT IT GOES THROUGH A PERIOD OF VERY HIGH METABOLIC ACTIVITY

INTERPHASE

CHROMOSOMES DUPLICATED

INTERPHASE

MANY CELL PARTS ARE MADE

INTERPHASE

THE CELL DOES MOST OF ITS GROWING

INTERPHASE

THE PERIOD WHEN THE CELL GROWS, PERFORMS ITS NORMAL FUNCTIONS, AND COPIES ITS DNA BEFORE DIVISION.

G1 PHASE

THE PERIOD BEFORE DNA SYNTHESIS BEGINS

G1 PHASE

CHARACTERIZED BY AN INCREASE IN THE SUPPLY OF PROTEINS, IN THE NUMBER OF ORGANELLES PARTICULARLY MITOCHONDRIA AND RIBOSOMES, ADND IN THE SIZE OF THE CELL

G1 PHASE

CELL GROWS AND PERFORMS NORMAL FUNCTIONS.

S PHASE

DNA IS COPIED.

S PHASE

CHARACTERIZED MAINLY BY DNA SYNTHESIS OR REPLICATION

S PHASE

THE CELL MAKES ANOTHER COPY OF ITS CHROMOSOMES, WHICH ARE COMPOSED OF THE DNA AS WELL AS THE PROTEINS ATTACHED TO THEM

S PHASE

IDENTICAL COPIES OF EACH CHROMOSOMES THAT RESULT FROM THE REPLICATION CALLED SISTER CHROMATIDS.

SISTER CHROMATIDS

REMAIN ATTACHED TO EACH OTHER AT A POINT CALLED CENTROMERE

SISTER CHROMATIDS

TWO IDENTICAL COPIES OF A CHROMOSOME THAT ARE PRODUCED WHEN DNA IS COPIED.

CENTROMERE

THE REGION OF A CHROMOSOME WHERE SISTER CHROMATIDS ARE JOINED AND WHERE THE KINETOCHORE FORMS FOR SPINDLE ATTACHMENT.

CHROMATID

ONE COPY OF A DUPLICATED CHROMOSOME.

G2 PHASE

IT SPANS FROM THE COMPLETION OF DNA SYNTHESIS TO THE START OF ACTUAL CELL DIVISION

G2 PHASE

IT PREPARES THE CELL FOR CHROMOSOMAL SEPARATION.

G2 PHASE

CHARACTERIZED BY THE SYNTHESIS OF MITOCHONDRIA AND RIBOSOMES, THE SYNTHESIS OF MICROTUBULES AND PROTEIN THAT WILL FORM THE MITOTIC SPINDLE FIBERS, AND CHROMOSOMAL CONDENSATION

G2 PHASE

CELL GROWS MORE AND PREPARES FOR DIVISION.

MITOSIS

HAPPENS IN SOMATIC CELLS

MITOSIS

REPRODUCES BODY CELLS

MITO

THE TERM ____ IS DERIVED FROM THE LATIN WORD MEANING "THREADS".

MITOSIS

SCIENTISTS CENTURIES AGO HAD SEEN "THREADS" WITHIN CELLS SO THEY NAMED THE PROCESS OF "THREAD MOVEMENTS" AS MITOSIS.

MITOSIS

THE NUCLEAR MATERIAL BECOMES VISIBLE AS THREAD LIKE CHROMOSOMES DURING MITOSIS.

MITOSIS

THESE CHROMOSOMES ORGANIZE AT THE CELL CENTER AND THEN SEPARATE, MOVING INTO EACH NEW CELL THAT IS FORMED.

MITOSIS

A SERIES OF MODIFICATIONS IS UNDERGONE BY THE NUCLEUS TO FORM DAUGHTER NUCLEI IN THE DIVIDING CELL.

KAROKINESIS

PRODUCES TWO DAUGHTER NUCLEI

KARYOKINESIS

THE EQUAL NUCLEAR DIVISION CALLED ________ IS FOLLOWED BY THE DIVISION OF THE CELL BODY CALLED CYTOKINESIS. THE CELLS WHICH CONSTITUTE THE BODY OR SOMA MULTIPLE BY MITOSIS, HENCE THE PROCESS OF MITOSIS IS DESIGNED AS SOMATIC CELL DIVISION.

KARYOKINESIS

DIVISION OF NUCLEUS

KINESIS

DIVISION

KARYO

NUCLEUS

CYTOKINESIS

DIVISION OF CYTOPLASM

MITOSIS

CELL’S WAY OF MAKING COPIES OF ITSELF

MITOSIS

HAPPENS WHEN A CELL NEEDS TO GROW, REPAIR ITSELF, OR REPLACE OLD OR DAMAGED CELLS

MITOSIS

THE CELL PREPARES FOR ________ BY GETTING READY

MITOSIS

MAKES SURE IT HAS EVERYTHING IT NEEDS TO DIVIDE INTO TWO NEW CELLS

MITOSIS

DIVISION OF THE NUCLEUS THAT PRODUCES TWO GENETICALLY IDENTICAL DAUGHTER CELLS WITH THE SAME CHROMOSOME NUMBER AS THE ORIGINAL CELL.

PROPHASE, METAPHASE, ANAPHASE, TELOPHASE

PHASES OF MITOSIS

PROPHASE

MITOSIS OFFICIALLY BEGINS WITH PROPHASE.

PROPHASE

PREPARATION

PROPHASE

DURING THIS PHASE, THE CHROMATIN, WHICH CONSISTS OF DNA AND PROTEINS, CONDENSES INTO VISIBLE CHROMOSOMES WHICH BECOME MORE TIGHTLY COILED AND FOLDED.

PROPHASE

THE NUCLEOLI DISAPPEAR.

PROPHASE

IN THE CYTOPLASM, THE MITOTIC SPINDLE, WHICH IS COMPOSED OF MICROTUBULES, BEGINS TO FORM FROM THE CENTRIOLES, WHICH AT THE SAME TIME BEGIN TO MOVE AWAY FROM EACH OTHER, TOWARD OPPOSITE SIDES OF THE CELL.

PROPHASE

THE NUCLEAR ENVELOPE BREAKS INTO FRAGMENTS.

PROPHASE

WITH THE NUCLEAR ENVELOPE GONE, SOME OF THE MICROTUBULES EMERGING FROM THE CENTRIOLES REACH THE HIGHLY CONDENSED CHROMOSOMES AND ATTACH TO THE PROTEIN STRUCTURE CALLED KINETOCHORE AT THE CENTROMERE REGION

KINETOCHORE

A PROTEIN STRUCTURE THAT FORMS ON THE CENTROMERE OF A CHROMOSOME AND ATTACHES TO SPINDLE FIBERS.

PROPHASE

CHROMATIN CONDENSES INTO VISIBLE CHROMOSOMES.

PROPHASE

NUCLEAR ENVELOPE BEGINS TO BREAK DOWN.

PROPHASE

SPINDLE FIBERS FORM

METAPHASE

CHROMATIDS LINE UP IN THE MIDDLE OF THE CELL.

METAPHASE

CHROMATIDS BEGIN MOVING TOWARD THE CENTER OF THE CELL AND ALIGN MIDWAY BETWEEN THE SPINDLE POLES, OR ALONG THE SPINDLE EQUATOR

METAPHASE

THE SPINDLE MICROTUBULES ATTACHED TO THE INDIVIDUAL KINETOCHORES PULL THE SISTER CHROMATIDS TOWARD THE CENTER OF THE CELL, WITH EACH CENTROMERE EQUIDISTANT FROM EACH POLE OF THE CELL

METAPHASE

MIDDLE

ANAPHASE

SISTER CHROMATIDS SEPARATE AND MOVE TO OPPOSITE SIDES.

ANAPHASE

AWAY FROM EACH OTHER

ANAPHASE

THE CENTROMERE OF EACH CHROMOSOME DIVIDES, AND THE TWO SISTER CHROMATIDS DETACH FROM EACH OTHER. AS THIS HAPPENS, THE SPINDLE MICROTUBULES SHORTEN, PULLING THE DETACHED SISTER CHROMATIDS TOWARD THEIR RESPECTIVE POLES.

ANAPHASE

EACH CHROMATID IS NOW CONSIDERED A FULL

TELOPHASE

CHROMOSOMES REACH OPPOSITE SIDES.

TELOPHASE

NEW NUCLEAR ENVELOPES FORM AROUND THEM.

TELOPHASE

TWO DAUGHTER NUCLEI PRODUCES

TELOPHASE

SPINDLE FIBERS DISAPPEAR

TELOPHASE

BEGINS AS SOON AS THE DAUGHTER CHROMOSOMES REACH THE OPPOSITE END OF THE POLES.

TELOPHASE

THIS STAGE IS CHARACTERIZED BY THE FORMATION OF A NUCLEAR ENVELOPE AROUND EACH SET OF THE CHROMOSOMES.

TELOPHASE

THE CHROMOSOMES UNCOIL, AND ONCE AGAIN APPEAR THREAD

TELOPHASE

NUCLEOLI REAPPEAR.

TELOPHASE

AT THE END OF THE _________, THE MITOTIC SPINDLES DISAPPEAR AND THE EQUAL DIVISION OF ONE NUCLEUS INTO TWO IDENTICAL DAUGHTER NUCLEI IS COMPLETED.

CYTOKINESIS

DIVIDES THE CYTOPLASM INTO TWO DAUGHTER CELLS

CYTOKINESIS

FINAL STAGE OF THE CELL DIVISION

CLEAVAGE FURROW

IN ANIMAL CELLS, CYTOKINESIS IS CALLED _____________, WHICH PINCHES THE CELL MEMBRANE INWARD UNTIL THE CELL IS DIVIDED INTO TWO

CELL PLATE

IN PLANT CELLS, CYTOKINESIS IS CALLED ___________

SOMATIC CELLS

ALL THE CELLS IN YOUR BODY EXCEPT REPRODUCTIVE CELLS (GAMETES)

INTERPHASE

THE CELL PREPARES FOR DIVISION.

G1

CELL GROWS AND PERFORMS NORMAL FUNCTIONS.

S (SYNTHESIS)

DNA IS COPIED.

G2

CELL CONTINUES GROWING AND PREPARES FOR DIVISION.

MITOSIS

NUCLEUS DIVIDES

MITOSIS

THE COPIED CHROMOSOMES ARE SEPARATED INTO TWO NUCLEI

PROPHASE

CHROMOSOMES CONDENSE; SPINDLE FORMS.

METAPHASE

CHROMOSOMES LINE UP IN THE MIDDLE.

ANAPHASE

SISTER CHROMATIDS SEPARATE.

TELOPHASE

TWO NEW NUCLEI FORM.

CYTOKINESIS

CELL SPLITS

CYTOKINESIS

THE CYTOPLASM DIVIDES, PRODUCING TWO SEPARATE DAUGHTER CELLS.

ANIMAL CELL

MEMBRANE PINCHES INWARD.

PLANT CELL

CELL PLATE FORMS.

INTERPHASE

PREPARE THE CELLS

MITOSIS

DIVIDE THE NUCLEUS