MITOSIS

Question 1

AT WHICH PHASE IN THE CELL CYCLE DOES THE CELL MAKE COPIES OF THE DNA?

Answer 1

DURING THE S PHASE (SYNTHESIS PHASE) OF THE INTERPHASE

DNA GETS COPIED DURING THE INTERPHASE OF THE CELL CYCLE, SPECIFICALLY IT HAPPENS DURING THE S PHASE.

DO NOT GET “DNA DUPLICATION” CONFUSED WITH “CELL DIVISION”

CELL DIVISION HAPPENS DURING THE MITIOTIC PHASE OF THE CELL CYCLE

Question 2

WHAT IS A TRUE STATEMENT?

Answer 2

-AT THE END OF THE TELOPHASE II IN MEIOSIS, THERE ARE 4 HAPLOID GAMETE CELLS

-THERE ARE 2 ROUNDS OF MEIOSIS IN THE PROCESS OF MAKIING GAMETE (SEX CELLS)

Question 3

TRUE OR FALSE?

THE CELL CYCLE IS BROKEN DOWN INTO 2 MAJOR PHASES:
INTERPHASE & MITOTIC PHASE

Answer 3

TRUE.

THE MOST EVENTFUL THING RELATED TO INTERPHASE IS DNA DUPLICATION + THE MOST EVENTFUL THING RELATED TO THE MITOTIC PHASE IS CELLULAR DIVISION.

Question 4

WHAT BEST REPRESENTS THE INTERPHASE OF THE CELL CYCLE?

Answer 4

INTERPHASE IS THE LONGEST PHASE OF CELL DIVISION HERE THE CELLS PERFORM THEIR NORMAL FUNCTIONS, GROW + PREPARE FOR CELL DIVISION BY MAKING A COPY OF THEIR ORGANELLES + CHROMOSOMES

*INTERPHASE IS THE LONGEST PART OF THE CELL CYCLE, CELLS SPEND MOST OF THEIR LIFE SPAN IN INTERPHASE. THE MOST EVENTFUL THING THAT YOU NEED TO REMEMBER ABOUT INTERPHASE IS DNA REPLICATION HAPPENS HERE!

Question 5

MITOSIS IS DIVIDED INTO 4?

Answer 5

PROPHASE
INTERPHASE
ANOPHASE
TELOPHASE

Question 6

A DIPLOID CELL HAS 2 SETS OF CHROMOSOMES WITH A TOTAL OF 46 CHROMOSOMES

Answer 6

TRUE

• WHAT WE REFER TO A “DIPLOID” CELL IS A CELL THAT HAS FULLY PAIRED CHROMOSOMES CONSISTING OF ONE MATERNAL + ONE PATERNAL CHROMOSOMES

Question 7

TRUE OR FALSE ?
A HAPLOID CELL HAS 1 SET OF CHROMOSOMES CONSISTING OF ONE MATERNAL + ONE PATERNAL CHROMOSOME

Answer 7

TRUE.

WHAT WE REFER TO AS A “HAPLOID CELL.” IS A CELL THAT HAS ONLY HALF OF THE FULL PAIR. SO IT EITHER HAS THE CHROMOSOME FROM MOM + DAD (FROM ONE HOMOLOGOUS PAIR) BUT NOT BOTH.

Question 8

WHAT BEST DESCRIBES CYTOKINESIS?

Answer 8

CYTOKINESIS IS THE PROCESS OF ONE PARENT CELL SPLITTING INTO TWO DAUGHTER CELLS.

CYTOKINESIS BEGINS DURING TELOPHASE, IT BEGINS WITH A “CLEAVAGE FURROW” FPR,OMG BETWEEN THE TWO DAUGHTER CELLS (SPECIFICALLY AT THE METAPHASE). EVENTUALLY THE TWO DAUGHTER CELL WILL BE “PINCHED” UTIL THEY ARE SEPARATED FROM EACH OTHER.

Question 9

AT WHICH PHASE OF THE CELL CYCLE DO THE CHROMOSOMES LINE UP ON THE METAPHASE PLATE?

Answer 9

METAPHASE
CHROMOSOMES LINE UP DURING METAPHASE

Question 10

WHICH OF THE FOLLOWING DESCRIBE THE PROTEIN STRUCTURE FOUND IN THE CENTROMERE, THAT CONNECTS TO THE MICROTUBLES + ASSISTS IN PULLIG NTHE CHROMOSOMES PART?

Answer 10

KINETOCHORE.

KINECHORE IS THE PROTEIN STRUCTURE THAT IS FOUND INSIDE THE CENTROMERE OF EACH CHROMOSOME. THE KIETOCHORE ACTS KINDA LIKE A BUNGIE CORD THAT ATTACHES TO BOTH THE CHROMOSOME + THE MICROTUBLE.

KINETOCHORE FIBERS ARE ABLE TO PULL THE CHROMOSOME APART DURING ANAPHASE BY CONTRACTING + SHORTENING AS A RESULT OF DEPOLYMERIZATION.

Question 11

WHAT FACTORS WILL STIMULATE GROWTH ARREST?

Answer 11

• CROWDING AROUND A CELL
• OXIDATIVE STRESS ON THE CELL IS NATURALLY AGING OUT
• INFECTION
• LOW LEVELS OF NUTRIENTS/ AND/OR GROWTH FACTORS.
• IF AT ANY POINT A CELL DOES NOT PASS THE CHECKPOINTS DURING THE CELL CYCLE IT WILL BE PUT ON A GROWTH ARREST.

CROWDING AROUND THE CELL , OXIDATIVE STRESS + LOW LEVELS OF NUTRIENTS/ AND OR GROWTH FACTORS WILL STIMULATE GROWTH ARREST.

IF A CELL IS ABLE TO RECOVER IT CAN LEAVE GROWTH ARREST + ENTER BACK INTO THE CELL CYCLE HOWEVER, IF NOT ABLE TO RECOVER + TOO DAMAGED IS WILL PERMANENTLY STAY IN GROWTH ARREST (SENESCENCE)

Question 12

WHAT DESCRIBES THE SENESCENCE STATE?

Answer 12

THESE CELLS PERMANENTLY DO NOT EVER ENTER THE CELL CYCLE, INSTEAD THEY PERMANENTLY EXIST IN GO.

• ALL CELLS EXIST IN CERTAIN “STATES.” IF THE CELL IS NOT ACTIVELY IN THE CELL CYCLE THEN, IT IS N OT IN ONE OF THESE STATES.

QUIESCENT STATE = THESE CELLS STAY DORMANT UNTIL STIMULATED

EX: MATURE LIVER CELLS

SENESCENSE STATE= THESE CELLS ARE NORMALLY DAMAGED + ARE NOT ABLE TO ENTER THE CELL CYCLE

THEY PERMANENTLY STATY IN GO. THESE CELLS NEVR GROW OR DIVIDE

Question 13

WHICH OF THE FOLLOWING DESCRIBE THE APOPTIS?

Answer 13

THE CELL IS PREPROGRAMMED TO DIE AFTER IT HAS COMPLETED ITS JOB.

• SOME CELLS HAVE A “PROGRAMMED DEATH”, ONCE THEY HAVE COMPLETED THEIR JOB THEY DIE OFF.

Question 14

WHAT IS THE FUNCTION OF A CENTROMERE?

Answer 14

CONNECTS 2 CHROMATIDS TOGETHER (MAKING ONE CHROMOSOME)

• THE CENTROMERE IS FOUND IN THE CENTER OF A CHROMOSOME. IT CONNECTS BOTH CHROMATIDS TOGETHER + IS ALSO WHERE THE KINETOCHORE IS FOUND