Presentation is loading. Please wait.

Presentation is loading. Please wait.

CELL GROWTH & DIVISION Image by Riedell. CELL GROWTH & DIVISION Image by Riedell.

Similar presentations


Presentation on theme: "CELL GROWTH & DIVISION Image by Riedell. CELL GROWTH & DIVISION Image by Riedell."— Presentation transcript:

1

2 CELL GROWTH & DIVISION Image by Riedell

3 2 Reasons why cells divide
DNA OVERLOAD 1. _____________________ As cells grow bigger demand on DNA “genetic library” becomes too great Ex: Small town library has 1000 books. As town grows and more people borrow books, there may be a waiting list to read the most popular titles

4 2 Reasons why cells divide
Material exchange can’t keep up 2. _____________________ As cell grows bigger demand for transport across membrane is too great

5 Ability to transport of oxygen, food, waste across cell membrane depends on _______________
SURFACE AREA

6 BIGGER CELLS NEED MORE FOOD and OXYGEN, but CAN’T TRANSPORT
IT FAST ENOUGH or IN BIG ENOUGH QUANTITIES!

7 mainly by increasing cell number
Image from: Image by Riedell Multicellular organisms grow mainly by increasing cell number

8 DNA CAN BE: SPREAD OUT IN NON-DIVIDING CELLS SCRUNCHED UP
IN DIVIDING CELLS CHROMATIN CHROMOSOMES

9 DNA in PROKARYOTES BACTERIAL DNA is CIRCULAR HAVE ONE CHROMOSOME
NO NUCLEUS; ATTACHED TO CELL MEMBRANE

10 DNA in EUKARYOTES (Plants & Animals)
DNA is ROD-SHAPED CHROMOSOMES MANY PAIRS FOUND IN NUCLEUS

11 Chromosome structure CHROMATIDS CENTROMERE HOMOLOGOUS
Sister_________________ identical arms __________________ constricted area holds chromatids together CENTROMERE HOMOLOGOUS __________________ PAIR 2 of each chromosome (one from mom; one from dad)

12 HOMOLOGOUS CHROMOSOMES
SAME SIZE SAME SHAPE CARRY GENES for the SAME TRAITS BUT ______________! (Don’t have to have the SAME CHOICES) NOT IDENTICAL

13 Vocabulary to Know: Karotypes- “chromosomes map” used to ID potential problems.

14 Vocabulary to Know: Somatic cell- any cell in the body except egg and sperm Diploid- contain two sets of chromosomes Human diploid number- 46 total chromosomes which is equal to 23 pairs of chromosomes Haploid- egg and sperm, half the genetic information Spindle- collection of fibers made of microtubules involved in cell division (aid in stretching the cell apart)

15 CELL DIVISION in PROKARYOTES
Bacteria reproduce using __________________________________ BINARY FISSION

16 Cell Cycle Concept Map Cell Cycle includes is divided into

17 Cell Cycle Concept Map Cell Cycle includes M phase (Mitosis)
Interphase is divided into is divided into G1 phase S phase Prophase G2 phase Metaphase Telophase Anaphase

18

19 ÷ Cells STOP dividing Ex: nerve cell Copy DNA
NOT dividing G1 S G2 Copy DNA Growth Cell makes molecules & organelles needed by new cell DNA = chromatin Growth Cell is “doing its job” DNA=chromatin Cells spend most of life here ÷ Dividing (DNA=chromosomes)

20 Can’t see chromosomes DNA is spread out as chromatin
INTERPHASE (IN BETWEEN DIVIDING) DNA is spread out as chromatin Nuclear membrane is visible Nucleolus is visible DNA is copied during S phase Can’t see chromosomes DNA gets copied (S) Cell gets ready to divide

21 PROPHASE Chromatin scrunches into chromosomes
Pearson Education Inc publishing as Pearson Prentice Hall PROPHASE 1st dividing phase Chromatin scrunches into chromosomes Centrioles appear & move to poles Nuclear membrane & nucleolus disappear Spindle fibers appear

22 METAPHASE (MIDDLE) Chromosomes line up in ___________ middle
Images from: Pearson Eduction Ince; Publishing as Pearson Prentice Hall

23 ANAPHASE (APART) Centromeres split and pull chromatids to the poles
Images from: Pearson Eduction Ince; Publishing as Pearson Prentice Hall

24 Nuclear membrane & nucleolus return
TELOPHASE (TWO NUCLEI) “REVERSE PROPHASE” Nuclear membrane & nucleolus return Chromosomes spread out as chromatin Centrioles disappear Spindle fibers disappear Images from: Pearson Eduction Ince; Publishing as Pearson Prentice Hall

25 CYTOKINESIS (CYTOPLASM splits)
Cytoplasm splits into 2 cells Cleavage furrow pinches in animal cells CLEAVAGE FURROW

26 CYTOKINESIS Cell Plate forms in plant cells CELL PLATE


Download ppt "CELL GROWTH & DIVISION Image by Riedell. CELL GROWTH & DIVISION Image by Riedell."

Similar presentations


Ads by Google