Student Cells Chapter 2

8/18/2019 Student Cells Chapter 2

1/28

+

Chapter 2

Cells

8/18/2019 Student Cells Chapter 2

2/28

+Introducing Cells…Why Study

Cells?!  Activities within cells produce: inherited traits, behaviors, health

! Understanding cell function results in understanding cell dysfunction

! Somatic cells: aka body cells; have two copies of the genome (diploid)

! Gametes: have one copy of the genome (haploid)

! Stem cells: diploid cells that self-replicate

! Types of cells subdivided into three domains:

!  Archaea: prokaryote; single-celled; lacks nucleus

! Bacteria: prokaryote; single-celled; lacks nucleus

! Eukarya: eukaryote; single and multi-celled; nucleus and organelles present

!  All three contain ribosomes " protein synthesis

8/18/2019 Student Cells Chapter 2

3/28

8/18/2019 Student Cells Chapter 2

4/28

+ Chemical Constituents

8/18/2019 Student Cells Chapter 2

5/28

8/18/2019 Student Cells Chapter 2

6/28

+ My Favorite Protein

Example…Enzymes

8/18/2019 Student Cells Chapter 2

7/28

+Other Functions of Enzymes

! Display specificity

!  Act as a catalyst

!  Are temperature

sensitive

!  Are pH sensitive

!  Are concentration

sensitive

! Can be inhibited

8/18/2019 Student Cells Chapter 2

8/28

+Prokaryote vs Eukaryote

8/18/2019 Student Cells Chapter 2

9/28

8/18/2019 Student Cells Chapter 2

10/28

8/18/2019 Student Cells Chapter 2

11/28

8/18/2019 Student Cells Chapter 2

12/28

8/18/2019 Student Cells Chapter 2

13/28

+Progeria

8/18/2019 Student Cells Chapter 2

14/28

Protein-folding associated

diseases include: Alzheimer’s,

Parkinson’s, ALS, type II diabetes

8/18/2019 Student Cells Chapter 2

15/28

8/18/2019 Student Cells Chapter 2

16/28

8/18/2019 Student Cells Chapter 2

17/28

8/18/2019 Student Cells Chapter 2

18/28

+Membrane Proteins

8/18/2019 Student Cells Chapter 2

19/28

8/18/2019 Student Cells Chapter 2

20/28

8/18/2019 Student Cells Chapter 2

21/28

+Cell Division and Death

! Mitosis: division of nuclear material

! Duplicates chromosomes

! Maintains 23 pairs of chromosomes (in somatic cells)

! Cytokinesis: division of cytoplasmic material

!  Apoptosis: programmed cell death

! Cell cycle: activities of preparation and completion of cell division

! Cycle is continual, but divided into two stages

! Interphase: non-dividing stage

! Mitosis: division stage

8/18/2019 Student Cells Chapter 2

22/28

+Interphase

! G1: synthesis of proteins,

lipids, CHO (needed for new

plasma membranes)

!  Varies the greatest

! S: results in two copies of the

chromosomes joined at the

centromere

! G2: occurs following DNAsynthesis, prior to mitosis

!  Additional proteins made

8/18/2019 Student Cells Chapter 2

23/28

8/18/2019 Student Cells Chapter 2

24/28

8/18/2019 Student Cells Chapter 2

25/28

+How a Cell Knows the # of Divisions

8/18/2019 Student Cells Chapter 2

26/28

8/18/2019 Student Cells Chapter 2

27/28

+ Apoptosis: Programmed Cell

Death! Continual process, initialized by activation of a cell membrane

receptor " activation of caspases

!

Caspases (within the cell) destroy enzymes necessary for DNAreplication/repair

! Tear apart cytoskeleton " nuclear collapse " condensation of DNA 

! Destroy mitochondria

! Flips phosphtidylserine to the external plasma membrane " serves

as an uptake mechanism via macrophages

8/18/2019 Student Cells Chapter 2

28/28

 Anti-apoptotic proteins bind to and

inactivate pro-apoptotic proteins inhealthy cells" no death

Death receptors on cell surfaces

bind to death signaling molecules

" death