1. Cells and Their Functions Part 1
Chapter 3
Cells and Their Functions
Part 1

2. The Role of Cells Cytology is the study of cells
Basic unit of all life
Have all characteristics of life
Organization
Metabolism
Responsiveness
Homeostasis
Growth
Reproduction
Can live independently of other cells

3. Cell Structure All animal cells share the following structures:
Plasma Membrane
Nucleus
Nucleolus
Cytoplasm
Endoplasmic Reticulum
Ribosomes
Mitochondria
Golgi Apparatus
Lysosomes
Peroxisomes
Vesicles
Centrioles
Cilia
Flagellum

5. Encloses cell contents Participates in cellular activities
Plasma Membrane
Encloses cell contents
Participates in cellular
activities
Bilayer structure
Phospholipids
Cholesterol
Carbohydrates
Proteins – a variety of functions

6. Check for understanding

7. Largest organelle in a cell Chromosomes Nucleolus
The Nucleus
Largest organelle in a cell
Chromosomes
Nucleolus
The Cytoplasm
Material that fills the cell from the nuclear membrane to the plasma membrane
Contains most of the cell’s organelles

8. Organelles Endoplasmic Reticulum Ribosomes (in ER or cytoplasm)
Network of membranes between nuclear membrane and plasma membrane
Rough (with ribosomes)
Sorts proteins and makes simple into complex
Smooth
Makes fats/lipids
Ribosomes (in ER or cytoplasm)
Makes Proteins
Mitochondria (large folded membranes)
Energy to run the cell ---ATP

9. Golgi Apparatus(stack of membranous sacs)
Sort and modify proteins and package for export from cell
Lysosomes
Digestive enzymes that remove waste and foreign material (old cells, break down nutrients)
Peroxisomes
Enzymes to destroy harmful substances produced in metabolism, also drugs and alcohol
Vesicles
Bubbles for storage and move things in/out of cell
Centrioles
Function in cell division by organizing the cell

10. Structures projecting from the cell surface used for motion Cilia
Surface Organelles
Structures projecting from the cell surface used for motion
Cilia
Flagellum
Microvilli

11. Individual cells vary widely Size Shape Function
Cellular Diversity
Individual cells vary widely
Size
Shape
Function

12. Check for understanding

13. Cell Function Cells have two basic functions: Protein Synthesis
Transcription
Translation
Cell Division
DNA Replication

14. Protein Synthesis
The cell’s genetic material contains the information needed to make proteins
DNA and RNA (Nucleic Acids) have similar structures
Four nucleotides
Adenine (A)
Guanine (G)
Cytosine (C)
Thymine (T) in DNA or uracil (U) in RNA
Sugar
Deoxyribose in DNA or ribose in RNA
Phosphate
Nitrogen base

15. DNA in a cell occurs mainly in chromosomes
Genes are subdivisions of chromosome
Genes code for the building of amino acids
Amino acids form together to create proteins

16. Chromosomes—Genes---------DNA Segment---------Nucleotide

17. DNA vs. RNA Location: nucleus
Composition: Nucleotides: Adenine, Guanine, cytosine, or thymine
Structure: Double Stranded helix by nucleotide pairing A-T;G-C
Makes up chromosomes, hereditary units that control all cell activities; divided into genes that carry nucleotide codes to make proteins
Cytoplasm
Nucleotides: Adenine, Guanine, Cytosine and Uracil
Single Strand
Manufacture proteins according to codes carried in DNA; three types messenger RNA (mRNA), ribosomal RNA (rRNA), transfer RNA (tRNA)

18. Check for understanding

19. The Role of RNA Protein synthesis
Transcription – copying the genetic code in the nucleus and taking those instructions to the endoplasmic reticulum
Messenger RNA (mRNA)
Transcription video
Translation – taking the instructions from the mRNA and creating amino acids, as well linking them together to create proteins
Transfer RNA (tRNA)
Ribosomal RNA (rRNA)
Translation Video

20. Transcription. animation

21. RNA Types
Messenger RNA (mRNA)-built on a strand of DNA and takes the message to the cytoplasm and attaches to a ribosome.
Ribosomal RNA (rRNA)- makes up ribosome, where protein synthesis happens and helps translate the message
Transfer RNA (tRNA)-works with other forms of RNA to translate the genetic code into protein; each molecule of tRNA carries an amino acid that can build a protein at the ribosome

22. Translation. animation

23. Check for understanding