The Cell: Anatomy & Division Pg. 30 Goals for Today: 1. Learn the anatomy of cells 2. Learn the function of each cell part 3. Become familiar with Mitosis PRACTICAL 1 IS NEXT WEEK !!!!!!!!!

Homework Pg. 525 #1, 3 Pg. 526 #4 Pg. 527 #8, 9 Pg. 528 #11, 12

What is a Cell? Cells are the structural unit of the body. Form the tissues

The Diversity of Cells Epithelial Cells Red Blood Cells Gametes Skeletal muscle cells Cartilage cells

Cell Anatomy – The Plasma Membrane Separates the cell from outside environment Has selective permeability

Selective Permeability Bouncer lets some people into the bar, but not all people

Cellular Anatomy - Nucleus Control center of the cell Contains the DNA Surrounded by a nuclear membrane

Cell Anatomy - Cytoplasm Contents of cell outside the nucleus Contains the organelles

The Organelles The machinery of the cell Enable cells to perform functions Ex: produce ATP, create proteins Kitchen Cell Organelles Nucleus

Organelles – The Ribosome Location of protein synthesis Found free-floating or attached to endoplasmic reticulum (Rough ER)

Organelles – Rough Endoplasmic Reticulum Rough ER stores and transports proteins made on the ribosomes

Organelles – Smooth Endoplasmic Reticulum Smooth ER creates steroids and lipids

Organelles – The Golgi Apparatus Flattened sacs that package proteins for export out of the cell.

Organelles – Lysosomes Contain digestive enzymes Digest foreign substances entering the cell

Organelles – The Peroxisome Contains the catalase enzyme Controls the accumulation of H2O2 in body

Organelles – Mitochondria Powerhouse of the cell Produces ATP through breakdown of glucose

Cells Need to Reproduce Growth 2. Replace old, worn out cells

The Cell Cycle

Interphase Cell spends most of its time in this phase DNA in long strands called “chromatin” Nuclear envelope intact DNA replication occurs during the S Stage

Mitosis Division of the cell nucleus One cell splits into 2 identical daughter cells 4 stages Prophase Metaphase Anaphase Telophase

Prophase Chromatin shortens into chromosomes Chromosomes made up of 2 threads called “Sister Chromatids” held together at the centromere

(S Phase) Centromere

Prophase Nuclear envelope breaks apart Sister chromatids migrate to center of cell

Metaphase Sister Chromatids line up in center of cell along the “metaphase plate” Mitotic Spindle present

Anaphase Centromere of sister chromatid splits Each chromosome is pulled to opposite end of the cell by the mitotic spindle

Telophase Chromosomal movement stops Chromosomes uncoil into thin chromatin Nuclear envelope reappears Cytokinesis occurs

Cytokinesis Division of the cytoplasm in a cell Cleavage furrow squeezes cells apart Formation of two identical daughter cells Daughter Cell Cleavage Furrow Daughter Cell

Mitosis vs. Meiosis vs. Cytokinesis Mitosis: Division of the NUCLEUS in the cell Meiosis: Nuclear division of gametes (egg,sperm) Cytokinesis: Division of CYTOPLASM at the end of Mitosis

Which stage of Mitosis are these cells in?