Cells and Heredity Chapter 3.1

3.1 Vocabulary Cell membrane – The outer boundary of the cytoplasm, a layer that controls what enters or leaves the cell. Nucleus – The structure in a eukaryotic cell that contains the genetic material a cell needs to reproduce and function. Cycle – a series of events or actions that repeat themselves regularly

3.1 Vocabulary DNA (p74) – The genetic material found in all living cells that contains the information needed for an organism to grow, maintain itself, and reproduce. Chromosome (p75) – The physical structure in a cell that contains the cell’s genetic material

Cell Division 1. Unicellular (Procaryotic cells, no nucleus with enclosed membrane)- reproduce through binary fission.

Cell Division Eukaryotic Cell (multicellular with a nucleus with an enclosed membrane)- Mitosis cell division is involved in growth, development, and repair, as well as in reproduction.

Chromosomes DNA is wrapped around proteins like thread around a spool and compacted into structures. Before division, the chromosomes compact more and become more invisible under a light microscope. During division, a duplicated chromosome can be seen as two identical structures called chromatids that are held together by centromeres.

Genetic material of eukaryotic cells is organized in chromosomes DNA- deoxyribonucleic acid- is a chemical that contains information for an organism’s growth and functions.

DNA Made up of two strands of molecules. Made up of subunits called nucleotides. The genetic material that contains information for a cell’s growth and function

3.1 Notes Cell division is involved in many functions. Cell division occurs in all organisms. You grow because your cells divide and produce more cells All new cells are produced from other cells.

Cell Division is involved in growth and repair Only occurs in multicellular organisms. Growth Development Repair

Bell Work 9/10/09 What is DNA? Where is the DNA located in a Eukaryotic cell? Where is the DNA located in a Prokaryotic cell?

Investigate Chromosomes Pg. 76 in book What did you observe about the loosely balled yarn? What does the loosely balled yarn represent? What does the yarn on the craft sticks represent? Why does the yarn on the craft sticks take up less space than the ball of yarn? How does the yarn’s being wrapped on the craft sticks make it easier to separate the different colors?