Notes: Life of a Cell

Part 1: Understanding the Chromosome

I. Understanding DNA as a Chromosome5 Key Points

A. Found in the

NUCLEUS of the cell

I. Understanding DNA as a Chromosome5 Key Points

B. Composed of 1 very large, compacted,

TIGHTLY COILED strand of DNA

1. DNA name: DEOXYRIBOSE NUCLEIC ACID• Contains the HEREDITARY INFORMATION

for the assembly of PROTEINS in the body that specifies cell structure and function

I. Understanding DNA as a Chromosome5 Key Points

2. Built by repeating subunits or monomers

called NUCLEOTIDES: 3 parts

a. DEOXYRIBOSE SUGAR

b. PHOSPHATE GROUP

c. NITROGEN BASES (A,T,C,G)

I. Understanding DNA as a Chromosome5 Key Points

NitrogenDraw this and label it!

DNA Nucleotide

I. Understanding DNA as a Chromosome5 Key Points

3. GENE: a segment of DNA coding for a specific trait

I. Understanding DNA as a Chromosome5 Key Points

C. Chromosome appearance in the cell varies

1. LOOSELY coiled: dark mass

2. TIGHTLY coiled: extended threadlike strands Can be seen during stages

of cell division

I. Understanding DNA as a Chromosome5 Key Points

D. Chromosome number - Humans

Chromosome # in Humans

HAPLOID = 23 Chromosomes-1/2 set of chromosomes-Gamete: sex cells-ex: sperm and egg

Diploid = 46 Chromosomes-Full set of chromosomes-Somatic Cell: body cellsEx: skin, liver, zygote

HAPLOID = 23 Chromosomes-1/2 set of chromosomes-Gamete: sex cells-ex: sperm and egg

I. Understanding DNA as a Chromosome5 Key Points

D. Chromosome number - Humans

Chromosome # in Humans

HAPLOID = 23 Chromosomes-1/2 set of chromosomes-Gamete: sex cells-ex: sperm and egg

Diploid = 46 Chromosomes-Full set of chromosomes-Somatic Cell: body cellsEx: skin, liver, zygote

Diploid = 46 Chromosomes-Full set of chromosomes-Somatic Cell: body cellsEx: skin, liver, zygote

I. Understanding DNA as a Chromosome5 Key Points

E. Chromosomes have the ability to

REPLICATE or COPY ITSELF Once DNA copies itself, it will contain an

identical half