BIOL Laboratory Final Exam

What is the Cell Theory?

1. All cells come from other cells

2. All organisms are composed of one or more cells

3. The cell is the smallest unit that possesses the characteristics of life

What are the 3 main components of a Nucleotide?

1. 5 Carbon sugar Pyrimidines- Cytosine, Uracil, Thymine

2. Phosphate group Purines- Adenine, Guanine

3. Nitrogenous base (RNA contains Uracil instead of Thymine) (A-T, C-G)

DNA Replication

Enables DNA molecule to copy itself during mitosis (cell division)

What are the functions of DNA?

DNA stores instructions in the form of genes for traits or characters that enables an organism to develop, survive and reproduce.

Proteins

• Do most of the work in cells of an organism

• Required for structure, function and regulation

Nucleus

An organelle found in the cells of eukaryotic organisms, location of DNA

Chromosomes

Tightly packed DNA

Genome

An organism's complete set of nuclear DNA

Mitochondria

Have a small amount of DNA

Central Dogma of Gene Expression

DNA - Transcription - mRNA - Translation - Protein

The Cell Cycle

Lasts from the beginning of one cell division until the beginning of the next.

It includes the time when cells are dividing (mitosis) and the time when cells are not dividing (interphase)

Interphase

Cells are carrying out their normal everyday functions unrelated to cell division

G₁ Phase

The cell grows and functions normally

S Phase

The cell replicates its DNA, copying its entire genome—every chromosome

G₂ Phase

The cell produces organelles & other molecules that are needed for the two daughter cells

Mitosis

Generates exact cell copies

The division of the nucleus

PMAT

Cytokinesis

The division of the cell itself into 2 new cells

In animals, the cell will pinch off the cell membrane so that it forms a cleavage furrow

In plants a cell plate forms

Prophase

Chromosomes condense, spindle fibers grow from centrioles, nucleus breaks down & spindle fibers attach to centromere on chromosomes

Metaphase

Centrioles using spindle fibers will line up the sister chromatids along the equator (metaphase plate) of the cell

Anaphase

Sister chromatids are pulled apart by spindle fibers to opposite sides of the cell & cell stretches

Telophase

Chromosomes begin to unwind, the nucleus reforms

Trait

Alternative forms are known as alleles, found at same place on a chromosome

Homozygous

Alleles are the same

Heterozygous

Alleles are different 

Principle of Segregation

The two alleles for a gene segregate (separate) during gamete formation (meiosis) and are rejoined at random, one from each parent, during fertilization

Punnet Square

Is often used to work and predict the outcome of a monohybrid cross

Principle of Dominance

In a cross of parents that are pure (homozygous) for different traits, only one phenotype of the trait will appear in the next generation. Offspring that have a hybrid genotype will only exhibit the dominant trait.

Principle of Independent Assortment

Inheritance of one trait, seed color has no effect on the inheritance of another trait, seed shape. The possible assortments can be determined by completing a dihybrid cross.

What are Mendel’s 3 Principle’s

Principle of Dominance

Principle of Segregation

Principle of Independent Assortment

Incomplete Dominance

Partial expression of an allele resulting in an intermediate phenotype

Codominance

Both alleles are expressed. Ia & Ib result in AB blood type

Pleiotrophy

One gene influences multiple traits, sickle-cell disease. (ss have disease, Ss usually healthy but sometimes partially affected, SS not affected)

Polygenetic inheritance

Additive effects of two or more genes on a single phenotypic trait.