Bio Test Cell Theory and Division

Cell Theory

All living things must be made up of cells

Prokaryote

Found in bacteria

Cell Theory

All living things must be made up of cells

Prokaryote

Found in bacteria

single, circular DNA

no nucleus

simple, small

no membrane bound organelles

Eukaryote Cell

Multi or single celled

Has nucleus

DNA in multiple chromosomes

large, more complex

membrane bound organelles

Both Eukaryote and Prokaryote

Cell membrane

DNA

Have ribosomes

Endosymbiont Theory

Chloroplasts and Mitochondria were once prokaryotic cells

Evidence of Endosymbiont Theory

Have their own ribosomes

Have their own DNA

Surrounded by different membranes

Nucleus

Contains the genetic material in the Cell and directs cell activites

Rough ER

Makes proteins, folds them and puts them into vesicles

Ribosome

Makes proteins

Golgi Apparatus

Modifies and finishes proteins and puts them into vesicles to secrete and become lysomes

Lysosome

Contains enzymes and breaks down old/used parts of the cell

Mitochondria

Breaks down sugar and puts energy into ATP

Chloroplast

Traps light energy and puts it into sugars

Cytoplasm

A liquid substance that fills cells and surrounds organelles

Cytoskeleton

Provides structure to cells, involved in motion

Nucleolus

Is where ribosomes are made

Vacuole

A membrane bound sac used for storage

Cell Wall

Provides support for plant cells

Cell Membrane

Surrounds cells and controls movements of substances into and out of the cell

Vesticle

Moves proteins from the Rough ER to Golgi and from the Golgi to the cell membrane

Smooth ER

Makes lipids and carbohydrates

Hypertonic

Water leaves the cell, the cell shrinks

Hypotonic

Water enters the cell, cell swells and bursts

Isotonic

Water moves in both directions, in and out of the cell

Longest Phase in the Cell Cycle

Interphase

Two main stages of the cell cycle

Mitosis and interphase

Cells work efficiently in a

large surface area

G1

Growth phase: cells increase in size, makes proteins and organelles

S

Synthesis Phase: DNA is copied

G2

Preparation for Division

Prophase

chromosomes become visible, centrioles and spindles appear

Nuclear membrane breaks down

Metaphase

Chromosomes line up in the middle of the cell

Anaphase

Sister chromatids are pulled apart

Cytokinesis

Chromosomes unwind, 2 new nuclei

Mitosis

The division of nucleus

Cytokinesis

Division of cytoplasm

Cytokinesis in Plant Cells

Cell plate forms to divide cell

Cytokinesis in Animal Cells

Cell membrane forms to divide cell

What is apoptosis?

Planned Cell death, gets rid of old or damaged cells and replaces them with new ones

What is cancer?

Uncontrolled cell division

Differentiation

Cells continue to change to become specialized to do a specific job

homologous structures

2 chromosomes in regular 2N cells that are the same size, shape, and carry genes for the same traits

Tetrad

Structure when homologous chromosomes come close together in Prophase I

Crossing over

When homologous chromosomes exchange pieces of DNA

Purpose of Mitosis

Growth, repair, asexual reproduction

Purpose of Meiosis

Formation of IN gametes for sexual reproduction

Where does mitosis occur

Body cells

where does meiosis occur

Ovaries/Testicles

Result of Mitosis

Two diploid cells

Result of Meiosis

Four haploid cells

Human diploid number

46

Prophase I

Tetrads form and crossing over occurs

Anaphase II

Chromatids separate

Metaphase I

Homologous chromosomes line up in the middle

Anaphase II

Chromosomes separate

telaphase II

New nuclei form in four 1N cells

Fertilization

Joining of egg and sperm

What effect does fertilzation have on the number of chromosomes resulting zygote cell

Fertilization restores the normal number of chromosomes

How do meiosis and fertilzaiton work together?

Maintain constant diploid number of chromosomes from one generation to another