CELLSMolecular Biology Techniques

WHICH TYPE OF CELL HAS A NUCLEUS?

1 2

50%50%1. Prokaryotic2. Eukaryotic

EUKARYOTIC VERSUS PROKARYOTIC CELLS

Prokaryotic - Cells lacking a nucleus. Eukrayotic - Cells containing a nucleus.

Organelles - Membrane-bound bodies found within eukaryotic cells.

CELL STRUCTURE

Cell wall: Rigid boundaries of the cellCellulose: organic compound that makes up

the majority of plant cell walls Cotton is 90% cellulose

Hemicellulose: Gluelike substance that holds cellulose fibers together within the wall

Pectin: Organic matter that provides stiffness

CELL STRUCTURE Cell (Plasma) Membrane: Binds all the living components within the protoplasm

Cytoplasm: All cellular components between the plasma membrane and the nucleus

WHAT IS THE NAME OF THE JELLY LIKE SUBSTANCE WHERE MANY CHEMICAL REACTIONS TAKE PLACE AND CELL ORGANELLES ARE EMBEDDED?

1 2 3 4

25% 25%25%25%

1. Cytoplasm2. Chloroplast3. Nucleus4. Cellulose

NUCLEUS Nucleus: Control center of the cell, houses DNA, DNA

provides information needed to fulfill the cells’ needs (growth, differentiation, etc) & stores heredity information Nuclear Envelope: Structurally complex pores,

proteins that act as channels for molecules are within the pores, acts as gatekeeper between nucleus and rest of cell

Chromatin: Composed of proteins and DNA, when nucleus divides for mitosis, chromatin coils.

Chromosomes: Condensed condition of chromatin. Each plant/animal cell has its own fixed number of chromosomes, radish has 18, humans have 46.

WHAT CONTROLS REPRODUCTION AND CONTAINS THE GENETIC INFO OF THE CELL?

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25% 25%25%25%1. Cell wall2. Nucleus3. Nuclear

envelope4. Plastids

ENDOPLASMIC RETICULUM (ER) Endoplasmic Reticulum facilitates cellular

communication and materials channeling. Connected to outer membrane of nucleus Rough ER distributes ribosomes Smooth ER associated with lipid secretion

RIBOSOMES

Ribosomes are composed of two subunits composed of RNA and proteins. involved in linking amino acids for the

construction of large protein molecules

GOLGI APPARATUS are often bound

by branching tubules that originate from the ER. Involved in the

modification of carbohydrates attached to proteins synthesized and packaged in the ER.

PLASTIDS Plastids: associated with the storage or manufacturing

of carbohydratesChloroplasts: Location of photosynthesis, contain

stacks of grana Grana/Granum: contain thylakoids Thylakoids: contain chlorophyll Chlorophyll: give green pigment

Chromoplasts Found in colored plant organs, like fruits & petals. Some chloroplasts evolve into chromoplasts (like ripening

tomatoes). Leucoplasts

No pigment, assumed to be in roots. May become specialized for bulk storage of starch, lipid or

protein.

WHAT IS THE LOCATION OF PHOTOSYNTHESIS IN THE CELL?

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25% 25%25%25%1. Plastids2. Chloroplast3. Chromoplasts4. Leucoplasts

WHAT GIVES PLANTS THEIR GREEN PIGMENT?

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25% 25%25%25%1. Grana2. Thylakoids3. Dictyosomes4. Chlorophyll

MITOCHONDRIA

Mitochondria release energy produced from cellular respiration. Powerhouse of the cell

H2O

Glycolysis

Krebs Cycle

Electron Transport Chain

VACUOLES

Used for storage in plants In mature cells, 90% of

volume may be taken up by central vacuoles bounded by vacuolar membranes.

Filled with cell sap which helps maintain pressure within the cell.

Also frequently contains water-soluble pigments, like anthocynanin which provide color for flowers.

CYTOSKELETON Cytoskeleton is an

intricate network of microtubules and microfilaments. Microtubules control

the addition of cellulose to the cell wall.

SUMMARY Cytoplasm Jelly like substance where chemical reactions

take place and other parts are embedded. Nucleus Controls reproduction and also contains the

characteristics of the cell. Cell membrane Surrounds the cell and controls what

moves in and out of the cell. Mitochondria Found only in plant cells where respiration

occurs. Chloroplasts These makes plants green. They contain

chlorophyll which is needed for photosynthesis.

WHAT GIVES CELLS THEIR SHAPE?

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25% 25%25%25%1. Cell wall2. Cell membrane3. Sap4. Vacuoles

SUMMARY Cell wall Gives the cell its shape. The cell's "skeleton". Vacuole Where the cell sap is stored, controls pressure Golgi Apparatus Involved in the modification of

carbohydrates attached to proteins synthesized Endoplasmic Reticulum Facilitates cellular

communication and materials channeling, distributes ribosomes

Ribosomes Involved in protein synthesis

CELLULAR REPRODUCTION

Cell division process referred to as cell cycle. Divided into interphase and mitosis.

Interphase Period when cells are not dividing.

G1 - Cell increases in size. S - DNA replication takes place. G2- Mitochondria divide, and microtubules produced.

http://www.youtube.com/watch?v=O3_PNiLWBjY

MITOSIS

Mitosis refers to the process of cellular division that produces two daughter cells with equal amounts of DNA and other substances duplicated during interphase. Each daughter cell is an exact copy of the parent

cell. Mitosis occurs in meristems.

PROPHASE

Chromosomes condense. Strands of chromatin coil and tighten with

centromeres holding each pair of chromatids together.

Nuclear envelope fragments.

METAPHASE

Chromosomes align at the cell’s equator. Spindle fibers collectively referred to as the

spindle. At the end of metaphase, the centromeres

holding each sister chromosomes separate lengthwise.

ANAPHASE

Sister chromatids separate and are pulled to opposite poles. Spindle fibers gradually shorten as material is

continuously removed from the polar ends.

TELOPHASE

Each group of daughter chromosomes become surrounded by a nuclear envelope.

Daughter chromosomes become indistinguishable. Nucleoli reappear Spindle fibers disintegrate Cell plate forms.

MITOSIS IN ACTION

http://www.youtube.com/watch?v=VlN7K1-9QB0&feature=related

http://www.youtube.com/watch?annotation_id=annotation_706798&v=VGV3fv-uZYI&feature=iv