Biology Cell Structure & Function Quiz Notes

What is the Cell Theory?

1. All living organisms are made up of one or more cells
2. Cells are the basic unit of life
3. All cells come from pre-existing cells

What is a prokaryotic cell?

- Includes bacteria, blue-green algae (Monera).
- Single Cell organisms that lack both a true nucleus and other membrane bounded substructures.
- Prokaryotic DNA is typically circular.

The Fluid Mosaic Model

- Membrane has properties of solids and liquids.
- Forms a "fluid sea" where proteins and lipids etc. form a thin membrane around the cell
Fluid part - contains phospholipids forming phospholipid bilayer.
Solid part - proteins

Nuclear Envelopes

Double membrane (2 Phospholipid Bilayer) that is a continuation of ER

Chromatin

Combination of DNA and Histone Proteins

Chromosomes

Packages DNA during nuclear division, controls gene expression

Nucleolus

Found inside the nucleus and produces ribosomes

What are our knowledge of cells built on?

Work done with microscopes

What is an eukaryotic cell?

- Plants, animals, protozoa, fungi
- Contains nucleus and membrane bound organelles
- Genetic Material organized into chromosomes

Eukaryotic Cell Structure

1. Cell membrane: thin layer containing cell contents. - Plant cells also have a cell wall surrounding the membrane
2. Nucleus: specialized structure within cell containing DNA. Controls cell function and reproduction

Cell Membrane

A cell structure that controls which substances can enter or leave the cell (Transportation). Homeostasis, recognition, communication.

Selectively permeable (allows some substances but not others)

Plant Cells - Cell Wall

- Surrounds cell membrane
- Made up of cellulose fibers
- Selectively permeable

Nucleus

- Control center of the cell
- Determines metabolism, growth, differentiation, structure, reproduction

Nuclear Pores

holes in the nuclear envelope that allow materials to pass in and out of the nucleus

Endoplasmic Reticulum

Increases Surface Area where reactions occur. Channels = storage.

Protein leaving ER goes into Golgi for further processing

Ribosomes = Rough, No ribosomes = Smooth

Ribosomes

Protein Synthesis

Golgi Body

"Quality control", Modifies, Processes and Packages proteins made by the cell that are later packaged into vesicles.

Looks like a flattened stack of hollow tubes.

Like FedEx

Vacuole & Vesicles

Storage depots.

PEETS
P - Pinching off from Golgi
E - Endocytosis of the cell membrane
E - Extension of the ER membrane
T- Transport and storage of materials

Vacuoles in Plants

Plant cells usually have one large central vacuole that stores water, food, waste, cell support and help plants photosynthesize.

Lysosomes

Cellular stomachs - special vesicles animals cells only (sometimes plants) formed by the golgi apparatus.

- Hydrolytic enzymes functioning in:
digestion, disposal, breakdown

Mitochondria

Powerhouse of the cell.

2 membranes, inner and outer.
Inner - cristine
Outer - matrix

Function: AEROBIC ENERGY METABOLISM

Chloroplast

Double-membrane bound structures containing pigments found in plant and algae cells where photosynthesis occurs. Makes food.

Most prominent plastid.

Grana

Looks like pancakes, chlorophyll is located inside.

Chlorophyll is needed to photosynthesize.

Thylakoid

Each pancake (within the stack) is called a thylakoid

Centrioles

Cell organelle that aids in cell division in animal cells (and plant).

Two cylindrical bodies.

The Cytoskeleton

A network of fibers that holds the cell together, helps the cell to keep its shape, and aids in movement

Microtubules

Within Cytoskeleton, hollow, cylindrical aggregates of tubelike structures that help give cell shape and form.

Microfilaments

Long, thin fibers that function in the movement and support of the cell

Formula for Cellular Respiration

C6H12O6 + 6 O2 -> 6CO2 + 6H20 + ENERGY (ATP)

Formula for Photosynthesis

6CO2 + 6H2O → C6H12O6 + 6O2