Compendium Review # 1

For Chapters 1-4:

--Basic Characteristics of Life
Life has an astounding variety of forms and occupies a diverse range of habitats. Yet all life shares common characteristics. The structure of DNA, the ability to respond to environmental stimuli, and the existence of a finite lifespan are common to all living organisms. The characteristics shared by all living things and how organisms acquire their basic needs from their environment.

Cells are the basic and fundamental units of life

Carbohydrates are made up of simple sugars and its function is Energy.

Protiens are made up of Amino Acids and its functions is Catalyze reactions.

Fats are made up of Amino Acids and its function is the cell membrane.

DNA/RNA are made up of Nucleotides and its function is Information.

--Molecules of Life
All living organism pass information from one generation to the next with genetic material containing the information needed to construct a complete organism. The number of genes vary from organism to organism.The gene is the unit of genetic infomation. More complex organisms require a greater number of genes to perform life functions. A gene does not function autonomously, but relies upon other cellular components for its function.All cellular activities obey the known laws of physics and chemistry.What are genes made of?All genes regardless of the type of organism are made of the same basic building blocks called nucleic acids. These nucleic acids combine to form long strands know as deoxyribonucleic acid (DNA). There are four different types of DNA adenine (A), cytosine (C), thymine (T), Guanine (G)

--Cell Structure & Function

Cell MembraneStructure

- same as unit membrane.

Function

- acts as a boundary layer to contain the cytoplasm (fluid in cell)

- interlocking surfaces bind cells together

- selectively permeable to select chemicals that pass in and out of cells
Cell Wall

Structure
- a non-living secretion of the cell membrane, composed of cellulose
- cellulose fibrils deposited in alternating layers for strength
- contains pits (openings) that make it totally permeableFunction
- provides protection from physical injury
- together with vacuole, provides skeletal support
- a single layer of unit membrane enclosing fluid in a sack

Function
- produces turgor pressure against cell wall for support
- stores water and various chemicals
- may store insoluble wastes

Nucleus
The nucleus consists of the nuclear envelope, nucleolus, chromatin, and nucleoplasm.

Nuclear Envelope
Structure

-two unit membranes with a fluid-filled space

-nuclear pores present

-outer membrane may be continuous with endoplasmic reticulum
Function

-selectively permeable to control movement in or out -contains nuclear contents

Chromatin
Structure

-composed of long thin strands of DNA
Function

-contains instructions that control cell metabolism and heredity

Nucleolus
Structure

-non-membraneous matrix of RNA (ribonucleic acid) and protein
Function

- instructions in DNA are copied here

- works with ribosomes in the synthesis of protein

Chloroplast
Structure

- composed of a double layer of modified membrane (protein, chlorophyll, lipid)

- inner membrane invaginates to form layers called "grana" (sing.,granum) where chlorophyll is concentrated
Function

- site of photosynthesis
chlorophyll Carbon Dioxide + Water --> Glucose +Oxygen radiant energy (food)

Centriole
Structure

- nine triplets of microtubules form one centriole

- two centrioles form one centrosome
Function

- forms spindle fibres to separate chromosomes during cell division

Endoplasmic Reticulum (ER)
Structure

- sheets of unit membrane with ribosomes on the outside

- forms a tubular network throughout the cell

Function

- transports chemicals between cells and within cells

- provides a large surface area for the organization of chemical reactions and synthesis

Ribosome
Structure

- non-membraneous, spherical bodies composed of RNA (ribonucleic acid) and protein enzymes
Function

- site of protein synthesis

Golgi Apparatus
Structure

- stacks of flattened sacs of unit membrane (cisternae)

- vesicles pinch off the edges
Function

- modifies chemicals to make them functional

- secretes chemicals in tiny vesicles

- stores chemicals

- may produce endoplasmic reticulum

Mitochondrion
Structure

- composed of modified double unit membrane (protein, lipid)

- inner membrane infolded to form cristae
Function

- site of cellular respiration ie. the release of chemical energy from food
Glucose + Oxygen --> Carbon Dioxide + Water + Energy (ATP)

Lysosome
Structure

- membrane bound bag containing hydrolytic enzymes

- hydrolytic enzyme = (water split biological catalyst). using water to split chemical bonds
Function

- break large molecules into small molecules by inserting a molecule of water into the chemical bond

--Cell Organelles

Living cells are divided into two types

- procaryotic and eucaryotic

This division is based on internal complexity.

Eucaryotic:

The cells of protozoa, higher plants and animals are highly structured. These cells tend to be larger than the cells of bacteria, and have developed specialized packaging and transport mechanisms that may be necessary to support their larger size.

Procaryotic:

These cells are simple in structure, with no recognizable organelles. They have an outer cell wall that gives them shape. Just under the rigid cell wall is the more fluid cell membrane. The cytoplasm enclosed within the cell membrane does not exhibit much structure when viewed by electron microscopy.

--Various Tissues

There are four major tissue types in the body.

1. Connective-

Connective tissues bind structures together, and form a framework and support for organs and the body as a whole, it store fat, transport substances, protect against disease, and help repair tissue damage. They occur throughout the body. Connective tissues are characterized by an abundance of intercellular matrix with relatively few cells. Connective tissue cells are able to reproduce but not as rapidly as epithelial cells. Most connective tissues have a good blood supply but some do not.
2. Muscular-

Muscle tissue is composed of cells that have the special ability to shorten or contract in order to produce movement of the body parts. The tissue is highly cellular and is well supplied with blood vessels. The cells are long and slender so they are sometimes called muscle fibers, and these are usually arranged in bundles or layers that are surrounded by connective tissue. Actin and myosin are contractile proteins in muscle tissue.

3. Nervous-
Nervous tissue is found in the brain, spinal cord, and nerves. It is responsible for coordinating and controlling many body activities. It stimulates muscle contraction, creates an awareness of the environment, and plays a major role in emotions, memory, and reasoning. To do all these things, cells in nervous tissue need to be able to communicate with each other by way of electrical nerve impulses.

4. Epithelial-

Epithelial tissues are widespread throughout the body. They form the covering of all body surfaces, line body cavities and hollow organs, and are the major tissue in glands. They perform a variety of functions that include protection, secretion, absorption, excretion, filtration, diffusion, and sensory reception.