Compendium #1

Table of Contents:

EXPLORING LIFE AND SCIENCE

1. Characteristics of Life
a. Organization
2. Humans Related to Other Animals
a. How we are classified

3. Science as a Process

a. Scientific Method

b. Controlled Study

4. Make Sense of Scientific Study
a. Graphs

5. Science and Social Responsibility

a. Conclusion

CHEMISTRY OF LIFE

6. From Atoms to Molecules
a. Elements

b. Atoms

c. Isotopes

d. Molecules and Compounds

7. Water and Living Things

a. Hydrogen bonds

b. Properties of Water
c. Acids and Bases

8. Molecules of Life

a. Organic molecules

9. Carbohydrates

a. Simple

b. Complex

10. Lipids

a. Fats and oils

b. Dietary Fat

c. Phospholipids

11. Proteins

a. Importance of

b. Amino Acids

c. Shapes of

d. Levels of organization

12. Nucleic Acid

a. DNA and RNA

b. ATP

CELL FUNCTION AND STRUCTURE

13. What is a cell

a. cell theory and size

14 How cells are organized

15. Plasma Membrane and How Substances Cross It

a. four types or ways of transport

16. Nucleus and Production of Proteins

a. Nucleus

b. Ribosomes

c. endomembrane system

17. Cytoskeleton and Cell Movement

a. Cilia and Flagella

18. Mitochondria and Cellular Metabolism

a. Cell Respiration and Metabolism

b. Fermentation

ORGANIZATION AND REGULATION OF BODY SYSTEMS

19. Types of Tissues

a. 4 types

20. Connective tissue Connects and Supports

a. Fibrous

b. Supportive

c. Bone

d. Fluid

21. Muscular Tissue Moves the Body

a. Skeletal

b. Smooth

c. Cardiac

22. Nervous Tissue Communicates

a. Neurons

b. Neuroglia

23. Epithelial Tissue Protects

a. Simple

b. Pseudostratified

c. Transitional

d. Stratified

e. Glandular
24. Cell Junctions

a. Tight

b. Adhesion

c. Gap

25. Integumentary

a. 2 regions of skin

b. 4 accessory organs

26. Organ systems

a. 11 systems

b. body cavities

27. Homeostasis

a. Internal Environment

b. Body Systems and homeostatsis

c. Negative feedback

d. Positive feedback

EXPLORING LIFE AND SCIENCE

Characteristics of Life

In chapter 1 the basic characteristics of life were covered. Living things are: organized, take material from environment, reproduce, grow and develop, homeostatic, respond to stimuli, and have evolutionary history.

Below is a chart of how life is organized.*

Atoms are the smallest unit of an element composed of electrons, protons, and neutrons. Atoms joined together form molecules. Molecules form the cells, which are the structural and functional unit of all living things. Now, humans are multicellular because are bodies are composed of many different types of cells. Cells then come together to form tissue. Tissue is a group of cells with a common structure and function, ie. nerve tissue. Tissues then make up an organ which are tissues functioning together for a specific task. Organs are all a part of an organ system which is several organs working together. That takes to organisms which is a collection of organs, for ie. a human or tree. The chart also takes us into biological organization. All members of one species belong to a population. A community is formed when there are interacting populations in an area. Communities form ecosystems, which is the community plus the physical environment. Which then takes us to biosphere which is the Earth that is inhabited by living things.

As living things we 1. acquire materials and energy. We get most of our energy from food 2. reproduce- create copy of selves. 3. grow and develop- changes through life 4. homeostatic - we maintain normal internal conditions by means of self-regulating mechanisms 5. we respond to stimuli- like sight of food 6. we have evolutionary history - a species change through time. This helps living things adapt to surroundings and pass on learned things to next generations.

Humans are Related to Other Animals

Here is a chart to show how humans are classified.*

By showing this chart I hope it shows you how we are classified and it explains or shows it better than I would be able to. Humans are vertebrates in the kingdom, Animalia. This means we have a nerve cord protected by vertebral column. We are also mammals, we have hair and mammary glands. Humans are distinguished by their highly developed brains, complete upright stance, creative language , and ability to use a wide variety of tools.

Science as a Process

Now on to science as a process. Scientific theories are concepts that tell us about the order and the patterns within the natural world. Scientific method is the process that scientific information is acquired. The picture* here on the left shows the steps of that method. First, an observation is made and previous data is studied. Second, a hypothesis is formed, a testable statement. Third, the experiments and observations are done and made. Next is the conclusion, where results are analyzed, and the hypothesis is supported or rejected. The next picture* shows the steps and findings of a controlled study. Which includes an experiment, experiment variables, a control group and test groups. And shows that placebos are also used.

Make Sense of Scientific Study

To make sense of scientific study beware of anecdotal and correlation data. This data still needs further study. Using bar and line graphs to show relationship between quantities.

Science and Social Responsibility

In conclusion to this chapter science and our social responsibility are somewhat linked. Scientific information is based on observation and experimentation. Scientists therefore need not to make value judgements for us. Using technology has its risks and we all need to make informed decisions regarding how technology should be used. We need to take active roles in to help preserve biodiversity. Now we will take a look at the chemistry of life.

CHEMISTRY OF LIFE

From Atoms to Molecules

Anything that takes up space and has mass is matter. Elements are a basic building block of matter. Elements cannot be broken down by chemical means. Elements are all made up of one atom. Atoms are made up of protons and neutrons that are in the nucleus. The electrons actually orbit around the nucleus in shells. Protons,which are + charge, and neutrons, which are a - charge, determine the weight of an atom, depending on how many of them there is. The atoms chemical properties come from how many electrons, which have - charge also, are orbiting around the nucleus. The chart below shows subatomic particles and their atomic mass.*

An isotope is one of two or more atoms with same atomic number but a different atomic mass due to the number of neutrons.

Molecules are when atoms bond with one another to form a chemical unit. These can contain atoms of the same kind. Oxygen will sometimes bond with other oxygen atoms to form oxygen gas. When different atoms join this is called a compound. There are two different bonds that join atoms. One is called ionic. Ions are particles that have a - or + charge. Ionic bonds are formed when oppositely charged ions are attracted to each other. For example, sodium and chloride, then giving us table salt. The second bond is covalent. In this bond atoms share electrons, in ionic atoms take or give up electrons to have a stable outer shell. Here are some examples of both kinds of bonds.*

Water and Living Things

First of all, water is the most abundant molecule in living organisms, we are about 60-70% water. Water is a polar molecule, which says the oxygen end of the molecule has a slight negative charge while the hydrogen end has a slight positive charge. There is an example in the picture below.

There are many properties of water because of the polarity and hydrogen bonding. There are 6 properties: 1. water is a liquid at room temp. 2. water freezes and heats slowly 3. moderates temp. and allows us to vaporize water to keep our bodies cool 4. frozen water is less dense than liquid water, that's why it floats 5. water is cohesive and fills tubular vessels 6. water is the universal solvent because of its polarity. Water has a neutral pH.

Molecules of Life

Organic molecules include carbohydrates, lipids, proteins and nucleic acids. Organic refers to a molecule that contains carbon and hydrogen and is usually associated with living things.

Carbohydrates

Carbohydrates function for quick and short term energy storage in all organisms. There are two forms of carbohydrates: Simple and Complex. Simple carbohydrates are mono saccharides. The glucose is a 6 carbon sugar used for quick energy. Complex carbohydrates are polysaccharides. These consist of starch, glycogen and cellulose.

Lipids

Lipids contain more energy than any other molecule. Fats and oils are both lipids. Fats are from animals and oils are usually plant based. Fatty acids can be saturated or unsaturated.

Plasma membranes contain phosopholipids. Steroids are also part of the lipid group and two of these are testosterone and estrogen.

Proteins

Protein is important in our bodies and function and structure of our cells. First, they help provide support, ie with our hair and nails, keratin. Second, they are enzymes that help speed up chemical reactions in cells. Thirdly, they help transport substances in and out of the cells, ie hemoglobin helps transport oxygen. Fourth, antibodies are proteins that help with defense in our bodies. Fifth, hormones help regulate, ie insulin. Last, they help with motion, actin and myosin.

Protein are macromolecules with amino acid subunits. A peptide is two amino acids. A polypeptide contains many amino acids. A protein has levels of organization which are shown here in the illustration.*

Nucleic Acids

There are two types of nucleic acids, DNA and RNA which are polymers of nucleotides. Nucleic acids are macromolecules composed of nucleotides. Nucleotides are composed of sugar, a base, and a phosphate. The DNA contains the sugar deoxyribose and the RNA contains the ribose.

ATP(adenosine triphosphate) molecule is unstable because of it bonds making it a high energy molecule. ATP forms when glucose is broken down.

In conclusion to this chapter are body needs a lot of different things to survive. Without any of these atoms and molecules like, carbs, lipids, proteins, nucleic acids and obviously water our bodies would not survive. Its amazing the little things that we don't really think about everyday keep our cells alive and thriving. We are so complex as beings that we know these things go on in our bodies, but we don't need to "make" them happen they just do.

CHEMISTRY OF LIFE

Cell Function and Structure

What is a Cell?

A cell is the basic unit of life. They come from preexisting cells. We view cells by looking through a microscope. Cells must stay small to have a more favorable surface-area-to-volume ratio. They need less nutrients. With a small area it is easier for nutrients and wastes to enter and leave the cell.

How Cells are Organized

There are two different cells addressed here. Eukaryotic and prokaryotic. The main difference between the two is prokaryotic cella lack a nucleus, where DNA is found. Eukaryotic has a nucleus. Both kind of cells contain a plasma membrane and a cytoplasm, where organelles are contained.

The Plasma Membrane and How Substances Cross It

The plasma membrane is a phospholipid bilayer. It allows only certain molecules to enter and exit the cytoplasm. The proteins that are in the membrane help some substances cross. The passage of molecules is either passive or active. Passive is there is no energy required. Diffusion is one way of passive entry or exit of cells. Osmosis is diffusion of water across the membrane. Facilitated transport is done with the help of protein carriers within the membrane. Active transport requires a protein carrier and cellular energy. When endocytosis and exocytosis occur the plasma membrane forms a pouch to envelop a substance and fluid. The picture to the left show this process.*

The Nucleus and the Production of Proteins

The nucleus houses the DNA, genetic information. Chromatin is inside the nucleus also, it also contains DNA. Chromatin then coils into chromosomes before cell divides. The nucleolus contains rRNA. Ribosomes are organelles composed of proteins and rRNA. Protein synthesis occurs at the ribosomes.

The endomembrane system consists of the nclear envelope, endoplasmic reticulum (er), golgi apparatus, lysosomes and vesicles. Rough ER has ribosomes. Smooth ER has no ribosomes and has various functions. The Golgi apparatus processes and packages proteins and lipids into vesicles for secretion or movement into other parts of the cell. Lysosomes are specialized vesicles produced by the Golgi apparatus.

The Cytoskeleton and Cell Movement

The cytoskeleton has microtubules, actin filaments, and intermediate filaments that gibe cells their shape and allows organelles to move about the cell. Cilia and flagella allow the cell to move. An example to the left.*

Mitochondria and Cellular Metabolism

Mitochondria are considered the power house of the cell. It burns converts chemical energy from glucose products. Mitochondria use up oxygen and give off carbon dioxide. This process is called cellular respiration as seen here in the illustration.* This illustration also goes through the steps of cellular repiration.

Cellular respiration is the enzymatic breakdown of glucose to carbon dioxide and water. Cellular respiration also has 3 pathways. Glycolysis, which occurs in cytoplasm. Citric acid cycle, which releases carbon dioxide. Electron transport chain, which passes electrons to oxygen.

Fermentation is anaerobic process, it does not require oxygen. Fermentation produces very little ATP.

For the end of this chapter, the cell is an amazing living thing. We take for granted all these little things because we do nothing to make these cells reproduce.

ORGANIZATION AND REGULATION OF BODY SYSTEMS

Types of Tissue

There are 4 types of tissue: Connective, Muscular, Nervous, and Epithelial. In the following paragraphs we will take a closer look at them.

Connectvie Tissue

Connective tissue binds and supports body parts. There are 4 different types of connective tissue. 1. Fibrous connective tissue. a. Loose fibrous supports epithelium and mnay internal organs. It helps our lungs, bladder, arteries expand. b. Adipose is also loose fibrous tissue and it makes the cells enlarge in order for them to store fat. c. Dense fibrous cotains collagen fibers that are found in tendons and ligaments. 2. Supportive connective tissue which is cartilage. a. Hyaline cartilage is the most common cartilage. It is found in the nose, and at the end of long bones and the ribs. The fetal skeleton is also made from hyaline cartilage. b. Elastic cartiage is more flexible and is found in the framework of the outer ear. c. Fibrocartilage contains strong collagen fibers which can withstand tension and pressure. It is located as the diske=s between vertebrae in the backbone and the wedges in the knee joint. 3. Bone is the most rigid of these tissues. a. Compact bone makes up the shaft of a long bone. b. Spongy bone is located at the ends of a long bone. 4. Fluid connective tissues. a. Blood which is in our blood bessels. Blood transports nutrieients and oxygen to tissue fluid. b. Lymph is a clear, watery, sometimes faintly yellowish fluid that contains white blood cells.

Muscular Tissue Moves the Body

There are 3 types of muscular tissue. 1. Skeletal which is called a voluntary muscle. This is attached by tendons to the bones of the skeleton. 2. Smooth or visceral, is said it be involuntary and it is found in the walls of the intestine, bladderm and other internal organs, and blood vessels. 3. Cardiac is found only in the walls of the heart. Cardiac muscle is a combination of skeletal and smooth muscle.

Nervous Tissue Communicates

Nervous tissue consists of nerve cells,neurons, and neuroglia. Neurons are specialized cell that has three parts, dendrites, a cell body and an axon. Neuroglia are cells that outnumber neurons nine to one and take up more than half the volume of the brain.

Epithelial Tissue Protects

Epithelial tissue consists of tightly packed cells that form a continuous layer. There are 5 types of epithelial tissue.

1. Simple has a single layer of cells. a. squamous epithelium is flattened cells found in the air sacs of lungs and walls of blood vessels. b. cuboidal epithelium has single layer of cube-shaped cells. This is found in salivary glands, thyroid gland and pancreas. c. columnar epithelium has cells resembling rectangular pillars with nuclei located at the bottom of each cell. This is found in the lining of the digestive tract. 2. Pseudostratified columnar appears to be layered. No true layers exist. This is found in the lining of the windpipe. 3. Transitional implies changeability, theis tissue changes in response to tension. It is found in the lining of the urinary bladder, the ureters, and part of the urethra. 4. Glandular epithelia secretes a product. A gland can be single epithelial cell, or can contain many cells. These include exocrine glands, e.g. pancreas, and endocrine glands, e.g. pituitary gland and thyroid.

Cell Junctions

Cell junctions help a tissue perform is funtion. Cell junctions join cells together into a cohesive hold. There are 3 different types of junctions. 1. Tight junctions allow epithelial cells to forma layer that covers the surface of organs and lines body cavities. 2. Adhesion junctions firmly attach cytoskeletal fibers of one cell to that of another cell. 3. Gap junctions occur when adjacent plasma membranes converge and leave a tiny channel between them. Refer to illustration on left for a better understanding.*

Integumentary System

The skin has many accessory organs and therefore is sometimes referred to as the integumentary system.

There are 2 Regions of skin. 1. Epidermis which is made of stratified squamous epithelium. This is the very first layer of skin. 2. Dermis is made of dense fibrous connective tussue beneath the epidermis.

There are 3 accessory organs of the skin. 1. Nails which is a protective covering of the end of fingers and toes. 2. Hair follicles 3. Glands a. oil glands which secrete sebum and lubricates the hair within the follicle and the skin itself. b. Sweat glands help in modifying body temperature.

Organ Systems

There are 11 organ systems in the body.

Illustration to left*

1. Integumentary system- skin 2. Cardiovascular system - heart, blood bessels 3. Lymphatic and Immune system - lymph nodes, spleen

4. Digestive system - mouth, esophagus, stomach, small intestine, large intestine 5. Respiratory system - lungs and tubes that move air from them 6. urinary system - kidneys, urinary bladder.

Illustration to left*

7. Skeletal system - protects body parts 8. Muscular system 9. Nervous system - brain, spinal cord, and associated nerves 10. Endocrine system - hormonal glands11. Reproductive system.

Body Cavities

The body is divided into two main cavities: the ventral and dorsal. Ventral contains thoracic cavity, abdominal cavity, pelvic cavity. Dorsal contains cranial cavity and vertebral cavity. See illustration to left for different parts.*

Homeostasis

Homeostasis is the relative constancy of the internal environment, which is tissue fluid and blood. All organ systems contribute to homeostasis.

Negative feedback mechanisms keep the environment relatively stable. Examples would be regulation of blood glucose level by insulin, regulation of room temperature and regulation of body temperature by the brain and sweat glands.

Positvie feedback mechanism brings about rapid change in the same direction as the stimulus and does not achieve relative stability. For example, these mechanisms are useful under certain conditions like giving birth.

Our bodies are amazing things. From the cell all the way up to the organ systems. There are so many things that happen from the top of our skin all the way down to our insides and so complex. I am glad our bodies were made to function with such finesse. Our bodies are amazing.

*All pictures came from this website.

http://highered.mcgraw-hill.com/classware/ala.do?isbn=0072986867&alaid=ala_1013206&showSelfStudyTree=true