AP Biology Chapter 4

Chapter 4
Questions
1) How can carbon atoms form diverse molecules?
Carbon atoms can form diverse molecules by bonding to four other atoms.
2) What’re the three structures of isomers?
They are structural isomers, geometric isomers and enantionmers.
3) What’re the major elements of life?
C, H, O, N, S and P.

Factors
1) The form of carbon is 4 covalent bonds, its molecular shape is tetrahedral and it bonds easily to itself.
2) Isomers is something compounds with the same molecular formula but have different structures. There’re three types of isomers, they are structural isomers, geometric isomers and enantiomers.
3) Different chemical groups contribute to function by affecting the molecule’s shape. The chemical groups affect molecular function by being directly involved in chemical reaction; these important chemical groups are known as functional groups.
4) There are seven important functional groups, hydroxyl, carbonyl, carboxyl, amino, sulfhydryl, phosphate and methyl.
5) ATP also known as adenosine triphosphate, is a complicated organic phosphate.

Summary
Organic chemistry is the study of carbon compounds. Compounds containing carbon are said to be organic, and the branch of chemistry that specializes in the study of carbon compounds is called organic chemistry. Carbon atoms can form diverse molecules by bonding to four other atoms. A small number of chemical groups are keys to the functioning of biological molecules.

Diagram

In this diagram, we can see that both of the functions have hydroxyl function group. But they are in the different positions. So those two isomers are called geometric isomers.

Key terms
Hydrocarbon: organic molecules consisting of only carbon and hydrogen.

Organic chemistry: compounds containing carbon are said to be organic, and the branch of chemistry that specializes in the study of carbon compounds is called organic chemistry.

Methane: one carbon atom with four hydrogen atoms.

Ethane: two carbon atoms with six hydrogen atoms.

Ethane: two carbon atoms with four hydrogen atoms

Functional group: the chemical groups affect molecular function by being directly involved in chemical reactions; these important chemical groups are known as functional groups.

Structural isomers: differ in the covalent arrangements of their atoms.

Geometric isomers: have the same covalent partnerships, but they differ in their spatial arrangements.

Enantionmers are isomers that are mirror images of each other.

Amino acids: an organic molecule possessing both carboxyl and amino groups. Amino acids serve as the monomers of polypeptides.

video: http://www.youtube.com/watch?v=9JaYWEsT7fU

AP Biology Chapter 2

Chapter2
Questions
1) How a chemical connection to biology? (use a example)
The example in the book talked about the “devil’s gardens” In this forest, there’re just one kind of
trees, and they are well organized. Then scientists find out there’re a kind of ants they express a
poisonous chemical to stop other kinds of trees living in the forest. So in this forest, there’s just one
kind of tree called Duroia hirsute. From this case, we can see the chemical connection to biology.

2) What’re the main elements which make up 96% of living matter?
Carbon, oxygen, hydrogen, nitrogen

3) What’re the three kinds of subatomic particles?
Neutrons, protons, electrons.

The facts
1) The more distant an electron is from the nucleus, the greater its potential energy.

2) Atom is composed of subatomic particles.

3) Covalent bond, double covalent, hydrogen bond, van der waals interactions are all chemical
bonds.

4) All atoms of a particular element have the same number of protons in their nuclei.

5) Chemical reactions make and break chemical bonds.

Summary：
Matter consists of chemical elements in pure form and in combinations called compounds. Matter is made up of elements, and element is a substance that cannot be broken down to other substances. An element’s properties depend on the structure of its atoms. An atom is the smallest unit of matter that still retains the properties of an element. The formation and function of molecules depend on chemical bonding between atoms. There are four common chemical bonding between atoms, covalent bonds, ionic bonds, hydrogen bonds and van der Waals interactions. Chemical reactions make and break chemical bonds. In a chemical reaction, we have reactants and products.

From this diagram, we can see that one methane molecule and two oxygen molecules are the reactants. One carbon dioxide molecule and two water molecules are the products. In a chemical reaction, we use an arrow to indicate the conversion of the starting materials.

Key terms
Compound: is a substance consisting of two or more different elements combined in a fixed ratio
Neutron: a subatomic particle having no electrical charge, found in the nucleus of an atom.
Protons: a subatomic particle with a single positive electrical charge.
Electrons: a subatomic particle with a single negative electrical charge, one or more electrons move around the nucleus of an atom.
Dalton: a measure of mass for atoms and subatomic particles.
Atomic number: all atoms of a particular element have the same number of protons in their nuclei, the number of protons, which is unique to that element, is called the atomic number.
Mass number: is the sum of protons plus neutrons in the nucleus of an atom.
Radioactive isotopes: is one in which the nucleus decays spontaneously, giving off particles and energy.
Covalent bond: a covalent bond is sharing of a pair of valence electrons by two atoms.
Ionic bond: a chemical bond resulting from the attraction between oppositely charged ions.

video: http://www.youtube.com/watch?v=yjge1WdCFPs

AP Biology Chapter 1

Chapter 1
Introduction: Themes in the Study of Life
Question:
1) What are the levels in the biological hierarchy?(lowest to highest)


Molecules- Organelles- Cells- Tissues- Organs and Organ Systems- Organisms- Populations- Communities- Ecosystems- The Biosphere


2) The three domains of Life.
Bacteria, Archaea, Eukarya


3) What’re the two main forms of inquiry?
The discovery science, hypothesis –based science.

Factors
1, Scientists divide the enormous living things into different levels of biological organization.


2, Living things interact with the environments they live and exchange energy.


3, Scientists divide all living things in to different domains, kingdoms, phylum, class, order, family, Genus, Species. And there are three domains, Bacteria Archaea Eukarya.


4, Darwin published the theory of natural selection.


5, Scientists observe a phenomenon and give a question, then they used two main way to solve it. One called discovery science, another called hypothesis-based science.


Summary
In the chapter one, it introduced themes to us, which we knew they connect the concepts of biology. Evolution is an overarching theme of biology. And new properties emerge at each level in the biological hierarchy. There are about 10 different level in the biosphere which included biosphere and known as the highest level.
Organisms interact with their environments, exchanging matter and energy. Structure and function are correlated at all levels of biological organization. Cells are an organism’s basic units of structure and function. The continuity of life is based n heritable information in the form of DNA. Evolution accounts for the unity and diversity of life. Scientists use two main forms of inquiry in their study of nature.


Diagram
From this diagram, we can see the different levels of biological organization. They are Biosphere, Ecosystems, Communities, Population, Organisms, Organs and Organ Systems, Tissues, Cells, Organelles and Molecules. In this diagram, they used leaf as the example. We see the little leaf, but it is organ and organ systems. Below the leaf, there are tissues which are so tiny that we can’t see without microscope. And beyond the leaf, there’s a tree, it’s a individual living things which called organism. According to which level we are looking at, a leaf can very complicated as the whole biosphere, or very simple as a molecule.

Key terms

Emergent properties: new properties that arise with each step upward in the hierarchy of life, owing to the arrangement and interactions of parts as complexity increases.

Biosphere: the biosphere includes most regions of land, most bodies of water, and the atmosphere to an altitude of several kilometers.

Ecosystems: an ecosystem consists of all the living things in particular area, along with all the nonliving component of the environment with which life interacts.
Community: the entire array of organisms inhabiting a particular ecosystem is called biological community.

Populations: a population consists of all the individuals of a species living within the bounds of a specified area.

Organism: individual living things are called organisms.
Organs and organ system: the structural of life continues to unfold as we explore the architecture of the more complex organisms.

Tissues: an integrated group of cells with a common function, structure, or both.

Organelles: any of several membrane-enclosed structures with specialized functions, suspended in the cytosol of eukaryotic cells.

Feedback (negative, positive)
Negative feedback, in which accumulation of an end product of a process slows that process. (most common form of regulation)
Positive feedback, in which an end product speeds up its production.

video: http://www.youtube.com/watch?v=28ueTHq_fLw