AP Biology Chapter 7

Chapter 7
Question:
1) What’s phospholipids means?
A phospholipid is an amphipathic molecule, meaning it has both a hydrophilic region and a hydrophobic region.
2) Where the protein is located?
There are integral proteins and peripheral proteins. Integral proteins penetrate they hydrophobic core of the lipid bilayer. Peripheral proteins are appendages loosely bound to the surface of the membrane, often to exposed parts of integral proteins.
2) What called a electrogenic pump?
3) A transport protein that generates voltage across a membrane is called an electrogenic pump.

Factors
1) In the fluid mosaic model, the membrane is a fluid structure with a “mosaic” of various proteins embedded in or attached to a double layer (bilayer) of phospholipids.
2) Cells recognize other cells by binding to surface molecules, often to carbohydrates, on the plasma membrane.
3) They dye diffuses from where it is more concentrated to where it is less concentrated called diffusing down a concentration gradient.
4) To pump a solute across a membrane against its gradient requires work; the cell must expend energy. Therefore, this type of membrane traffic is called active transport.
5) A single ATP-powered pump that transports a specific solute can indirectly drive the active transport of several other solutes in a mechanism called cotransport.
Summary：
Cellular membranes are fluid mosaics of lipids and proteins. Membrane structure results in selective permeability. Passive transport is diffusion of a substance across a membrane with no energy investment. Active transport uses energy to move solutes against their gradients bulk transport across the plasma membrane occurs by exocytosis and endocytosis.

Diagram

In this diagram, I can see the different between hyperonic, isotonic and hypotonic. In hypotonic solution, the cells loose water molecules. In isotonic solution, the water molecule inside and outside of the cell are balanced. And in the hypotonic solution, the cells gain too much water which makes the cell explode.

Key terms
Osmosis: the diffusion of water across a selectively permeable membrane is called osmosis.

Isotonic: the isotonic to the cell means a cell without a wall, like an animal cell is immersed in an environment.

Hypertonic: when animal cell is immersed in a solution, it means hypertonic which the cell will lose water to its environment, shrivel and probably die.

Passive transport: the diffusion of a substance across a biological membrane is called passive transport.

Plasmolysis: as the plant cell shrivels, its plasma membrane pulls away from the wall, this phenomenon called plasmolysis.

Hypotonic: if we place the cell in a solution that is hypotonic to the cell, water will enter the cell faster than it leaves, and the cell will swell and lyse like an overfilled water ballon.

Active transport: to pump a solute across a membrane against its gradient requires work; the cell must expend energy, therefore, this type of membrane traffic is called active transport.

Facilitated diffusion: many polar molecules and ions impeded by the lipid bilayer of the membrane diffuse passively with the help of transport proteins that span the membrane. This phenomenon is called facilitated diffusion.

Peripheral proteins: they are not embedded in the lipid bilayer at all; they are appendages loosely bound to the surface of the membrane, often to exposed parts of integral proteins.

Integral proteins: they penetrate the hydrophobic core of the lipid bilayer.

video: http://www.youtube.com/watch?v=crpeX8nBgJE

AP Biology Chapter 5

Chapter 5
Questions
1) What’s condensation reaction?
Monomers are connected by a reaction in which two molecules are covalently bonded to each other through loss of a water molecule; this is known as a condensation reaction, specifically a dehydration reaction.
2) What’s the difference between saturated fat and unsaturated fat?
At room temperature, the molecules of a saturated fat such as butter are packed closely together, forming a solid. But at room temperature, the molecules of an unsaturated fat such as this olive oil cannot pack together closely enough to solidify because of the kinks in some of their fatty acid hydrocarbon chains.
3）what’s phospholipids?
Phospholipids are essential for cells because they make up cell membrane.


Factors
1） The simplest carbohydrates are the Monosaccharides, also known as simple sugars. Disaccharides are double sugars consisting of to monosaccharides joined by a covalent bond.
2） Depending on the location of the carbonyl group, a sugar is either an aldose (aldehyde sugar) or a ketose (ketone sugar).
3) Some polysaccharides serve as storage material, hydrolyzed as needed to provide sugar for cells. Other polysaccharides serve as building material for structures that protect the cell or the whole organism.
4) Lipids are the one class of large biological molecules that does not include true polymers, and they are generally not big enough to be considered macromolecules.
5) All proteins share three superimposed levels of structure, known as primary, secondary, and tertiary structure. A fourth level, quaternary structure, arises when a protein consists of two or more polypeptide chains.



Summary:
Macromolecules are polymers, build from monomers. Carbohydrates serve as fuel and building material. Lipids are a diverse group of hydrophobic molecules. Proteins have many structures, resulting in a wide range of functions. Nucleic acids store and transmit hereditary information.



Diagram
When a bond forms between two monomers, each monomer contributes part of the water molecule that is lost: one molecule provides a hydroxyl group (-OH), while the other provides hydrogen (-H). This reaction can be repeated as monomers are added to the chain one by one, making a polymer.

Key terms
Monosaccharide: The simplest carbohydrates.

Glucose: Most common monosaccharide.

Sucrose: The most prevalent disaccharide.

Lipid: they are the one class of large biological molecules that does not include true polymers, and they are generally not big enough to be considered macromolecules.

Fatty acid: a long carbon chain carboxylic acid.

Polypeptide: polymers of amino acids are called polypeptides.

Amino acids: its organic molecules possessing both carboxyl and amino groups.

Cholesterol: It’s a common component of animal cell membranes and is also the precursor from which other steroids are synthesized.

Glycogen: animals store a polysaccharide called glycogen, a polymer of glucose that is like amylopectin but more extensively branched.

Polynucleotide: nucleic acids are macromolecules that exist as polymers called polynucleotide.

video: http://www.youtube.com/watch?v=7k2KAfRsZ4Q

AP Biology Chapter 8

Chapter 8
1) What does the second law of transformation means?
It means every energy transfer or transformation increases the entropy of the universe. It’s like when we light a candle, the candle’s burning. The potential energy of candle is losing, but these potential energy changes into some disorder energy go back to universe.
2) What means free energy?
Free energy is the portion of system’s energy that can perform work when temperature and pressure are uniform throughout the system, as in a living cell.
3) what’s the name of ATP
Adenosine triphosphate. In the ATP, there are adenine (nitrogenous base), ribose (pentose sugar) and 3 phosphates.

Factors
1) Some metabolic pathways release energy by breakdown complex molecules to simpler compounds; these degradative processes are called catabolic pathways. Anabolic pathway is to consume energy to build complicated molecules from simpler ones. Catabolic pathways store energy and anabolic pathway release those energy.
2) Energy is the capacity to cause change. There are three different types of energy, kinetic energy, potential energy and chemical energy.
3) There’re two laws of transformation. One is the energy of the universe is constant, energy can be transferred and transformed, but it cannot be destroyed or created. It also known as the principle of conservation of energy. Second law is every energy transfer or transformation increases the entropy of the universe.
4) There are 3 things that can affect enzyme activity. They are temperature and PH which we conclude as environment. And cofactors, enzyme inhibitors.
5) In feedback inhibition, a metabolic pathway is switched off by the inhibitory binding of its end product to an enzyme that acts early in the pathway.
Summary:
An organism’s metabolism transforms matter and energy, subject to the laws of thermodynamics. The free-energy change of a reaction tells us whether or not the reaction occurs spontaneously. ATP powers cellular work by coupling exergonic reactions to endergonic reactions. Enzymes speed up metabolic reactions by lowering energy barriers. Regulation of enzyme activity helps control metabolism.

Diagram
This is an ATP cycle picture. It shows how ATP works in cell. Enery released by breakdown tractions (catabolism) in the cell is used to phosphorylate ADP, regenerating ATP. Chemical potential energy stored in ATP drives most cellular work.

Key terms
Metabolism: an emergent property of life that arises from interactions between molecules within the orderly environment of the cell.

Bioenergetics: the study of how energy flows through living organisms.

Chemical energy: the term people use to refer to the potential energy available for release in a chemical reaction.

Thermodynamics: the study of the energy transformations that occur in a collection of matter.

Free energy: is the portion of a system’s energy that can perform work when temperature and pressure are uniform throughout the system, as in a living cell.

Exergonic reaction: An exergonic reaction proceeds with a net release of free energy.

Endergonic reaction: An endergonic reaction is one that absorbs free energy from its surroundings.

Active site: only restricted region of enzyme molecule actually binds to the substrate, this region, called the active site.

Competitive inhibitor: they reduce the productivity of enzymes by blocking substrates from entering active sites.

Noncompetitive inhibitor: they do not directly compete with the substrate to bind to the enzyme at the active site; instead they impede enzymatic reactions by binding to another part of the enzyme.

Video: http://www.youtube.com/watch?v=Ki9Tly-A-Rc

AP Biology Chapter 6

Chapter 6
Question
1) What are the different microscopes?
They are, light microscope (LM), electron microscope (EM). And there are two different types of electron microscopes; they are scanning electron microscope (SEM) and transmission electron microscope (TEM).
2) What’s the function of Golgi Apparatus?
The Golgi apparatus is shipping and receiving center, such as the products of ER are modified and stored and then sent to other destinations, all those steps are taking place in Golgi apparatus.
3) What’s the function of smooth ER?
The smooth ER functions in diverse metabolic processes, which vary with cell type. These processes include synthesis of lipids, metabolism, of carbohydrates, and detoxification of drugs and poisons.
Factors
1) Scanning electron microscope (SEM) shows the surface of a cell, and it can be used on the living cells. Transmission electron microscopy (TEM) shows the inside of the cells, it’s used on dead cells.
2) There’s nucleus inside of eukaryotic cells, but not inside of prokaryotic cells. And the nucleus is bounded by a double membrane. DNA is concentrated in a region that is not membrane enclosed, called nucleoid.
3) The organelles are both in animal cell and plant cell.
Endoplasmic reticulum(ER), there are rough ER (contain ribosome) and Smooth ER. Golgi apparatus is used to package and store the products from in the cell. Ribosomes are used to make proteins. Mitochondrion is the organelle where cellular respiration occurs and most ATP is generated. Plasma membrane.
4) The organelles are either in the animal cell or in the plant cell.
Lysosomes are digestive organelle where macromolecules are hydrolyzed. Centrosome is the region where the cell’s microtubules are initiated. (In animal cells)
Chloroplasts are photosynthetic organelle. Central vacuole (single membrane) is used to store food and water. Cell wall can maintain cell’s shape and protect cell from mechanical damage, made of cellulose, other polysaccharides and proteins. Plasmodesmata are the channels through cell walls that connect the cytoplasm of adjacent cells. (In plant cells)
5) Mitochondria are found in nearly all eukaryotic cells. It is enclosed by two membranes, each a phospholipids bilayer with a unique collection of embedded proteins.

Summary
Biologists use microscopes and the tools of biochemistry. Eukaryotic cells have internal membranes that compartmentalize their functions. The eukaryotic cell’s genetic instructions are housed in the nucleus and carried out by the ribosomes. The endomembrane system regulates protein traffic and performs metabolic functions in the cell. Mitochondria and chloroplasts change energy from one form to another. Thy cytoskeleton is a network of fibers that organizes structures and activities in the cell. Extracelular components and connections between cels help corordinate cellular activities.
Diagram
From this diagram, we can see there’re endoplasmic reticulum, golgi apprartus, ribosomes, mitochondrion and plasms membrane in both animal cell and plant cell. However, there are lysosomes, centrosome are just in animal cell and chloroplasts, central vacuole, cell wall and plasmodesmata in plant cell.

Key terms

Cytosol: the liquid inside of cells.

Cytoplasm it is the contents of the cell, exclusive of the nucleus and bounded by the plasma membrane.

Chromosomes: A cellular structure carrying genetic material, found in the nucleus of eukaryotic cells.

Chromatin: The complex of DNA and protein that makes up a eukaryotic chromosome.

Ribosome: A complex of rRNA and protein molecules that functions as a site of protein synthesis in the cytoplasm.

Vesicle: A sac made of membrane in the cytoplasm.

Peroxisome: peroxisomes are roughly spherical and often have a granular or crystalline core that is thought to be a dense collection of enzyme molecules.

Flagella: A long cellular appendage specialized for locomotion.

Cilia: A short cellular appendage containing microtubules.

Lysosome: A membrane-enclosed sac of hydrolytic enzymes found in the cytoplasm of animal cells and some protests.

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

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 3

Chapter3
Questions
1) How did water go up to leaves in the tree?
Water from the roots reaches the leaves through a network of water-conducting cells. As water evaporates from a leaf, hydrogen bonds cause water molecules leaving the veins to tug on molecules farther down, and the upward pull is transmitted through the water-conducting cells all the way to the roots. The hydrogen bonds hold the substance together, a phenomenon called Cohesion.
2) The difference between hydrophilic and hydrophobic substances
The simple way to tell hydrophilic and hydrophobic is to see if the substance will dissolve in the water or not. Hydrophilic substance dissolves in the water, and hydrophobic substance doesn’t. However, there’re some substance can be hydrophilic without dissolving in water, such as colloid. Colloid molecule is too big to dissolve, so it will just remain suspended in the aqueous liquid of the cell.
3) What are the bonds of water molecules?
They are covalent bonds and hydrogen bonds. Inside the water molecule, they use covalent bonds to connect oxygen and hydrogen, but between water molecules, they use hydrogen bonds to link to each other.

Factors
1) Water molecules are shaped something like a wide V, with its two hydrogen atoms joined to the oxygen atom by single covalent bonds.
2) The hydrogen bonds hold the substance together, a phenomenon called Cohesion. The clinging of one substance to another is called Adhesion.
3) An acid is a substance that increases the hydrogen ion concentration of a solution. A substance that reduces the hydrogen ion concentration of a solution is called a base.
4) A liquid that is a completely homogeneous mixture of two or more substances is called a solution, the dissolving agent of a solution is the solvent, and the substance that is dissolved is the solute.
5) Heat is a form of energy


Summary:
They polarity of water molecules results in hydrogen bonding. The unequal distribution of electrons makes water a polar molecule, meaning that the two ends of the molecule have opposite charges. Four emergent properties of water contribute to earth’s fitness for life. They are cohesion and adhesion, high specific heat of water, solvent of life and fluidity. Acidic and basic conditions affect living organisms.

Diagram
From the diagram, we can see the water molecules are boned together by hydrogen bond and inside of the water molecules, the hydrogen atom bonded with oxygen atom by covalent bond. The charged regions of a polar water molecule are attracted to oppositely charged parts of neighboring molecules.

Key terms

Cohesion: they hydrogen bonds hold the substance together, a phenomenon called cohesion.

Adhesion: the clinging of one substance to another called adhesion.

Surface tension: it is related to cohesion, a measure of how difficult it is to stretch or break the surface of a liquid.

Specific heat: the specific heat is defined as the amount of heat that must be absorbed or lost for 1g of that substance to change its temperature by 1C.

Hydrophobic: having an aversion to water; tending to coalesce and form droplets in water.

Hydrophilic: having an affinity for water.

Solution: a liquid that is a homogeneous mixture of two or more substances.

Solute: a substance that is dissolved in a solution.

Aqueous solution: a solution in which water is the solvent.


video:http://www.youtube.com/watch?v=CT4pURpXkbY

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