Jack Bowers Chapter 2 Biology Notes

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Jack Bowers’ Chapter 2 Biology Notes

v  Three parts of an atom: electrons, neutrons, and protons.

v  Difference between ionic and covalent bonds: An ionic bond is formed by the attraction between ions (formed by the gain/loss of electrons,) while a covalent bond is formed by the sharing of electrons between atoms.

v  Polar molecule: A molecule with both negatively and positively charged regions. A common example is water.

v  Solute and Solvent: A solvent dissolves a solute and is found in the greater amount, and solutes dissolve in a solvent. Together, they make up a solution.

v  Draw glucose: (C6/H12/O6)

v  A monomer is a molecular subsection, and a polymer is a group of combined monomers.

v  Lipid: Nonpolar molecules that include fats, oils, and cholesterol.

v  High temperature and ‘Ph’ change the structure of enzymes.

v  A catalyst is an enzyme in living things, and its functions are to reduce activation energy and increase chemical reaction duration.

v  A protein is a polymer made up of amino acid monomers.

v  Proteins differ in the order and number of amino acids they contain.

v  Ions are molecules that have become charged, negatively or positively, because of the gain or loss of electrons.

v  A hydrogen bond is an attraction between a hydrogen atom (+) and a negative atom.

v  An acid is a compound t at releases a hydrogen ion (+) when dissolving in water, and increases the concentration of hydrogen ions (+) in a solution. On the other hand, bases are compounds that remove hydrogen ions (+) from a solution. A solution’s acidity is measured by Ph, or its hydrogen ion concentration.

v  When a chemical reaction is sketched, reactants are placed on the left side, and the products are placed on the right side.

v  An exothermic reaction releases more energy than it absorbs, and an endothermic reaction absorbs more energy than it releases.

v  Monosaccharides are simple sugars, and polysaccharides are starches.

v  An unsaturated fat is liquid at room temperature, while a saturated fat is a solid at room temperature.

v  Phospholipid: Has fatty acid ‘tails’ and a polar ‘head’ that contains a phosphate group.

Jack Bowers

10.14/15.2008

Biology Chapter 3 Notes

·  Organelles enable eukaryotic cells to carry out specialized functions.

·  Animal cells are eukaryotic

·  Prokaryotic cells do not have organelles

·  Eukaryotic cells have organelles

·  Phospholipids combine to create the double layer that is a cell membrane

·  Ligands are also known as signal molecules

·  The nucleus’ double membrane is known as the nuclear membrane

·  The nucleolus produces RNA and ribosomes

·  RNA is used to make proteins

·  Vesicles are organelles that transport cell materials and are involved in endocytosis and exocytosis

·  Endocytosis is the movement of materials, that are too large for diffusion, into a cell by use of vesicles

·  Proteins and polysaccharides are brought into a cell by endocytosis

·  Exocytosis is the movement of materials, such as waste and other things too large for diffusion, out of a cell by use of vesicles

·  A cell that requires large amounts of energy likely has a large quantity of mitochondria

·  Chloroplasts are organelles involved in the process of photosynthesis

·  Only plants, bacteria, and algae have cell walls

·  Bacteria are prokaryotic cells

·  Passive transport is the movement of molecules across the cell membrane that does not require the use of cell energy

·  Diffusion, a type of passive transport, is the movement of molecules across a cell membrane from higher to lower concentration regions (down the concentration gradient)

·  Diffusion through ion channels is passive transport

·  Facilitated diffusion, a type of diffusion, is diffusion made easier by the use of transport proteins

·  Transport proteins are also known as channel proteins, protein channels, or carrier proteins

·  Osmosis, a type of passive transport and diffusion, is the movement of water across a cell membrane

·  Water does not need a protein channel to cross a cell membrane

·  Active transport is the movement of molecules across a cell membrane, from low to high concentration regions, that requires energy from the cell (against concentration gradient)

·  Most of a cell’s energy is produced by mitochondria

·  Mitochondria and chloroplasts have DNA

·  Plant cell analogy: Shoe Box

o  The cardboard box is like the cell wall

o  The plastic bag inside the cardboard box is like the cell membrane

·  Marker proteins, made partially of carbohydrate chains, are located on the outside of the cell and serve as identification tags

·  Receptor proteins are found in the membrane

·  Receptors bind with ligands, also known as signal molecules, and change in shape

·  There are two types of signal molecules:

o  Intracellular: Inside the cell

o  Membrane: In the membrane

·  Chemical signals are transmitted across the cell membrane by signal molecules

·  Receptor proteins bond to signal molecules (ligands) outside the cell

Chapter 5 Notes – Jack Bowers

·  Mitosis: Process by which a cell divides its nucleus and contents

o  Body Cells (somatic) are produced

o  Starts with one cell, ends with two cells

o  Each cell has 46 chromosomes (23 pairs)

o  The 46 chromosomes come in pairs called homologous pairs

o  Each of the two resulting cells has forty-six chromosomes, just like the parent cell

o  Metaphase: The pair of sister chromatids stack

o  The sister chromatids split into chromatids in anaphase

o  Process of mitosis: IPMAT

§  Interphase: Cell continues normal functions

§  Prophase: Chromosomes form and become visible

§  Metaphase: Chromosomes attach to spindle fibers and align along the middle of the cell

§  Anaphase: Nucleus starts to be divided

§  Telophase: The nucleus continues to divide, with a pinch between the two new nuclei becoming visible

·  Cytokinesis: Stage at which two daughter cells are formed

·  In asexual reproduction,

·  Meiosis: Cell division involving gametes

o  Starts with one cell, and ends in four cells

o  Each resulting cell has the original 23 chromosome pairs

o  The sister chromatids stay connected at the centromere in anaphase

o  Goes through two divisions: one cell – two cells – four cells

·  Anaphase: Third phase of mitosis in which chromatides separate and are pulled to opposite sides of the cell

·  Apoptosis: Programmed cell death

·  Asexual reproduction: Process by which offspring are produced from a single parent; does not involve the joining of gametes

·  Benign: Having no dangerous effect on health, especially referring to abnormal growth of cells that are not cancerous

·  Binary Fission: Asexual reproduction in which a cell divides into two equal parts

·  Cancer: Common name for cell division characterized by uncontrolled cell division.

·  Carcinogen: Substance that improves or promotes the development of cancer

·  Cell cycle: Pattern of growth, DNA replication, and cell division that occurs in a eukaryotic cell

·  Cell differentiation: Process by which unspecialized cells develop into their mature form and function

·  Centromere: Region of condensed chromosomes that looks pinched; where spindle fibers attach during meiosis and mitosis

·  Chromatid: One half of a duplicated chromosome

·  Chromatin: Loose combination of DNA and proteins that is present during interphase

·  Chromosome: Long, continuous strand of DNA that consists of numerous genes and regulatory information

·  Cytokinesis: Process by which cell cytoplasm divides

·  Growth Factor: Broad group of proteins that stimulate cell division

·  Histone: Protein that organizes chromosomes and around which DNA wraps

·  Malignant: Cancerous tumor in which cells break away and spread to other parts of the body; causing harm to the organism’s health

·  Metaphase: Second phase of mitosis when spindle fibers align the chromosomes along the cell equator

·  Metastasize: To spread by transferring a disease – causing agent from the site of disease to other parts of the body

·  Organ: Group of different types of tissue that work together to perform a specific function or related functions

·  Organ system: Two or more organs that work in a coordinated way to carry out similar functions

·  Prophase: First phase of mitosis when chromatin condenses, the nuclear envelope breaks down, the nucleolus disappears, and the centrosomes and centrioles migrate to opposite sides of the cell

·  Stem cell: Cell that can divide for long periods of time while remaining undifferentiated

·  Telomere: Repeating nucleotide at the ends of DNA molecules that do not form genes and help prevent the loss of genes

·  Telophase: Last phase of mitosis when a complete set of identical chromosomes is positioned at each pole of the cell, the nuclear membranes start to form, the chromosomes begin to uncoil, and the spindle fibers disassemble

·  Tissue: Group of cells that work together to perform a similar function

·  Section 5.1 Quiz:

o  DNA is copied during the Synthesis stage of the cell cycle

o  ‘Gap 1’ is the longest stage in the cell cycle

o  Stomach lining cells divide at the highest rate

o  A cell’s ratio of surface area to volume limits its size

o  Neurons undergo mitosis least often

·  Section 5.2 Quiz:

o  A ‘telomere’ is a structure that protects the ends of chromosomes

o  A chromatin is a loose organization of DNA and proteins

o  DNA is organized in a cell by wrapping it around histones (proteins) at regular intervals

o  Metaphase is the stage of mitosis in which spindle fibers attach to chromosomes (and align the chromosomes along the middle of the cell)

o  Daughter cells have the same number of chromosomes as the original cell

·  Section 5.3 Quiz:

o  When an oncogene mutates, the cell cycle speeds up (eventually resulting in cancer)

o  Growth factors are proteins that stimulate cell division

o  Apoptosis is programmed cell death

o  Benign and malignant tumors are different in that benign tumors do not spread, while malignant tumors fragment and may spread to other parts of the body

o  Treatments for cancer include radiation therapy, surgery, and chemotherapy, but not ‘HeLa cells’

·  Section 5.4 Quiz:

o  Most prokaryotes reproduce through binary fission

o  Mitosis differs from binary fission in that mitosis is the division of a cell’s nucleus

o  Asexual reproduction may be an advantage to an organism that lives in a small, widely scattered population in that the organism would not have to spend time an energy to find a mate

o  Sexual reproduction involves gametes (sex cells)

o  Starfish fragments growing into whole new starfish is an example of the reproductive process of fragmentation

·  Section 5.5 Quiz:

o  Bones, muscles, and kidneys form from the middle layer of a vertebrate embryo

o  The following are arranged from smallest to largest: cell – tissue – organ – organ system

o  A cell in an embryo will differentiate based on its location within the embryo

o  Totipotent stem cells can grow into any cell type in the body

o  Stem cells cannot turn into any cell type after becoming specialized

Jack Bowers

1.8.2009

Biology Chapter 6 Notes

Ø  Vocabulary/Other

·  Mitosis: Replication of somatic diploid cells.

o  Creates two diploid cells from one diploid cell.

o  Chromosomes stay in pairs.

o  Continues until death.

·  Meiosis: Splitting of diploid cells to create gametes.

o  Produces four sperm in the male, and one egg in the female.

o  Chromosomes are split up among resulting gametes.

·  Gametogenesis: Process by which gametes are produced through the combination of meiosis and other maturational changes

·  Polar Body: Haploid cell produced during meiosis. Is in the female of many species; these cells have little more than DNA and eventually disintegrate.

·  Body Cells:

o  Also known as somatic cells

o  Are diploid (have two copies of each chromosome,) and have a total of 46 chromosomes arranged in 23 pairs

o  Have 44 autosomes and 2 sex chromosomes

·  Sex Cells:

o  Also known as gametes

o  Are haploid (have one copy of each chromosome,) have a total of 23 single chromosomes

o  Types:

§  Sperm: Comes from male. Provides DNA for the offspring

§  Egg: Comes from female. Provides DNA, organelles, molecular building blocks, and materials for the offspring

·  Autosomes: Chromosomes that contain genes for characteristics not directly related to the sex of the organism

·  Sex Chromosomes: Sex chromosomes (determine gender in animals: XY = Male, XX = Female)

·  Sexual Reproduction: Process by which two gametes fuse and offspring that are a genetic mixture of both parents are produced

·  Fertilization: Fusion of an egg and sperm cell

·  Mendel: Scientist who studied pea plants and provided the basis of modern genetics

·  Homologous chromosomes: Chromosomes that have the same length, appearance, and copies of genes, although the alleles may differ

·  Crossing Over: Exchange of chromosome segments between homologous chromosomes during meiosis I.

·  Cross: Mating of two organisms

·  Monohybrid Cross: Cross, or mating, between organisms that involves only one pair of contrasting traits

·  Dihybrid Cross: Cross, or mating, between organisms involving two pairs of contrasting traits.

·  Test cross: Cross between an organism with an unknown genotype and an organism with a recessive phenotype

·  Gene: Specific region of DNA that codes for a particular protein

·  Genetics: Study of the heredity patterns and variation of organisms

·  Genetic linkage: Tendency for genes located close together on the same chromosome to be inherited together

·  Genome: All of an organism’s genetic material

·  Genotype: Collection of all an organism’s genetic information that codes for traits

·  Phenotype: Collection of all an organism’s physical characteristics

·  Punnett Square: Model for predicting all possible genotypes resulting from a cross, or mating

·  Heterozygous: Characteristic of having two different alleles that appear at the same locus of sister chromatids.

·  Trait: Characteristic that is inherited

·  Allele: Any of the alternative forms of a gene that occurs on a specific place on a chromosome