Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
144 Cards in this Set
- Front
- Back
|
The Goal of Science
|
investigate and understand the natural world, to explain events in the natural world, and to use those explanations to make useful predictions.
|
|
|
Science
|
organized way of using evidence to learn about the natural world; also, the body of knowledge that scientists have built up after years of using this process
|
|
|
Observation
|
use of one or more of the senses—sight, hearing, touch, smell, and sometimes taste—to gather information
|
|
|
Hypothesis
|
possible explanation for a set of observations or possible answer to a scientific question
|
|
|
Controlled Experiment
|
a test of the effect of a single variable by changing it while keeping all other variables the same
|
|
|
Theory
|
well-tested explanation that unifies a broad range of observations
|
|
|
Characteristics of Living Things
|
made up of cells; reproduce; based on universal genetic code; grow and develop; obtain and use material and energy; respond to environment; stable internal environment; change over time as a group
|
|
|
Metabolism
|
set of chemical reactions through which an organism builds up or breaks down materials as it carries out its life processes
|
|
|
Stimulus
|
a signal to which an organism responds
|
|
|
Homeostasis
|
process by which organisms maintain a relatively stable internal environment
|
|
|
Evolution
|
change in a kind of organism over time; process by which modern organisms have descended from ancient organisms
|
|
|
Levels of Organization
|
Molecules, cells, group of cells, organisms, population, community, ecosystem, biosphere
|
|
|
Atom
|
basic unit of matter
|
|
|
Isotope
|
atom of an element that has a number of neutrons different from that of other atoms of the same element; Because they have the same number of electrons, all isotopes of an element have the same chemical properties
|
|
|
Ionic Bond
|
bond formed when one or more electrons are transferred from one atom to another
|
|
|
Ion
|
atom that has a positive or negative charge
|
|
|
Covalent Bond
|
bond formed by the sharing of electrons between atoms
|
|
|
Molecule
|
smallest unit of most compounds
|
|
|
van der Waals forces
|
a slight attraction that develops between the oppositely charged regions of nearby molecules
|
|
|
Why water is polar
|
A water molecule is polar because there is an uneven distribution of electrons between the oxygen and hydrogen atoms
|
|
|
Cohesion
|
attraction between molecules of the same substance
|
|
|
Adhesion
|
attraction between molecules of different substances; in plants, attraction between unlike molecules
|
|
|
Capillary Action
|
one of the forces that draw water out of the roots of a plant and up into its stems and leaves
|
|
|
pH scale
|
measurement system used to indicate the concentration of hydrogen ions (H+) in solution; ranges from 0 to 14
|
|
|
Acidic Solutions
|
contain higher concentrations of H+ ions than pure water and have pH values below 7
|
|
|
Acid
|
compound that forms hydrogen ions (H+) in solution
|
|
|
Base
|
compound that produces hydroxide ions (OH+) in solution
|
|
|
Basic Solutions
|
alkaline, solutions contain lower concentrations of H+ ions than pure water and have pH values above 7
|
|
|
Buffer
|
weak acid or base that can react with strong acids or bases to help prevent sharp, sudden changes in pH
|
|
|
Four groups of organic compounds found in living things
|
carbohydrates, lipids, nucleic acids, and proteins
|
|
|
Carbohydrate
|
compound made up of carbon, hydrogen, and oxygen atoms; major source of energy for the human body
|
|
|
monosaccharide
|
single sugar molecule
|
|
|
polysaccharide
|
large macromolecule formed from monosaccharides
|
|
|
Lipids
|
macromolecule made mainly from carbon and hydrogen atoms; includes fats, oils, and waxes
can be used to store energy |
|
|
Building block of lipids
|
fatty acids
|
|
|
Nucleic Acid
|
macromolecule containing hydrogen, oxygen, nitrogen, carbon, and phosphorus
|
|
|
Nucleotide
|
monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base
|
|
|
ribonucleic acid (RNA)
|
single-stranded nucleic acid that contains the sugar ribose
|
|
|
deoxyribonucleic acid (DNA)
|
nucleic acid that contains the sugar deoxyribose
|
|
|
Protein
|
macromolecule that contains carbon, hydrogen, oxygen, and nitrogen; needed by the body for growth and repair and to make up enzymes
|
|
|
Amino Acid
|
compound with an amino group (−NH2) on one end and a carboxyl group (−COOH) on the other end, building blocks of protein
|
|
|
Chemical Reactions
|
always involve the breaking of bonds in reactants and the formation of new bonds in products.
|
|
|
Energy in Reactions
|
Chemical reactions that release energy often occur spontaneously. Chemical reactions that absorb energy will not occur without a source of energy.
|
|
|
Activation Energy
|
energy needed to get a reaction started
|
|
|
Catalyst
|
substance that speeds up the rate of a chemical reaction
|
|
|
enzyme
|
protein that acts as a biological catalyst
speed up chemical reactions that take place in cells |
|
|
Substrate
|
reactant of an enzyme-catalyzed reaction
|
|
|
Cell Theory
|
idea that all living things are composed of cells, cells are the basic units of structure and function in living things, and new cells are produced from existing cells
|
|
|
electron microscopes
|
capable of revealing details as much as 1000 times smaller than those visible in light microscopes because the wavelengths of electrons are much shorter than those of light
|
|
|
Transmission electron microscopes (TEMs)
|
make it possible to explore cell structures and large protein molecules.
|
|
|
scanning electron microscopes (SEMs)
|
pencillike beam of electrons is scanned over the surface of a specimen produces stunning three-dimensional images of cells
|
|
|
scanning probe microscopes
|
produce images by tracing the surfaces of samples with a fine probe
|
|
|
Cytoplasm
|
material inside the cell membrane—not including the nucleus
|
|
|
Nuclear Envelope
|
layer of two membranes that surrounds the nucleus of a cell
|
|
|
Chromatin
|
granular material visible within the nucleus; consists of DNA tightly coiled around proteins
|
|
|
Chromosome
|
threadlike structure within the nucleus containing the genetic information that is passed from one generation of cells to the next
|
|
|
Ribsome
|
small particle in the cell on which proteins are assembled; made of RNA and protein
|
|
|
Endoplasmic Reticulum
|
internal membrane system in cells in which lipid components of the cell membrane are assembled and some proteins are modified
|
|
|
Golgi Apparatus
|
stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum
|
|
|
Lysosome
|
cell organelle filled with enzymes needed to break down certain materials in the cell
|
|
|
Vacuole
|
cell organelle that stores materials such as water, salts, proteins, and carbohydrates
|
|
|
Mitochondria
|
cell organelle that converts the chemical energy stored in food into compounds that are more convenient for the cell to use
|
|
|
Chloroplasts
|
organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy
|
|
|
Cytoskeleton
|
network of protein filaments within some cells that helps the cell maintain its shape and is involved in many forms of cell movement
|
|
|
Centrioles
|
one of two tiny structures located in the cytoplasm of animal cells near the nuclear envelope
|
|
|
Lipid Bilayer
|
double-layered sheet that forms the core of nearly all cell membranes
|
|
|
Diffusion
|
process by which molecules tend to move from an area where they are more concentrated to an area where they are less concentrated
|
|
|
Equillibrium
|
when the concentration of a solute is the same throughout a solution
|
|
|
Osmosis
|
diffusion of water through a selectively permeable membrane
|
|
|
Isotonic
|
when the concentration of two solutions is the same
|
|
|
Hypertonic
|
when comparing two solutions, the solution with the greater concentration of solutes
|
|
|
Hypotonic
|
when comparing two solutions, the solution with the lesser concentration of solutes
|
|
|
Facilitated Diffusion
|
movement of specific molecules across cell membranes through protein channels
|
|
|
Active Transport
|
energy-requiring process that moves material across a cell membrane against a concentration difference
|
|
|
endocytosis
|
process by which a cell takes material into the cell by infolding of the cell membrane
|
|
|
phagocytosis
|
process in which extensions of cytoplasm surround and engulf large particles and take them into the cell
|
|
|
pinocytosis
|
process by which a cell takes in liquid from the surrounding environment
|
|
|
exocytosis
|
process by which a cell releases large amounts of material
|
|
|
Cell Specialization
|
the process in which cells develop in different ways to perform different tasks
|
|
|
Tissue
|
group of similar cells that perform a particular function
|
|
|
Organ
|
group of tissues that work together to perform closely related functions
|
|
|
Organ System
|
group of organs that work together to perform a specific function
|
|
|
Autotrophs
|
organism that can capture energy from sunlight or chemicals and use it to produce its own food from inorganic compounds; also called a producer
|
|
|
Heterotrophs
|
organism that obtains energy from the foods it consumes; also called a consumer
|
|
|
adenosine triphosphate (ATP) |
one of the principal chemical compounds that living things use to store and release energy; Energy is released when the bonds that hold the phosphate groups together are broken
Provides immediate energy for the cell. The removal of a phosphate group from ATP produces adenosine diphosphate or ADP |
|
|
Photosynthesis
|
process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars and starches
|
|
|
Helmont, Priestley, and Ingenhousz Experiments
|
discovered that in the presence of light, plants transform carbon dioxide and water into carbohydrates, and they also release oxygen
|
|
|
Photosynthesis Chemical Equation
|
Carbon dioxide + water -glucose + oxygen + energy
or 6CO2 + 6H2O C6H12O6 + 6O2 |
|
|
Pigment
|
light-absorbing molecule
|
|
|
chlorophyll
|
principal pigment of plants and other photosynthetic organisms; captures light energy
|
|
|
Thylakoid
|
saclike photosynthetic membrane found in chloroplasts
|
|
|
Photosystems
|
light-collecting units of the chloroplast; located in thylakoid membrane
|
|
|
Stroma
|
region outside the thylakoid membranes in chloroplasts, where the Calvin Cycle takes place
|
|
|
NADP+ (nicotinamide adenine dinucleotide phosphate)
|
one of the carrier molecules that transfers high-energy electrons from chlorophyll to other molecules
|
|
|
Light-Dependent Reactions
|
produce oxygen gas and convert ADP and NADP+ into the energy carriers ATP and NADPH; takes place in the thylakoid membrane
|
|
|
ATP synthase
|
large protein that uses energy from H+ ions to bind ADP and a phosphate group together to produce ATP
|
|
|
Calvin Cycle
|
reactions of photosynthesis in which energy from ATP and NADPH is used to build high-energy compounds such as sugars; takes place in the stroma
|
|
|
Factors Affecting Photosynthesis
|
amount of water, temperature, and light intensity
|
|
|
Calorie
|
amount of energy needed to raise the temperature of 1 gram of water 1 degree Celsius
|
|
|
Glycolysis
|
first step in releasing the energy of glucose, in which a molecule of glucose is broken into two molecules of pyruvic acid
|
|
|
Cellular Respiration
|
process that releases energy by breaking down glucose and other food molecules in the presence of oxygen
|
|
|
NAD+ (nicotinamide adenine dinucleotide)
|
electron carrier involved in glycolysis
|
|
|
Fermentation
|
process by which cells release energy in the absence of oxygen
|
|
|
Anaerobic
|
process that does not require oxygen
|
|
|
2 Types of Fermentaion
|
Alcoholic Fermentation and Lactic Acid Fermentation
|
|
|
Aerobic
|
process that requires oxygen
|
|
|
Krebs Cycle
|
second stage of cellular respiration, in which pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions
|
|
|
Electron Chain Transport
|
a series of proteins in which the high-energy electrons from the Krebs cycle are used to convert ADP into ATP
|
|
|
Chromatid
|
one of two identical “sister” parts of a duplicated chromosome
|
|
|
Centromere
|
area where the chromatids of a chromosome are attached
|
|
|
Interphase
|
period of the cell cycle between cell divisions
|
|
|
Cell Cycle
|
series of events that cells go through as they grow and divide
|
|
|
Prophase
|
first and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus
|
|
|
Spindle
|
fanlike microtubule structure that helps separate the chromosomes during mitosis
|
|
|
Metaphase
|
second phase of mitosis, during which the chromosomes line up across the center of the cell
|
|
|
Anaphase
|
the third phase of mitosis, during which the chromosome pairs separate and move toward opposite poles
|
|
|
Telophase
|
fourth and final phase of mitosis, during which the chromosomes begin to disperse into a tangle of dense material
|
|
|
Cyclin
|
one of a family of closely related proteins that regulate the cell cycle in eukaryotic cells
|
|
|
Cancer
|
disorder in which some of the body's own cells lose the ability to control growth
|
|
|
Homologous
|
term used to refer to chromosomes that each have a corresponding chromosome from the opposite-sex parent
|
|
|
Meiosis
|
process by which the number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell
|
|
|
Diploid
|
term used to refer to a cell that contains both sets of homologous chromosomes
|
|
|
Haploid
|
term used to refer to a cell that contains only a single set of chromosomes and therefore only a single set of genes
|
|
|
Transformation
|
process in which one strain of bacteria is changed by a gene or genes from another strain of bacteria
|
|
|
bacteriophage
|
virus that infects bacteria
|
|
|
Base Pairing
|
principle that bonds in DNA can form only between adenine and thymine and between guanine and cytosine
|
|
|
Atomic Number
|
Number of protons/electrons
|
|
|
Atomic Mass
|
Protons + Neutrons
|
|
|
Hydrogen Bonds
|
Between oxygen and hydrogen or oxugen and nitrogen
|
|
|
Phospholipids
|
one of the fatty acid is replaced with phosphate which causes it to have a polar head in the
phospholipids bilayer |
|
|
Richard Hooke
|
called the cells of a slice of cord "cells" because they reminded him of tiny rooms
|
|
|
Melvin Calvin
|
Discovered the Kelvin Cycle
|
|
|
The four nitrogenous bases in DNA
|
Adenine Thymine Guanine Cytosine
|
|
|
The four nitrogenous bases in RNA
|
Adenine, Guanine, Cytosine, Uracil
|
|
|
The Hydrogen Bonds of DNA
|
A--T; G---C
|
|
|
DNA polymerase
|
enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule
|
|
|
NADPH
|
electron carrier in photosynthesis
|
|
|
carotenoids
|
• The pigments that produce yellow and orange fall leaf colors, as well as the colors of many fruits, vegetables, and flowers
|
|
|
Totals
|
Glycolysis: 4 ATP (net gain 2)
Cellualar Resp. : 36 ATP, 18 each turn of the cycle |
|
|
Equation for Lactic Acid Fermentation
|
pyruvic acid + NADH ➝ lactic acid + NAD+
|
|
|
Equation for Alchoholic Fermentation
|
pyruvic acid + NADH ➝ alcohol + CO2 + NAD+.
|
|
|
acetyl-CoA
|
made from two carbon atoms from pyruvic acid are joined to a compound called coenzyme A; starts the Krebs cycle
|
|
|
Electron acceptors in Cellular Resp.
|
NAD+ and FAD
|
|
|
electron carriers in Cellular Resp.
|
NADH and FADH2
|
