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Biology
Question | Answer |
---|---|
Cancer causing substances | Carcinogen |
All the DNA in one cell of an organism | Genome |
Members of the protista kingdom have these but the monera kingdom do not | cell nucleus |
Eustachian Tube is found in this part of the body | the ear |
What part of your body would you find the rectus abdominis muscle? | Abdomen |
What part of your body would you find the gluteus medius? | Hip/Buttocks |
A plant leaning toward the light from a sunny window is an example of what process | Phototropism |
Bodily system responsible for transporting, breaking down and absorbing good. Accessory organs include the pancreas and gall bladder | Digestive System (accept gastrointestinal system) |
Process of programmed cell death | Apoptosis |
Austrian monk conducted experiments on the inheritance of traits in pea plants | Gregor Mendel |
Co-founder of the Journal of Genetics. Better known for his square, in which one parent's genotype is assigned to a grid's row and the other parent's genotype to the columbs | Reginald Punnett (Punnett square) |
Genetic makeup of an organism or group of organisms with reference to a single trait, set of traits, or an entire complex of traits. | Genotype |
DNA stands for | deoxyribonucleic acid |
RNA stands for | Ribonucleic acid |
It was the first mass-produced antibiotic and discovered by Alexander Fleming | Penicillin |
Resistance to antibiotics is often spread between bacteria via these small, circular pieces of non-chromosomal DNA | plasmids |
Roughly 96 percent of the mass of the human body is made up of these four elements | oxygen, carbon, hydrogen and nitrogen |
Class of nitrogenous organic compounds that consist of large molecules composed of long chains of amino acids. Essential part of all living organisms, especially as structural components of body tissues such as muscle, hair, collagen, enzymes & antibodies | Protein |
A large group of organic compounds occurring in foods and living tissues and including sugars, starch, and cellulose. They contain hydrogen and oxygen in the same ratio as water (2:1) and typically can be broken down to release energy in the animal body. | Carbohydrates |
Nonliving; specifically, the nonliving components of an ecosystem, such as temperature, humidity, the mineral content of the soil, etc. | Abiotic |
A nucleotide consisting of adenine, ribose, and two phosphate groups; formed by the removal of one phosphate from an ATP molecule. | adenosine diphosphate (ADP) |
An adenine-containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolyzed. This energy is used to drive endergonic reactions in cells. | adenosine triphosphate (ATP) |
Containing oxygen; referring to an organism, environment, or cellular process that requires oxygen. | aerobic |
An alternative form of a gene. One of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome. | allele |
A chemical that kills bacteria or inhibits their growth | antibiotic |
The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits. | artificial selection |
A four-stage process that creates two identical cells from one original cell. | Mitosis |
The first and longest stage of mitosis. In this stage the chromosomes become visible and the centrioles separate and move to opposite poles of the cell. | Prophase |
The second stage of mitosis. In this stage the chromosomes line up across the center of the cell and become connected to the spindle fiber at their centromere. | Metaphase |
The third stage of mitosis. In this stage the sister chromatids separate into individual chromosomes and are pulled apart. | Anaphase |
The fourth and last stage of mitosis. During this stage the chromosomes gather at opposite ends of the cell & lose their distinct rod-like shapes. Two new nuclear membranes then form around each of the two regions of DNA and the spindle fibers disappear. | Telophase |
With 2 complete copies of the DNA now in 2 different regions of one cell, the cell membrane will pinch & divide the cytoplasm in half. The result is 2 individual cells that are identical to the original. | Cytokinesis. (The process that follows the last stage of mitosis. Each of the 2 new cells have a complete copy of the DNA and contain all of the organelles that the original cell had.) |
A period of cell growth and normal activity. This period comes between mitosis in the cell cycle. Cells that do not need to replicate will spend their time in this stage. | Interphase (If a cell does need to divide, it will copy all of it's DNA. This way, the cell has two complete copies of its DNA before it begins the process of mitosis.) |
The chromosomes condense, and the nuclear envelope breaks down. crossing-over occurs. | Prophase I |
Pairs of homologous chromosomes move to the equator of the cell | Metaphase I |
Homologous chromosomes move to the opposite poles of the cell. | Anaphase I |
Chromosomes gather at the poles of the cells. the cytoplasm divides. | Telophase I and Cytokinesis |
A new spindle forms around the chromosomes. | Prophase II |
Chromosomes line up at the equator. | Metaphase II |
Centromeres divides. chromatids move to the opposite poles of the cells. | Anaphase II |
A nuclear envelope forms around each set of chromosomes. the cytoplasm divides. | Telophase II and Cytokinesis |
Backed up by hundreds of thousands of data observations by independent scientists, all of whom have come to the same conclusion. | Theory |
Created theory of evolution | Charles Darwin |
using any of your senses to describe a phenomena | Observation |
the process of deriving the strict logical consequences of assumed premises . | Inference |
a testable and falsifiable explanation of an observation. | Hypothesis |
the worldwide geographical distribution of species. | Biogeography |
structural and functional similarities that contribute to the identification of evolutionary relationships among species. | Homologous Structures |
show conservation of homeotic genes. | Embryological Structures |
include genes, proteins, and protein products, shared among organisms inherited from a common ancestor. | Molecular Homologies |
a trait, structure, function, or behavior that gives the organism an evolutionary advantage. | adaptation |
the expressed or physical trait of an organism. | phenotype |
the actual genetic makeup that results in an expressed phenotype | genotype |
the actual frequency of each type of gene in a population. | gene pool |
brand new genes that randomly occur. | mutation |
movement from one population to another introduces new alleles and genes | gene flows |
a natural disaster causes a population or a particular part of a population to be wiped out. | bottleneck effect |
a small group in a population splinters off the original and forms a new one. | founder effect |
The study of interactions among and between organisms and their environment. | Ecology |
No organism can survive without help from other organisms. Example - Plants and Soil | Interdependence |
A group of organisms that have similar traits and can produce viable offspring through reproduction. | Species |
All the members of a species that live in a specific geographical area. | Population |
The grouping of two or more populations of species that live in and interact with each other in a specific geographical area. This includes all organisms: plants, animals, fungi, etc. | Community |
The interaction between the biotic (living) community and the abiotic (non-living) environment. | Ecosystem |
This is all of the ecosystems within a specific climate zone. These are large areas that have similar weather patterns, temperature, and moisture levels. Examples: tropical forest, deciduous forest, grasslands, and deserts. | Biome |
All parts of the Earth that support life. | Biosphere |
An organism that can make organic molecules needed for survival from inorganic sources. This is achieved through photosynthesis (light energy) or chemosynthesis (chemical energy). | Autotroph |
Always the lowest on the chain or pyramid and largest group in any ecosystem. | Producers |
Organisms that cannot produce their own organic energy molecules from inorganic sources, hence, they feed on other organisms to gain energy. | Heterotroph |
Only eat plants. Flat teeth for grinding. Digestive track designed to help with the breakdown of grasses and plant matter. | Herbivore (ex: Cows, Deer) |
Only eat other animals (meat). Sharp teeth for tearing and ripping | Carnivore (ex: wolves, lions) |
Eat both plants and animals. Have both grinding and tearing teeth | Omnivore (ex: humans, bears) |
The breakdown of dead organic matter back into the original elements. | Decomposition |
These organisms do the mechanical breakdown of dead plant and animal matter. They feed on the dead organisms for energy. Also known as scavengers. These organisms make a byproduct called detritus. | Detritivore |
These organisms are responsible for the chemical breakdown back into the original chemical components. They breakdown the detritus left behind by the detritivores. | Decomposer (Examples: bacteria, fungi) |
Capture and convert light energy from the sun into usable chemical energy. Plants like algae, grasses, and trees use this | Photosynthesis |
Captures the energy that is released when chemical bonds are broken. No light is needed and most the time light is not present at all. Organisms like sulfur bacteria, white smokers, and black smokers usethis. | Chemosynthesis |
A simple linear series of steps that show how energy moves from one organism to another. | Food Chain |
Always starts with a producer and will end with an animal that is not directly threatened by any other animal. Example: Grass → Rabbit → Coyote | Food Chain |
A complex connection of all the food chains within an ecosystem. | Food Web |
Move through the ecosystem through biochemical cycles. •Carbon cycle, water cycle, etc. •Constantly being recycled but never being lost. | Nutrients |
Moves from one organism to another and along the way some of it is lost in the form of heat. • It is NOT recycled. •Remember the 10% rule of Food chains and its' pyramid. | Energy |
Any relationship in which two species live closely together. “living together” | Symbiosis (symbiotic relationship) |
Organisms of the same or different species attempt to occupy the same niche within the same geographical area at the same time. | Competition |
A role that an organism plays within its ecosystem Includes: shelter, food, etc. | Niche |
Anything necessary for life. If they are scarce competition will increase as the availability of them decrease and the diversity of niches narrow. | Resources |
Both species will benefit from the relationship. Example: Bees and Flowers | Mutualism |
One Member of the association benefits and one is neither helped nor harmed. Example: Barnacles and Whales | Commensalism |
Interaction in which one organism captures and feeds on another organism. | Predation |
The organism that hunts and kills and other organism. Characteristics: Sharp teeth, great hearing, great sight, etc. | Predator |
The organism that is eaten by the predator. Characteristics: Large numbers, since of community, great hiding, etc. | Prey |
The ability to blend into your surroundings. These organisms will sit very still to help with avoid detection. | Camouflage |
he use of coloration to represent something that is dangerous/ poisonous. | Mimicry |
Spikes, thick skin, poisonous skin are examples of | Protective appendages |
one organism lives on or inside another organism and harms it | Parasitism |
the organism that is living off the other organism. They can spread infectious disease. | parasite |
the organism that is being harmed | Host |
Ticks are example of this type of parasite; they live on the outside of the host and suck their blood | External Parasite |
Tapeworms are example of this type of parasite. They live in the digestive track & doesn't cause the host to show symptoms until they are large enough to steal a majority of the nutrients from the host. | Internal Parasite |
The movement of individuals into an area | Immigration |
The movement of individuals out of an area. | Emigration |
What three things affects population size? | Number of births, Number of deaths, Number of individuals leaving or entering the population (applies to natural populations) |
The largest number of individuals that a particular area can support. Dependent on the amount of available resources. Numbers vary depending on the species and their size and niche. Can be influenced by season, disease, and other factors | Carrying Capacity |
Number of individuals per unit area. | Population Density |
something that can cause the population to stop growing | Limiting Factor |
Will affect the population no matter what the size or density •Natural disasters •Seasonal cycles •Disturbances caused by humans •Forestry •Pollution | Density-Independent Factors |
depend on population size •Competition •Predation •Disease •Parasitism | Density-Dependent Factors |
The series of changes that occur in an ecosystem over time. | Succession |
Occurs where there is NO soil •Bedrock left by a glacier retreating •Lava covered area •Lichens= a combination of a fungi and alga •Breakdown the rock surface into a soil and by decomposition of dead lichens | Primary Succession |
Process by which an ecosystem returns to its original state after a disturbance. •Organisms start growing in order of size and nutritional needs. | Secondary Succession |
the aqueous (water-based) environment of the cell. | Cytoplasm |
Specialized structures found within the cell. They are often referred to as “little organs” of the cell. | Organelles |
Only _____________ cells have a nucleus | Eukaryotic |
often referred to as the “brain of the cell”, it can also be considered as the “control center”. | Nucleus |
The ___________________ directs protein synthesis | Nucleus |
The Nucleus contains the _________________ (genetic material). | DNA (deoxyribonucleic acid) |
The nucleus is surrounded by the __________________ ______________________. This regulates what comes in and out of the nucleus. Also keeps the DNA inside the nucleus. | nuclear membrane |
small dense region within the nucleus where the assembly of ribosomes begins. | Nucleous |
the "Powerhouse” of the cell. | Mitochondrion |
They convert chemical energy stored in food to usable energy in the form of ATP that can be used by the cell | Mitochondrion |
_________________________ are the site of cellular respiration | Mitochondria |
Cells will take glucose and oxygen and use them to make energy, letting off carbon dioxide and water | Cellular Respiration |
The mitochondria is a double membraned organelle that arose from _______________________________ | endosymbiosis |
The folds of the inner membrane system inside the mitochondria. These help efficiency by increasing surface area. | Cristae |
Considered the “Protein factory” of the cell. They are particles that produce proteins following the instructions of the nucleus. | Ribosomes |
Cells that are active in protein synthesis are packed with ____________________________. (Example: muscle cells) They can be free floating in the cytoplasm or attached to the rough endoplasmic reticulum. | ribosomes |
All living things are composed of _________________, from single celled bacteria to multi-cellular organisms like humans. | cells |
the basic unit of structure and function in living things. | cells |
New cells are produced from existing cells through ________ _______________________ | cell division. |
These cells do not have a nucleus and are generally simpler than eukaryotic cells. | Prokaryote |
These cells do have a nucleus and are usually larger and are more complex than prokaryotic cells. Specialized to preform specific tasks. | Eukaryote |
The inner membrane system of the cell consisting of two types. | Endoplasmic Reticulum (ER) |
Involved in Protein Synthesis. Contains Ribosomes | Rough Endoplasmic Reticulum (Rough ER) |
Contains Digestive Enzymes. Involved in Lipid Synthesis and Detoxification of Drugs | Smooth Endoplasmic Reticulum (Smooth ER) |
“Shipping Company of the Cell” Puts finishing touches on packages and ships them to where they need to go. | Golgi Apparatus (body or complex) |
Used for storage of: ◦water, salts, excess proteins, and carbohydrates Animal cells: Small. Plant cells: Have a large central one for water storage | Vacuoles |
ONLY IN PHOTOSYNTHETIC ORGANISMS. EX: Plants, and some bacteria and protists. They are found in the green parts of the plant. Usually the leaves | Chloroplasts |
Chloroplast 4 parts are | Outer membrane, Thylakoids, Grana, Stroma |
the green light absorbing pigment in the chloroplasts | Chlorophyll |
Light is required. Conversion of solar energy into sugar(glucose). Releases oxygen as a by-product (waste) | Photosynthesis |
Two stages of Photosynthesis | Light Dependent Reactions, "Dark Reactions" light independent reactions |
Light collection reaction in photosynthesis | Light Dependent Reaction |
Reaction that involves the creation of sugars. This happens all the time not only at night when it is dark. | "Dark Reactions" light independent reactions |
Part of the phospholipid bilayer. It is the non-polar region that does not like to be in water | Hydrophobic Tail |
Part of the phospholipid bilayer. It is the polar region that is attracted to the water-based environment both inside and outside of the cell | Hydrophilic Head |
They orientate themselves so that the tails face into each other creating an area with no water and the heads face out, toward the surrounding environment and into the cell | Phospholipids |
Structure and stability of the cell. Regulates what goes into and out of the cell. •Selective permeability: “able to pass through” | Cell Membrane |
Proteins embedded in the membrane, which allows larger molecules through the membrane into and out of the cell. These are used during facilitated diffusion. | Protein Channel |
Carbohydrates that are embedded in the outer portion of the membrane that allow signaling between the cell and its environment and other cells using hormones. | Carbohydrate Channels |
Found in plant, algae, and fungi. NOT in animal cell. Provides support and protection for the cell. (rigid unlike the cell membrane) | Cell Wall |
Cell Wall is composed mainly of _____________________ | cellulose |
Water moves toward the area of highest ___________ concentration. | solute |
The solute concentration inside and outside the cell are equal. The cell and the environment are in a state of equilibrium the cell will maintain its size. | isotonic |
The solute concentration is higher outside of the cell. (there is MORE solute outside) •Water moves out of the cell and the cell will shrink. | hypertonic |
The solute concentration outside the cell is lower than inside the cell. (there is LESS solute outside) •Water moves into the cell and the cell will swell/burst (lysis). | hypotonic |
Diffusion of water through a selectively permeable membrane ◦Movement from an area of high concentration to an area of low concentration. | osmosis |
Process by which molecules move from areas of high concentration to areas of low concentration. This does NOT require energy | diffusion Examples: Food coloring in the beaker or water. Air freshener in a room |
Mass of the solute in a given volume of solution or mass/volume. Expressed as g/L or equivalent | concentration |
NO energy is required. Movement along the concentration gradient. (high to low) | Passive Transport |
Movement of particles across the selectively permeable membrane. Occurs in passive transport | Simple Diffusion |
Moving from high to low Moving through protein channels in the cell membrane which allow certain molecules across the membrane (large and charged molecules) | Facilitated Diffusion Example: Glucose moving in and out of red blood cells using a channel |
Energy IS required •Movement against the concentration gradient. (low to high). Movement has to go through a protein channel/pump. | Active Transport Examples: ◦Cellular respiration with the movement of hydrogen ions to make ATP ◦The sodium potassium pump |
The process taking material into the cell. Two types: Phagocytosis & Pinocytosis | Endocytosis |
Means “cell eating” The cytoplasm will extend around a particle and packages it within food vacuoles. Used by single-celled organisms like an ameba. | Phagocytosis |
Process used by cells to take up liquid from the environment. Pockets fill along the membrane and then pinch off to form vacuoles. | Pinocytosis |
The process of pushing material out of the cell. | Exocytosis |
The conversion of solar energy to a usable chemical energy. | photosynthesis |
Scientist who used mass experiment to determine that plants get their mass from water | Jan van Helmont |
Scientist who discovered that plants only produce oxygen in the presence of light. | Jan Ingenhousz |
Scientist who discovered that plants produce oxygen as they grow. He used a mint leaf inside of a jar. | Joseph Priestley |
Reactants involved in photosynthesis | Carbon dioxide and water |
Products involved in photosynthesis | Sugar (glucose), Atmospheric Oxygen (O2) |
C6H12O6 is the chemical formula for | Glucose |
3 factors that affect the rate of photosynthesis: | Water, Temperature, Light Density |
The process that releases energy by breaking down glucose and other food molecules in the presence of oxygen. •Takes place in the mitochondria. | Cellular Respiration |
This is the opposite of photosynthesis | Cellular Respiration |
This is the chemical equation for what? 6CO2 + 6H2O ->C6H12O6 + 6O2 | Photosynthesis |
This is the chemical equation for what? C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP | Cellular Respiration |
Glucose + Oxygen -> Carbon Dioxide + Water | Cellular Respiration |
Carbon Dioxide + Water -> Glucose + Oxygen | Photosynthesis |
One of the principal chemical compounds that cells use to store and release energy. (The energy currency of the cell.) | ATP (Adenosine triphosphate ) |
What chemical compound is this: 1 adenine molecule ◦1 ribose (5-carbon sugar) ◦3 phosphate groups | ATP (Adenosine triphosphate ) |
The third phosphate group is the key to releasing and storing energy. If it is attached, energy is stored in the bonds. When energy is needed, the bonds are broken energy is released. | ATP (Adenosine triphosphate ) |
This is the uncharged form. The third phosphate has been broken off. | ADP (Adenosine diphosphate) |
1 adenine molecule ◦1 ribose (5-carbon sugar) ◦2 phosphate groups | ADP (Adenosine diphosphate) |
Light absorbing molecules. Chlorophyll is the principal ____________________ of photosynthesis. | pigment |
Plants do not absorb much if any ______________ _______________so that is why plants are green. | green light |
The cell becomes too large for the DNA to handle. ◦There is only enough DNA to regulate a cell of a certain size. | DNA overload |
Food & water enter a cell and waste products leave through the cell membrane. This rate of exchange is dependent on the cell’s surface area to volume ratio. As something becomes bigger the surface area of the cell gets smaller in respect to the size. | Exchange rate of materials: |
Two reasons for cell divison | DNA overload, Exchange Rate of Materials |
when the cells of the body no longer respond to the signals that regulate the cell cycle. ◦Uncontrollable cell division | Cancer |
A mass of defective cells. Damaging to the organisms because they affect the function of the tissues and organs. | Tumors |
Referred to as reduction division. ◦This division results in 4 haploid cells. ◦These cells are used in sexual reproduction and are called gametes. | Meiosis |
While homologous chromosomes are paired up they exchange portions of their DNA. ◦This creates genetic variation within a population. | Crossing Over |
Chromosomes that code for the same things but one is from mom and one is from dad. A pair of these chromosomes make a tetrad. ◾Contains 4 chromatids | Homologous Chromosomes |
Cuts the number of chromosomes in half by separating homologous chromosomes in a diploid cell. | Meiosis |
Means “two set” referring to the number of chromosomes. ◦One set from mom one from dad = 2 sets •“Somatic” or body cells •Produced by the process of mitosis •Represented by the symbol 2N •In humans this number is 46 | Diploid |
•Means “one set” •Gametes or sex cells ◦Egg and sperm ◦Joined together during sexual reproduction to form a new organism. •Produced by the process of meiosis •Represented by the symbol N •For humans this is 23 | Haploid |
Name for body cells | Somatic |
Name for sex cells | Gamete |
1 cell becomes 2 Used by simple forms of life for reproduction. Ex: Bacteria and protists. Used by higher life forms to grow and repair damaged body cells. | asexual reproduction |
2 cells become 1 ◦Organisms create haploid cells that can join together during fertilization. ◦Cells are created through the process of meiosis. | sexual reproduction |
This is the division of the cytoplasm. •This starts to happen at the end of telophase. •This is when the organelles are divided between the two new cells as well. | cytokinesis |
The study of heredity. ◦Every living thing ‘inherits’ a set of characteristics from its parent | genetic |
Small changes in the genes of an organism create variation within populations. | variety of life |
A feature of an organism that varies from one individual to the next. The general groupings of traits. ◦Example: ◾Flower color ◾Skin tone, eye color, hair color | character |
A variant of a character ◾The specific colors or differences. ◾Blonde vs. brown hair ◾Pink vs. white flowers | trait |
The genetic make-up of an organism. •This cannot be seen by observing an organism. •They will be represented by capital and lower case letters. ◦TT, Tt, and tt | genotype |
The physical make-up of an organism (traits). •What can be seen by observing an individual. •This is what the genotype tells us. | phenotype |
The chemical factors located within the DNA that determines an organism’s traits. •The small changes in the larger shared genome are what make people unique. | genes |
The different forms of a gene. ◦Different combinations of alleles that you get from mom and dad will give you different expressions of the genes. | alleles |
Allele that will be expressed and determines an organism’s appearance. Denoted by a capital letter. | dominant allele |
An allele that when paired with a dominant allele has no effect on the organism. Denoted by a lower case letter. | recessive allele |
When an individual inherits two identical alleles for the same gene. Ex: BB, DD (dominant) or aa, tt (recessive) | homozygous |
When an individual inherits two different alleles for the same gene. Ex: Dd, Bb, or Aa -- these will express the dominant trait. | heterozygous |
The combination of male and female reproductive cells | fertilization |
occurs when an organism creates both the female and the male gametes and combines them. Plants are a good example of this. | Self-fertilization |
The two gametes combine which restores the diploid number The result of this combination is a ___________ | zygote |
Used to find the possible genotypes of a cross between two parents. | Punnet Squares |
A cross between two true breeding plants of different types. | hybrids |
Organisms differ in only one characteristic. | monohybrid cross |
If allowed to self-pollinate the organisms will produce offspring identical to themselves | true breeding |
When they are created the allele pairs separate or segregate from one another. You will only get one allele from each parent. | Gamete formation |
When the gametes are brought together the new organism will have two alleles, one from each parent. | Zygote formation |
Case in which one allele is not completely dominant over another. ◦Example: RR (red) and WW (white) create RW (pink) ◾Results in a blended phenotype. | Incomplete dominance |
A situation similar to incomplete dominance. In this situation both alleles contribute to the phenotype. ◦Example: Roan fur in cattle ◾Red and white spots of fur. | Codominance |
Gene has more than two alleles for a particular trait. •More than two possible alleles exist. ◦Example: coat color in rabbits | Multiple Alleles |
One gene determines the trait. •Individuals will either have the gene expressed (on) or not (off). ◦Examples: ◾Widow’s peak ◾Attached vs. unattached ear lobes ◾Digit hair | Single gene traits |
Traits that are created by the interaction of several genes. Literally means “many genes”. •These traits have a range in appearances. ◦Examples: ◾Human skin color ◾Human height | Polygenic |
Process in which one strain of bacteria is changed by a gene or genes from another strain of bacteria. | transformation |
He experimented with pneumonia causing bacteria. Discovered that when the two cultures were mixed, somehow the harmless bacteria had changed. | Frederick Griffith |
He started eliminating different parts of the bacteria to see what material actually held the instructions for the cell. He tested proteins, lipids, carbohydrates, and nucleic acids (DNA). | Oswald Avery |
When the DNA was destroyed transformation did not occur. •This lead to the understanding that the DNA of the cell help the genetic information | Oswald Avery |
Studied bacteriophages (virus that infects and kills bacteria). •Used radioactive markers to determine which part of the bacteriophage infects a cell. | Alfred Hershey and Martha Chase |
After cells were infected they looked to see if the marked proteins or the marked DNA were present. ◦The DNA was present. | Alfred Hershey and Martha Chase |
stores and transmits genetic information. | DNA |
_____________ are made from DNA. | Genes |
Discovered that DNA is a double-helix, in which two strands are wrapped around each other. (twisted ladder) --The twisted nature conserves space. | James Watson and Francis Crick |
__________________ bonds hold the two strands (sides) of the double helix (ladder) together. These bonds are sturdy enough to hold things together but breakable when needed. | Hydrogen |
DNA is ___________________. Nucleotides are the monomer. | polymer. |
DNA is polymer. Nucleotides are the ______________ | monomer. |
Nucleotide has three major components: | 5-carbon sugar deoxyribose (DNA) Phosphate group Nitrogenous bases |
These first two make up the sides of the ladder (the backbone of DNA) | Phosphate group |
The steps of the DNA ladder. | Nitrogenous bases |
2 types of nitrogenous bases | Purines and pyrimides |
Nucleotides with 2 rings | Purines |
The 2 purines | Adenine & Guanine “angels and gods are pure” |
Nucleotides with 1 ring | Pyrimides |
The two pyrimides | Cytosine and Thymine |
The 4 Nitrogenous Bases of DNA | Adenine, Guanine, Thymine, Cytosine |
One purine and one pyrimidine. ◦Bonds in DNA can only form between adenine and thymine (A-T) and between guanine and cytosine (G-C). | Base-Pairing |
Backbone of the DNA chain is formed by the ______ and ____________________ groups of each nucleotide. | sugar, phosphate |
DNA and proteins tightly packed together within the nucleus | chromatins |
Protein molecule around which the DNA is tightly coiled in chromatin. | histone |
prevents the chromatin from becoming tangled during mitosis. the individual bundles of DNA that is coiled about a histone. can then be super coiled into chromosomes for division. | nucleosomes |
Before a cell divides, it duplicates its DNA in a copying process called _______________________ | replication. |
the principal enzyme involved in DNA replication. Its job is to join individual nucleotides to produce the DNA molecule. It also proofreads each new DNA strand | DNA polymerase |
DNA molecule separates into two strands; forming _________________________ ____________ | replication forks. |
The synthesis of mRNA from a DNA template. Only one strand of DNA is copied. A single gene may be transcribed thousands of times. Afterward, the DNA strands rejoin. | transcription |
______________________ replaces thymine (T) in RNA | Uracil (U) |
a single strand of nucleotides. | RNA (ribonucleic acid) |
Type of RNA. Carries copies of instructions to make proteins from the DNA to the rest of the cell. This molecule is small enough to leave the nucleus unlike DNA. | Messenger RNA (mRNA) |
RNA that makes up a major part of the ribosome. Involved in protein synthesis | Ribosomal RNA (rRNA) |
RNA that transfers each amino acid (aa) to the ribosome during protein synthesis. Each molecule has an anticodon on it that codes for a specific amino acid. | Transfer RNA (tRNA) |
Proteins are made by joining _____________ _______(monomers) into long chains called polypeptides. | amino acids |
Proteins are made by joining amino acids (monomers) into long chains called _______________________ | polypeptides. |
_________________ are made by joining amino acids (monomers) into long chains called polypeptides. | Proteins |
Each amino acid is coded for with 3 bases which are part of a unit called a ____________ | codon |
The decoding of an mRNA message into a polypeptide chain. •Aka: Protein synthesis | Translation |
Where does protein synthesis/translation happen? | Takes place on the ribosomes ◦mRNA is transcribed in the nucleus, then enters the cytoplasm and attaches to a ribosome |
Group of three bases on a tRNA molecule that are complementary to an mRNA codon. ______________________ tells the tRNA molecule where to attach itself. | Anticodon |
Tells the tRNA molecule where to start and stop translating. | Start and Stop Codons AUG- start codon. UAA, UAG, UGA- stop codons |
Codons that release the finished chains into the cell to do its job. | stop codons |
The mRNA molecule moves through the ribosome and ___________molecule “translates” the codon and brings the proper amino acid. | tRNA |
___________ is transcribed in the nucleus, then enters the cytoplasm and attaches to a ribosome. | mRNA |
The part that reads the codons are called _____________. | anticodons |
Changes in the genetic material. Any change that occurs in DNA. Most are neutral. | Mutations |
Mutation that occurs at a single point in the DNA sequence. Involve changes in just one or a few nucleotides. | Point mutations |
When the reading frame is shifted one direction or the other due to an insertion or deletion, a ____________________ ______________ has taken place. This can disrupt the sequence of mutations. | frameshift mutation |
Mutations are also the source of genetic ________________ in a species. | variability |
Harmful mutations are the cause of many genetic _____________ | disorders |
change over time | evolution |
Went on a five year voyage around the world on the HMS Beagle. He collected plant and animal specimens at every stop. When he got back he then examined and categorized his specimens. | Charles Darwin |
Book published in 1859, nearly 25 years after his voyage. •Presented ideas that were met with strong feelings both in support of and against his findings. | On the Origin of Species |
Islands off of South America where Darwin studied tortoises and finches | Galapogos |
Organisms varied from one individual to another. Darwin noticed that plant and animal breeders used _______________ ______________ to improve crops and livestock. | inherited variations |
Selection by humans for breeding of useful traits from the natural variation among different organisms. Ex: domestic animals (dogs, cats) and crop plants | artificial selection |
individuals that are better suited to their environment survive and reproduce most successfully | natural selection (aka survival of the fittest) |
Ability of an individual to survive and reproduce in its specific environment. The result of adaptations. Low ____________results in death or fewer offspring. | Fitness |
Vestigial structures that have different mature forms but develop from the same embryonic tissue. | Homologous Structures Ex. forearm of reptiles, birds, and mammals These organisms are using similar body plans |
Organ or structure that serves no useful function in an organism Ex. pelvis and femur located in the tail of a whale. These animals have ancestors that lived on land and had four legs. | Vestigial Organs Ex. humans have appendix that use to help us process a rare meat diet. |
Consists of all genes, including all the different alleles, that are present in a population. | gene pool |
Two main sources of genetic variation | mutations and crossing over (Genetic shuffling that results from sexual reproduction.) |
the number of times that the alleles occurs in a gene pool, compared with the number of times other alleles for the same gene occur. Expressed in %. | Relative Frequency |
___________________ _____________ of traits can lead to changes in allele frequencies and thus to evolution. | Natural selection |
When individuals at the upper and lower ends of the curve have higher fitness than individuals near the middle. | disruptive selection |
When individuals near the center of a curve have higher fitness then individuals at either end. | Stabilizing selection |
Individuals at one end of the curve have higher fitness than individuals in the middle or at the other end. | Directional selection |