Biology Flashcards
Dependent Variable
Observed variable that may or may not change in response to the independent variable.
Independent Variable
Factor in a controlled experiment that is intentionally or deliberately changed.
Control Group
Exposed to the identical conditions of the experimental group with the exception of the independent variable.
Hypothesis
Scientific explanation for set of observations that can be tested in a way that support or reject it.
Controlled Experiment
Testing a hypothesis by tracking various factors that can change (variables). Only one variable should be intentionally changed while others remain constant.
Asexual Reproduction
A single organism produces offsprings that are genetically similar to itself.
Sexual Reproduction
Cells from two parents unite to form the first cell of a new organism.
Metabolism
Combination of chemical reactions through which an organism builds up or breaks down materials.
Homeostasis
A relatively stable internal environment.
Ionic Bond
Formed when two or more electrons are transferred from one atom to another.
Covalent Bond
The bond formed when atoms share electrons.
Ions
Atoms with a positive or negative charge.
Isotope
Atoms of the same element that differ in the number of neutrons.
Element
A chemically pure substance with only one type of atom.
Electron
Negatively charged atomic particles; are in constant motion around the nucleus.
Neutron
Atomic particles with no charge.
Proton
Positively charged atomic particles.
Molecule
Smallest unit of most compounds.
Monomer
Small chemical unit that makes up a polymer.
Polymer
Molecules composed of many monomers; makes up macromolecules.
Carbohydrate
Compounds made of carbon, hydrogen, and oxygen atoms- usually in a ratio of 1:2:1.
What is the main source of energy for living things?
Carbohydrates
Monosaccharide
Single sugar molecules.
Lipid
Mostly made of carbon and hydrogen atoms. (Fats, oils, waxes)
Nucleic Acid
Macromolecules containing hydrogen, carbon, oxygen, phosphorus.
Nucleotide
Consists of a 5-carbon sugar, phosphate group, and a nitrogen base.
Protein
Macromolecules that contain nitrogen as well as carbon, hydrogen, and oxygen.
Amino Acid
Compounds with an amino group on one end and a carboxyl group on the other end.
Reactant
Elements or compounds that enter into a chemical reaction; input.
Products
Elements or compounds produced Ina chemical reaction; outcome.
Catalyst
Substance that speeds the reaction process.
Enzyme
Biological catalyst
Activation Energy
The energy that is needed to get a reaction started.
Hydrogen Bond
The attraction between a hydrogen atom with a partial positive charge and an atom with a partial negative charge.
Adhesion
An attraction between molecules of different substances.
Cohesion
Attraction between molecules of the same substance.
Solute
Substance that is dissolved in a solution.
Solvent
Substance in which another substance is dissolved in a solution.
Solution
A type of mixture where all components are evenly distributed.
Suspension
Mixtures of water and non-dissolved materials.
Buffer
Weak acids or bases that can react with strong acids or bases to prevent sudden, sharp changes in pH.
Acid
PH of less than seven; contains higher concentration of hydrogen atom than water.
Base
PH greater than seven; contains higher concentration of hydroxide ions.
pH Scale
Measurement system developed to indicate the concentration of hydrogen ions in a solution.
Why do cells divide?
Cell division reduces information overload and material exchange issues.
What does the rate at which materials are exchanged through the cell membrane depend on?
The surface area.
What does the rate at which food and oxygen are used and waste is produced depend on?
The volume.
True or False: Larger cells have a smaller surface area to volume ratio compared to smaller cells.
True
What happens to the surface area to volume ratio as the cell grows larger?
The surface area to volume ratio gets smaller.
When do spindle fibers attach to centromeres?
Metaphase
When does the nuclear membrane dissolve?
Prophase
When are centrioles at opposite ends of the cells?
Metaphase
When do spindle fibers begin to form?
Prophase
When do centrioles begin to separate?
Prophase
When are sister chromatids pulled apart and separate?
Anaphase
When do chromosome line up in the center of the cell?
Metaphase
When do spindle fibers disappear?
Telophase
When do spindle fibers shorten bringing chromatids to opposite ends of a cell?
Anaphase
When do chromatids condense forming chromosomes and become visible?
Prophase
When does the nuclear membrane form around the sister chromatids?
Telophase
This is when the cell takes is nutrients and eliminates wastes through the cell membrane.
Exchange of materials.
This solves the information overload and material exchange problems.
Cell division.
This type of reproduction…
- Produces genetically identical offspring
- Occurs in many single-celled organisms
Asexual Reproduction
This type of reproduction…
- Produces organisms with genetic information from both parents.
- Occurs in most animals and plants
Sexual Reproduction
True or False: As a cell’s size increases, its amount of DNA also increases.
True
True or False: The amount of activity in a cell is related to its volume.
True
True or False: The smaller the cell, the smaller its ratio of surface area to volume.
False
Packages of DNA are called ____.
Chromosomes
This is the series of events in the growth and division of a cell.
The cell cycle
The first three stages of mitosis (the G1 phase, S phase, and G2 phase) are referred to as____.
Interphase
What happens in the G1 phase of mitosis?
The cell grows
What happens in the S phase of mitosis?
DNA is replicated
What happens in the G2 phase of mitosis?
The cell produces organelles and materials for for division.
In which phase does the cell divide into two stages-mitosis and cytokinesis?
In the M-phase
In this phase of M-stage, the nucleus divides.
Mitosis
In this stage of mitosis, the cytoplasm divides.
Cytokinesis
Name the stage of mitosis:
A cell’s genetic material condenses, a spindle starts to form, and the nuclear envelope breaks down.
Prophase
Name the stage of mitosis:
The duplicated chromosomes line up in the middle of the cell and spindle fibers connect to the centromeres.
Metaphase
Name the stage of mitosis:
Sister chromatids separate and move towards the centrioles.
Anaphase
Name the stage of mitosis:
The chromosomes begin to unwind and a nuclear envelope reforms.
Telophase
Explain cytokinesis in animal cells.
The cell membrane draws in and pinches off.
Explain cytokinesis in plant cells.
A cell plate forms, followed by a new membrane, and finally a new cell wall forms.
These are proteins that regulate the timing of the cell cycle in eukaryotic cells.
Cyclins
(Internal/External) regulators allow the cell cycle to proceed when certain events have occurred within a cell.
Internal
(Internal/External) regulators called growth factors stimulate the cell cycle. Other regulators of this type cause the cell cycle to slow down or stop.
External
This is a programmed cell death that plays a key role in the development of tissues and organs.
Apoptosis
This is disorder in which cells divid uncontrollably, forming a mass of cells called a tumor.
Cancer
Give at least one treatment for cancer.
One of these choices:
- Removal of cancerous tumors
- Radiation
- Chemotherapy
True or False: Cells tend to continue dividing when they come in contact with other cells.
False
In what type of cell does the cell cycle occur?
a. ) Prokaryotes
b. ) Eukaryotes
b.) Eukaryotes
The is scientific study of heredity.
Genetics
Why did Gregor Mendel choose peas to work with?
At least one of these choices:
- Easy to work with
- There was a wide variety of traits
- Common and easily accessible
Gregor Mendel took the pollen off of one flower and transferred it to the female stigma of another flower.
What is it called?
Cross-pollination
This is a specific characteristic that varies from one individual to another.
Trait
What is does the P generation stand for? What is it?
Parental; the first generation studied.
What does the F1 generation mean?
First Filial Generation
What does the F2 generation mean?
Second Filial Generation
This is the offspring of crosses between parents with different traits.
Hybrid
Give at least one reason why Gregor Mendel was unique.
At least one of these choices:
- he did thousands of trials
- he studied more than one trait
- explained results using probability
The type of trait that appeared in the F1 generation every time.
Dominant Trait
The hidden trait, seemed to disappear in the F1 generation.
Recessive
These are factors that determine traits.
Genes
Which principle or law of Mendel’s said this?
Some alleles are dominant and others are recessive?
Principle of Dominance
What is Mendel’s Law of Segregation?
When a gamete forms, two alleles must separate.
What is the mathematical chance that something will occur called (also: the likely hood that an event will occur)?
Probability
Which principle is used to predict the outcome of genetic crosses?
Principles of Probability
What is used to predict outcomes of crosses?
A punnett square
What are organisms that have the same alleles for a trait called (e.g. AA or aa)
Homozygous
What are organisms that have different alleles for a trait called (e.g. Aa)
Heterozygous
What does phenotype mean?
Physical appearance of a trait
What does genotype mean?
The genetic make-up
What kind of cross looks at one particular trait?
Monohybrid
Which of these says that alleles assort independently during fertilization?
a. ) Monohybrid Cross
b. ) Independent Assortment
c. ) Dominance
b.) Independent Assortment
What is it called when neither allele is completely dominant of another?
Incomplete dominance
What is it called when there are more than 2 alleles for a specific gene?
Multiple Alleles
What is it called when traits are controlled by many different genes?
Polygenic traits
_____ is when both alleles in the heterozygous genotype are expressed (not a blending).
Codominance
True or False: Genes can be influenced by environmental factors.
True
Temperature, availability of food/nutrients, disease, and chemicals are all examples of _____.
Environmental factors
____chromosomes are chromosomes that contain the same same genes
Homologous
What is the symbol for diploid cells?
2n
What is the symbol for haploid cells?
n
Body cells are (diploid or haploid) cells.
Diploid
Gametes are (diploid or haploid) cells.
Haploid
If an organism’s diploid cells contain 46 chromosomes, how many chromosomes are in the haploid cells?
23
What are made in meiosis?
Haploid gametes
In what phase of meiosis do tetrads form?
Prophase 1
In what phase of meiosis does crossing over occur?
Prophase 1
True or False: After meiosis, there are 4 daughter cell, and they are genetically identical.
False
In this stage of meiosis, chromosomes are pulled away and they are NOT separated into two parts.
Anaphase 1
After meiosis I, _____ is skipped and the cells go directly into prophase II.
Interphase
Which scientist found that Gregor Mendel’s experiment and conclusions apply to all organisms, both plant and animal?
Thomas Hunt Morgan
____ are constructed by looking at frequencies of crossing over.
Gene Maps
Which scientist worked with mice and different strains of bacteria to discover transformation?
Frederick Griffith
____ is the process in which one strain of bacteria by a gene or genes from another strain of bacteria.
Transformation
This scientist used extracts, each treated with enzymes that destroyed a certain substance that could cause Griffith’s transformation.
Oswald Avery
Which scientist first discovered what was causing Griffith’s transformation?
Oswald Avery
Oswald Avery’s conclusion was that _____ was not protein, passed the disease from the bacteria to the mice.
DNA
The smooth strain of bacteria that Frederick Griffith use was (good or bad).
Bad
The rough strain of bacteria that Frederick Griffith used was (good or bad).
Good
Alfred Hershey and Martha Chase used ____ to label proteins and DNA in bacteriophages.
Radioactive materials
What happened when Frederick Griffith injected the mice with the bad, smooth, strain of bacteria?
They died.
What are the four nitrogenous bases that DNA has?
Adenine (A), Thymine (T), Guanine (G), Cytosine (C)
Which of the five bases does DNA NOT have?
Uracil (U)
_____ showed that the percentages of adenine and thymine are almost always equal in DNA Mendel’s conclusions.
Chargaff’s Rule
Which scientist looked at DNA with an x-ray and saw that it was double stranded?
Rosalind Franklin
What kind of bonds holds the two DNA strands together?
Hydrogen or covalent
Adenine only pairs with _______ in DNA.
Thymine (T)
Cytosine only pairs with _______ in DNA.
Guanine (G)
If DNA contains 36% of guanine, how much cytosine is in the DNA?
36%
DNA copies itself through the process of ______.
Replication
What does DNA form when the two strands of the double helix unzips?
A replication fork
DNA _____ is an enzyme that joins individual nucleotides to produce a new strand of DNA.
Polymerase
What are the tips of chromosomes called?
Telomeres
True or False: Prokaryotic cells have much more DNA than eukaryotic cells.
False
How many points does replication start in most prokaryotic cells?
One
Which way(s) (e.g. up, down) does replication occur in eukaryotic cells?
Up and down
What is the start amino acid?
Methionine
What does the “t” in tRNA stand for?
Transfer
What does the “m” in mRNA stand for?
Messenger
Where does transcription take place?
In the nucleus of the cell
What does “r” in rRNA stand for?
Ribosomal
Who was the first person to see and identify cells?
Robert Hooke
What are the 3 components to the cell theory?
- ) cells are the basic unit of life
- ) all living things are composed of cells
- ) new cells are produced from existing cells
What does a confocal light microscope do?
Builds 3-D image.
What does a transmission electron microscope do?
It uses electrons to pass through thin samples.
What does a scanning electron microscope do?
It operates in air and in a solution to produce 3-D images.
Why are fluorescent labels used?
To study molecules in a cells. (Such as organelles)
What 2 characteristics must a cell have?
1.) it must be surrounded by a cell membrane2.) it must contains DNA (genetic info)
What is the difference between eukaryotes and prokaryotes? Example of each?
Eukaryotes contain a nucleus and prokaryotes do not. Eukaryotes- animal and plant cellsProkaryotes- bacteria
True of False: Eukaryotes are more complex than prokaryotes.
True
True of false: Prokaryotes are much larger than eukaryotes.
False
What is a small molecule that functions within a cell?
An organelle
What is the portion of the cell outside the nucleus?
Cytoplasm
Which 2 microscopes build a 3D image?
Confocal light microscope and the scanning electron microscope
Which microscopes use electrons?
Scanning ELECTRON microscope and transmission ELECTRON microscope.
Where is DNA found in the cell?
Nucleus
What is chromatin and where is it found in the cell?
DNA bound to protein; the nucleus.
What is the function of a nucleolus?
It is where ribosome assembly begins.
What contains pores allowing protein, RNA, etc. into and out of the cell?
Nuclear envelope.
What are ribosomes composed of?
RNA and protein.
What do ribosomes do?
They assemble proteins based on instructions from the nucleus.
What is the function of the Rough ER?
Synthesized proteins that are being exported out of the cell.
What is the function of the Smooth ER?
It synthesizes membrane lipids detoxifies drugs. (Commonly found in the liver)
What is the difference between the smooth ER and rough ER?
The rough ER is covered in ribosomes giving it a rough appearance and the smooth ER is not.
What is the function of the Golgi apparatus?
It modifies, sorts, and packages proteins for storage or secretion and receives proteins for the Rough ER.
What are the functions of lysosomes?
Filled with digestive enzymes in order to digest lipids, carbs, and proteins while breaking down old organelles.
What is the function of a vacuole?
Stores water, salt, proteins, and carbohydrates while maintains the cells homeostasis. Serve as structural support in plants.
What makes the chloroplasts and mitochondria different from the rest of the organelles?
They have a double membrane and both contain their own DNA
What is the function of the mitochondria?
Converts chemical energy stored in food into compounds more useful to the cell.
What is the function of a chloroplast?
It is found is plants and captures energy from the sun and converts it into a chemical energy.
What organelle(s) are found in plant cells but not animal?
Chloroplasts and cell wall
What is the cytoskeleton?
A network of protein filaments that are mostly used for movement and structure.
What do the centrioles do?
They organize cell division.
What does the cell membrane have the helps move materials from in and out of the cell? What are they made out of?
Protein channels made out of protein.
Define diffusion.
The movement of particles from a higher concentration tons lower.
Define osmosis.
The movement of water molecules from a higher concentration to a lower.
Define facilitated diffusion.
Transporting molecules that are too big for diffusion into the membrane using protein channels.
What is active transport?
The movement AGAINST the concentration gradient and requires energy.
What is the function of a cell membrane?
1.) regulation2.) protection3.) support
What are the two parts of a membrane
Head: phosphate Tail: fatty acid
What is the function of a cell wall?
To provide support and protection.
What is the cell membrane composed of?
Carbohydrate fibers and proteins.
What are the levels of organization of cells?
Cells TissueOrganOrgan system
What are two examples of endocytosis?
Pinocytosis and phagocytosis
Define pinocytosis.
Taking in fluid. (To drink)
Define phagocytosis.
Taking in chunks. (To eat)
Define endocytosis.
To take in by engulfing. (Amoeba do this)
How to find concentration?
Mass of solutes per volume of solution.
Define equilibrium.
When the system has same concentration throughout; no net movement.
Isotonic
When concentration is equal
Hypotonic
More diluted side.
Hypertonic
More concentrated side
Define osmotic pressure.
Pressure on the hypertonic side of selectively permeable membrane.
Why aren’t animal cells harmed by osmotic pressure?
Blood is isotonic.
Why aren’t plant cells harmed by osmotic pressure?
Plants have a rigid cell wall.
Define exocytosis.
Releasing large amounts of material from the cell by having a vacuole surround the material and fuse with the cell membrane.
What is the most abundant life form?
Unicellular organisms (single-celled organism)
Cell specialization
Cells developing in different ways to preform different tasks.
Who was the first person to see and identify cells?
Robert Hooke
What are the 4 components to the cell theory?
1.) cells are the basic unit of life2.) all living things are composed of cells3.) cells are the basic units of structure and function in living things4.) new cells are produced from existing cells
What are the similarities between a transmission electron microscope, scanning electron microscope, and confocal light microscope?
All are used to be able to see cells on a molecular level.
What does a confocal light microscope do?
Builds 3-D image.
What does a transmission electron microscope do?
It uses electrons to pass through thin samples.
What does a scanning electron microscope do?
It operates in air and in a solution to produce 3-D images.
Why are fluorescent labels used?
To study molecules in a cells. (Such as organelles)
What 2 characteristics must a cell have?
1.) it must be surrounded by a cell membrane2.) it must contains DNA (genetic info)
What is the difference between eukaryotes and prokaryotes? Example of each?
Eukaryotes contain a nucleus and prokaryotes do not. Eukaryotes- animal and plant cellsProkaryotes- bacteria
True of False: Eukaryotes are more complex than prokaryotes.
TRUE
True of false: Prokaryotes are much larger than eukaryotes.
FALSE
What is a small molecule that functions within a cell?
An organelle
What is the portion of the cell outside the nucleus?
Cytoplasm
What is the center of cell? (Control center)
Nucleus
Which 2 microscopes build a 3D image?
Confocal light microscope and the scanning electron microscope
Which microscopes use electrons?
Scanning ELECTRON microscope and transmission ELECTRON microscope.
Where is DNA found in the cell?
Nucleus
What is chromatin and where is it found in the cell?
DNA bound to protein; the nucleus.
What is the function of a nucleolus?
It is where ribosome assembly begins.
What contains pores allowing protein, RNA, etc. into and out of the cell?
Nuclear envelope.
What are ribosomes composed of?
RNA and protein.
What do ribosomes do?
They assemble proteins based on instructions from the nucleus.
What is the function of the Rough ER?
Synthesized proteins that are being exported out of the cell.
What is the function of the Smooth ER?
It synthesizes membrane lipids detoxifies drugs. (Commonly found in the liver)
What is the difference between the smooth ER and rough ER?
The rough ER is covered in ribosomes giving it a rough appearance and the smooth ER is not.
What is the function of the Golgi apparatus?
It modifies, sorts, and packages proteins for storage or secretion and receives proteins for the Rough ER.
What are the functions of lysosomes?
Filled with digestive enzymes in order to digest lipids, carbs, and proteins while breaking down old organelles.
What is the function of a vacuole?
Stores water, salt, proteins, and carbohydrates while maintains the cells homeostasis. Serve as structural support in plants.
What makes the chloroplasts and mitochondria different from the rest of the organelles?
They have a double membrane and both contain their own DNA
What is the function of the mitochondria?
Converts chemical energy stored in food into compounds more useful to the cell.
What is the function of a chloroplast?
It is found is plants and captures energy from the sun and converts it into a chemical energy.
What organelle(s) are found in plant cells but not animal?
Chloroplasts and cell wall
What is the cytoskeleton?
A network of protein filaments that are mostly used for movement and structure.
What do the centrioles do?
They organize cell division.
What does the cell membrane have the helps move materials from in and out of the cell? What are they made out of?
Protein channels made out of protein.
Define diffusion.
The movement of particles from a higher concentration tons lower.
Define osmosis.
The movement of water molecules from a higher concentration to a lower.
Define facilitated diffusion.
Transporting molecules that are too big for diffusion into the membrane using protein channels.
What is active transport?
The movement AGAINST the concentration gradient and requires energy.
What is the function of a cell membrane?
1.) regulation2.) protection3.) support
What are the two parts of a membrane
Head: phosphate Tail: fatty acid
What is the function of a cell wall?
To provide support and protection.
What is the cell membrane composed of?
Carbohydrate fibers and proteins.
What are the levels of organization of cells?
Cells TissueOrganOrgan system
What are two examples of endocytosis?
Pinocytosis and phagocytosis
Define pinocytosis.
Taking in fluid. (To drink)
Define phagocytosis.
Taking in chunks. (To eat)
Define endocytosis.
To take in by engulfing. (Amoeba do this)
How to find concentration?
Mass of solutes per volume of solution.
Define equilibrium.
When the system has same concentration throughout; no net movement.
Isotonic
When concentration is equal
Hypotonic
More diluted side.
Hypertonic
More concentrated side
Define osmotic pressure.
Pressure on the hypertonic side of selectively permeable membrane.
Why aren’t animal cells harmed by osmotic pressure?
Blood is isotonic.
Why aren’t plant cells harmed by osmotic pressure?
Plants have a rigid cell wall.
Define exocytosis.
Releasing large amounts of material from the cell by having a vacuole surround the material and fuse with the cell membrane.
What is the most abundant life form?
Unicellular organisms (single-celled organism)
Cell specialization
Cells developing in different ways to preform different tasks.
What is the ratio of matter’s mass to its volume?
Density
The overall charge of an atom is _______.
Neutral
What are the four major elements for biological importance?
Carbon, hydrogen, oxygen, nitrogen.
What is the small dense region within most nuclei in which the assembly of proteins begin?
nucleolus
What is a Scanning Electron Microscope?
It forms a 3-D image by using electrons to scan surfaces.
What is a Transmission Electron Microscope?
It shines beams of electrons to form a 2-D image?
What is a tetrad?
A homologous chromosome pair.
What is a Compound Light Microscope?
It is used to see living things (microscopes in class).
What is the control?
A variable that does not change.
The experimental group is the group that contains the _________ variable.
Independent
The larger knob on a microscope used to move the stage up or down.
Course Adjustment
What provides the light source that will shine through a specimen in a microscope?
Lamp
The ______ lens provides magnification.
objective
This is the lens you look through.
ocular lens
The part of the microscope you grab to carry.
the arm
What are the 8 characteristics of a living thing?
- ) Made up of one or more cells.
- ) Has DNA
- ) Able to maintain Homeostasis
- ) Capable of reproduction
- ) Grows and develop
- ) Obtain and use materials for energy (metabolism)
- ) Able to respond to their environment.
- ) Able to evolve as a species.
What are the steps to the scientific method in order?
- ) State the problem
- ) Gather information
- ) Form a hypothesis
- ) Test the hypothesis.
- ) Analyze data
- ) Make a conclusion
- ) Repeat
What is the difference between atomic and mass number?
Atomic- # of protons
Mass- # of protons and neutrons
What are chemical properties?
Quality that can be established only by changing a substance’s chemical identity.
What are physical properties?
Quality you can observe or quality in a certain state of matter.
How can be enzyme activity can be regulated?
pH, temperature, other enzymes
What are 4 major organic compounds for biological importance?
Carbohydrates, lipids, nucleic acids, proteins.
What does Biuret test for?
Protein
What does Benedict’s solution test for?
Monosaccharides
What does brown paper test for?
Lipids
What does iodine test for?
polysaccharides
The removal of water when a compound is formed is called __________.
dehydration synthesis
The internal membrane system in cells in which lipid components of the cell membrane are assembled and one proteins are modified.
Endoplasmic Reticulum
Cell organelle filled with enzymes needed to break down certain materials in the cell.
Lysosome
Cell organelle that converts the chemical energy stored in food into compounds that are more convenient for the cell to use.
Mitochondria
Found in chloroplasts and mitochondria
Organelle DNA
Network of protein filaments within some cells that helps the cell maintain its shape.
Cytoskeleton
Structure that contains the cell’s genetic material and controls the cell’s activities.
Nucleus
Granular material visible within the nucleus; consists of DNA tightly coiled around proteins.
Chromatin
Threadlike structure within the nucleus containing the genetic information that is passed from one generation of cells to the next. (condensed chromatin)
Chromosomes
