Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > Biology Vocabulary > Flashcards

Biology Vocabulary Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Evolution

A

Is change in the heritable characteristics of biological populations over successive generations/long period of time. These characteristics are the expressions of genes that are passed on from parent to offspring during reproduction. Different characteristics tend to exist within any given population as a result of mutation, genetic recombination and other sources of genetic variation. Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain characteristics becoming more common or rare within a population. It is this process of evolution that has given rise to biodiversity at every level of biological organisation, including the levels of species, individual organisms and molecules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The scientific theory of evolution by natural selection was conceived by?

A

Charles Darwin and Alfred Russel Wallace in the mid-19th century in Darwin’s book: On the Origin of Species.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Gene

A

A heritable unit for transmission of biological traits.

A sequence of nucleotides in DNA or RNA that encodes the synthesis of a gene product, either RNA or protein.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Phenotype

A

pheno- ‘showing’, and ‘type’) the term used in genetics for the composite observable characteristics or traits of an organism.
The term covers the organism’s morphology or physical form & structure, its developmental processes, its biochemical and physiological properties, its behavior, and the products of behavior. An organism’s phenotype results from two basic factors: the expression of an organism’s genetic code (genotype) & the influence of environmental factors. Both factors may interact, further affecting phenotype.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Genotype

A

is an organism’s set of heritable genes that can be passed down from parents to offspring.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Polymorphism

A

is when there are two or more possibilities of a trait (phenotypes) on a gene in a population.
ie. more than 1 possible trait of jaguar’s skin coloring (dark morph or light morph).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Punnett square

A

is a square diagram used to predict the genotypes of a particular cross or breeding experiment. The diagram is a tabular summary of possible combinations of maternal alleles with paternal alleles. These tables can be used to examine the genotypical outcome probabilities of the offspring of a single trait (allele), or when crossing multiple traits from the parents. The Punnett square is a visual representation of Mendelian inheritance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Allele

A

is a variant form of a gene. Some genes have a variety of different forms, which are located at the same position, or genetic locus, on a chromosome.
Humans are called diploid organisms because they have two alleles at each genetic locus, with one allele inherited from each parent. Each pair of alleles represents the genotype of a specific gene. Genotypes are described as homozygous if there are two identical alleles at a particular locus and as heterozygous if the two alleles differ. Alleles contribute to the organism’s phenotype, which is the outward appearance of the organism.

Some alleles are dominant or recessive. When an organism is heterozygous at a specific locus and carries one dominant and one recessive allele, the organism will express the dominant phenotype. Alleles can also refer to minor DNA sequence variations between alleles that do not necessarily influence the gene’s phenotype.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Evolution = Natural Selection

A

Genetic Variation over long periods of time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Chromosome

A 
“Chromo” = “Colored” 
“Some” = “Body”

is a long DNA molecule with part or all of the genetic material of an organism. Most eukaryotic chromosomes include packaging proteins called histones which, aided by chaperone proteins, bind to and condense the DNA molecule to maintain its integrity. These chromosomes display a complex three-dimensional structure, which plays a significant role in transcriptional regulation.

Chromosomes are normally visible under a light microscope only during the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, each chromosome is duplicated (S phase), and both copies are joined by a centromere, resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. The joined copies are now called sister chromatids. During metaphase the X-shaped structure is called a metaphase chromosome, which is highly condensed and thus easiest to distinguish and study. In animal cells, chromosomes reach their highest compaction level in anaphase during chromosome segregation.

Chromosomal recombination during meiosis and subsequent sexual reproduction play a significant role in genetic diversity. If these structures are manipulated incorrectly, through processes known as chromosomal instability and translocation, the cell may undergo mitotic catastrophe. Usually, this will make the cell initiate apoptosis leading to its own death, but sometimes mutations in the cell hamper this process and thus cause progression of cancer.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Eukaryote

A 
“Eu” = “well”/“good”
“Karyon” = “nut”/“kernel”

is an organism with complex cells, or a single cell with a complex structures. In these cells the genetic material is organized into chromosomes in the cell nucleus.

Eukaryotes Examples are:
Animals, plants, algae, fungi (mushrooms), single-celled protists (ie. amoeba & paramecium), Insects, & Humans are composed entirely of eukaryotic cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Prokaryote

A 
“Pro” = “before”
“Karyon” = “nut”/“kernel”

a microscopic single-celled organism that has neither a distinct nucleus with a membrane nor other specialized organelles. Prokaryotes include the bacteria and cyanobacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Centromere

A

is a structure in a chromosome that holds together the two chromatids (the daughter strands of a replicated chromosome). The centromere is the point of attachment of the kinetochore, a structure to which the microtubules of the mitotic spindle become anchored.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Chromatin

A

is the material that makes up a chromosome that consists of DNA & protein. The major proteins in chromatin are proteins called histones. They act as packaging elements for the DNA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Chromatid

A

is one of two identical halves of a replicated chromosome. During cell division, the chromosomes first replicate so that each daughter cell receives a complete set of chromosomes.

is one half of a duplicated chromosome. Before replication, one chromosome is composed of one DNA molecule. Following replication, each chromosome is composed of two DNA molecules; in other words, DNA replication itself increases the amount of DNA but does not increase the number of chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

(Genotype) Fitness

A

is a measure of survival, mate-find, & reproductive success (how many offspring an organism leaves in the next generation, relative to others in the group). Natural selection can act on traits determined by alternative alleles of a single gene, or on polygenic traits (traits determined by many genes).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

DNA

A

Deoxyribonucleic acid is a self-replicating molecule composed of two polynucleotide chains that coil around each other to form a double helix carrying genetic instructions for the development, functioning, growth and reproduction of all known organisms and many viruses. DNA and ribonucleic acid are nucleic acids.

DNA examples include: animals, plants, protists, archaea and bacteria. DNA is in each cell in the organism and tells cells what proteins to make.

DNA has a phosphate deoxyribose backbone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Genome

A

is an organism’s complete set of genetic instructions. Each genome contains all of the information needed to build that organism and allow it to grow and develop.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Nucleobase

A

There are a total of 5 nucleobases in DNA and RNA. These are cytosine, guanine, adenine (found in both DNA and RNA), thymine (found only in DNA), and uracil (found only in RNA). In DNA, adenine pairs with thymine, while cytosine pairs with guanine.

Nucleobases, also known as nitrogenous bases containing biological compounds that form nucleosides, which, in turn, are components of nucleotides, with all of these monomers constituting the basic building blocks of nucleic acids. The ability of nucleobases to form base pairs and to stack one upon another leads directly to long-chain helical structures such as ribonucleic acid (RNA) and deoxyribonucleic acid (DNA).

Five nucleobases—adenine (A), cytosine (C), guanine (G), thymine (T), and uracil (U)—are called primary or canonical. They function as the fundamental units of the genetic code, with the bases A, G, C, and T being found in DNA while A, G, C, and U are found in RNA.

Thymine and uracil are distinguished by merely the presence or absence of a methyl group on the fifth carbon (C5) of these heterocyclic six-membered rings.

Adenine and guanine have a fused-ring skeletal structure derived of purine, hence they are called purine bases. The purine nitrogenous bases are characterized by their single amino group (NH2), at the C6 carbon in adenine and C2 in guanine.

Similarly, the simple-ring structure of cytosine, uracil, and thymine is derived of pyrimidine, so those three bases are called the pyrimidine bases.

Each of the base pairs in a typical double-helix DNA comprises a purine and a pyrimidine: either an A paired with T (or) C paired with a G. These purine-pyrimidine pairs, which are called base complements, connect the two strands of the helix and are often compared to the rungs of a ladder. The pairing of purines and pyrimidines may result, in part, from dimensional constraints, as this combination enables a geometry of constant width for the DNA spiral helix. The A-T and C-G pairings function to form double or triple hydrogen bonds between the amine and carbonyl groups on the complementary bases.

Nucleobases such as adenine, guanine, xanthine, hypoxanthine, purine, 2,6-diaminopurine, and 6,8-diaminopurine may have formed in outer space as well as on earth.The origin of the term base reflects these compounds’ chemical properties in acid-base reactions, but those properties are not especially important for understanding most of the biological functions of nucleobases.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

RNA

A

ribonucleic acid is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and DNA are nucleic acids which are present in all living cells.
RNA is single-stranded. An RNA strand has a backbone made of alternating sugar (ribose) and phosphate groups.

There are 4 types of RNA, each encoded by its own type of gene:

mRNA - Messenger RNA: Encodes amino acid sequence of a polypeptide.

tRNA - Transfer RNA: Brings amino acids to ribosomes during translation.

rRNA - Ribosomal RNA: With ribosomal proteins, makes up the ribosomes, the organelles that translate the mRNA.

snRNA - Small nuclear RNA: With proteins, forms complexes that are used in RNA processing in eukaryotes. (Not found in prokaryotes.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

mRNA

A

mRNA - Messenger RNA: Encodes amino acid sequence of a polypeptide.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

tRNA

A

tRNA - Transfer RNA: Brings amino acids to ribosomes during translation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

rRNA

A

rRNA - Ribosomal RNA: With ribosomal proteins, makes up the ribosomes, the organelles that translate the mRNA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

snRNA

A

snRNA - Small nuclear RNA: With proteins, forms complexes that are used in RNA processing in eukaryotes. (Not found in prokaryotes.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Amino Acids (AA)

A

are the building blocks of proteins.

In eukaryotes, there are 20 standard amino acids out of which almost all proteins are made.

In biochemistry, an amino acid is any molecule that has both amine (NH2+R) and carboxyl (C=O) functional groups.

amino group (—NH2)
carboxyl group (—COOH)
26
Q

Codon

A

a sequence of 3 nucleotides which together form a unit of genetic code in a DNA or RNA molecule that specifies a particular amino acid in a protein or starts or stops protein synthesis. — called also triplet.

27
Q

Essential Amino Acids

A

cannot be made by the body & must come from food.

(9) essential amino acids:
L-histidine
L-isoleucine
L-leucine
L-lysine, 
L-methionine
L-phenylalanine
L-threonine
L-tryptophan
L-valine
28
Q

Non-Essential Amino Acids

A

support tissue growth and repair, immune function, red blood cell formation, and hormone synthesis

(11) non-essential amino acids:
alanine
arginine
asparagine
aspartic acid
cysteine
glutamic acid
glutamine
glycine
proline
serine
tyrosine
29
Q

Cell

A

the basic membrane-bound unit that contains the fundamental molecules of life and of which all living things are composed. A single cell is often a complete organism in itself (ie. a bacterium or yeast).

30
Q

Nucleus

A

contains the cell’s genes and controls the cell’s growth and reproduction. … The nucleus is usually the most prominent organelle in a cell. The nucleus is small and round, and works as the cell’s control center. It contains chromosomes which house the DNA.

31
Q

Ribosome

A

a minute particle consisting of RNA and associated proteins found in large numbers in the cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize polypeptides and proteins.

32
Q

Mitochondria

A

an organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur. It has a double membrane, the inner layer being folded inward to form layers (cristae).

33
Q

Golgi Apparatus

A

a complex of vesicles and folded membranes within the cytoplasm of most eukaryotic cells, involved in secretion and intracellular transport.

34
Q

Cytoplasm

A

is a thick solution that fills each cell and is enclosed by the cell membrane. It is mainly composed of water, salts, and proteins. In eukaryotic cells, the cytoplasm includes all of the material inside the cell and outside of the nucleus.

35
Q

Nucleolus

A

a small dense spherical structure in the nucleus of a cell during interphase.

36
Q

Endoplasmic Reticulum

A

a network of membranous tubules within the cytoplasm of a eukaryotic cell, continuous with the nuclear membrane. It usually has ribosomes attached and is involved in protein and lipid synthesis.

37
Q

Rough Endoplasmic Reticulum (RER)

A

series of connected flattened sacs, part of a continuous membrane organelle within the cytoplasm of eukaryotic cells, that plays a central role in the synthesis of proteins.

38
Q

Smooth Endoplasmic Reticulum (SER)

A

is a membranous organelle found in most eukaryotic cells. Its main functions are the synthesis of lipids, steroid hormones, the detoxification of harmful metabolic byproducts and the storage and metabolism of calcium ions within the cell.

39
Q

Chloroplast

A

(in green plant cells) a plastid that contains chlorophyll and in which photosynthesis takes place.

40
Q

Chlorophyll

A

a green pigment, present in all green plants and in cyanobacteria, responsible for the absorption of light to provide energy for photosynthesis. Its molecule contains a magnesium atom held in a porphyrin ring.

41
Q

Photosynthesis

A

the process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water. Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a byproduct.

42
Q

Lysosome

A

is a membrane-bound cell organelle that contains digestive enzymes. Lysosomes are involved with various cell processes. They break down excess or worn-out cell parts. They may be used to destroy invading viruses and bacteria.

43
Q

Golgi Vesicle

A

are often, referred to as the “traffic police” of the cell. They play a key role in sorting many of the cell’s proteins and membrane constituents, and in directing them to their proper destinations

44
Q

Vacuole

A

a space within a cell that is empty of cytoplasm, lined with a membrane, and filled with fluid. Especially in protozoa, vacuoles are cytoplasmic organs (organelles), performing functions such as storage, ingestion, digestion, excretion, and expulsion of excess water.

45
Q

Peroxisome

A

a small organelle present in the cytoplasm of many cells, which contains the reducing enzyme catalase and usually some oxidases.

46
Q

Secretory Vesicle

A

is a vesicle that mediates the vesicular transport of cargo - e.g. hormones or neurotransmitters - from an organelle to specific sites at the cell membrane, where it docks and fuses to release its content.

47
Q

Microfiliment

A

assist with cell movement and are made of a protein called actin. Actin works with another protein called myosin to produce muscle movements, cell division, and cytoplasmic streaming. Microfilaments keep organelles in place within the cell.

48
Q

Centrosome

A

is a cellular structure involved in the process of cell division. Proteins called microtubules assemble into a spindle between the two centrosomes and help separate the replicated chromosomes into the daughter cells.

49
Q

Centriole

A

a minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and involved in the development of spindle fibers in cell division.

50
Q

Microtubule

A

a microscopic tubular structure present in numbers in the cytoplasm of cells, sometimes aggregating to form more complex structures.

Microtubules are very important in a number of cellular processes. They are involved in maintaining the structure of the cell and, together with microfilaments and intermediate filaments, they form the cytoskeleton. They also make up the internal structure of cilia and flagella.

51
Q

Intermediate Filament (IF)

A

provide mechanical support for the plasma membrane where it comes into contact with other cells or with the extracellular matrix. Unlike microfilaments and microtubules, intermediate filaments do not participate in cell motility.

52
Q

Extracellular Matrix (ECM)

A

is a three-dimensional network of extracellular macromolecules, such as collagen, enzymes, and glycoproteins, that provide structural and biochemical support to surrounding cells.

53
Q

Plasma Membrane

A

The plasma membrane, also called the cell membrane, is the membrane found in all cells that separates the interior of the cell from the outside environment. In bacterial and plant cells, a cell wall is attached to the plasma membrane on its outside surface.

54
Q

Mutations

A

is a change in a DNA sequence. Mutations can result from DNA copying mistakes made during cell division, exposure to ionizing radiation, exposure to chemicals called mutagens, or infection by viruses.

55
Q

Sexual Reproduction

A

the production of new living organisms by combining genetic information from two individuals of different types (sexes). In most higher organisms, one sex (male) produces a small motile gamete which travels to fuse with a larger stationary gamete produced by the other (female).

56
Q

Ecosystem = Biome

A

describes a single environment and every living (biotic) organism and non-living (abiotic) factor that is contained within it or characterizes it. An ecosystem embodies every aspect of a single habitat, including all interactions between its different elements.

57
Q

DNA Replication

A

is the process by which DNA makes a copy of itself during cell division.
(4) steps in DNA replication:
Step 1: Replication Fork Formation. Before DNA can be replicated, the double stranded helix molecule must be “unzipped” into two single strands.
Step 2: Primer Binding. The leading strand is the simplest to replicate.
Step 3: Elongation.
Step 4: Termination.

58
Q

Transcription

A

is the process by which the information in a strand of DNA is copied into a new molecule of messenger RNA (mRNA). DNA safely and stably stores genetic material in the nuclei of cells as a reference, or template.

59
Q

Translation

A

In molecular biology and genetics, translation is the process in which ribosomes in the cytoplasm or endoplasmic reticulum synthesize proteins after the process of transcription of DNA to RNA in the cell’s nucleus. The entire process is called gene expression.

60
Q

Gene Expression

A

is the process by which information from a gene is used in the synthesis of a functional gene product that enable to produce protein as the end product. These products are often proteins, but in non-protein-coding genes such as transfer RNA or small nuclear RNA genes, the product is a functional RNA.

61
Q

Mitosis

A

is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. The result is two genetically identical daughter nuclei. The rest of the cell may then continue to divide by cytokinesis to produce two daughter cells.

Mitosis involve (5) phases, based on the physical state of the chromosomes and spindle:
prophase, prometaphase, metaphase, anaphase, & telophase.
62
Q

Meiosis

A

is a special type of cell division of germ cells in sexually-reproducing organisms used to produce the gametes, such as sperm or egg cells. It involves two rounds of division that ultimately result in four cells with only one copy of each paternal and maternal chromosome.

In each round of division, cells go through
(4) stages:
prophase, metaphase, anaphase, & telophase.

Biology (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions