Biology Flashcards
Active Transport
a type of cellular transport that requires energy (often in the form of ATP) to transport molecules or substances ‘against’ their concentration or electrochemical gradients.
Amino Acids
monomers of proteins
4 Macromolecules
-proteins
-lipids (fats, non-polar + hydrophobic)
-carbohydrates (sucrose, C + H2O, fruits, grains, ect.)
-nucleic acids (RNA and DNA, 5’ phosphate group, 3’ OH group)
Central Dogma
This theory states that genetic information, in all cells flows from DNA to RNA to proteins.
Facilitated Transport
transport that requires a channel or to move a molecule/substance across the membrane
Facilitated Passive Transport
when a molecule is moving down its gradient (no energy used) with the help of membrane proteins
Golgi Apparatus
a membranous organelle that helps process and package lipids, proteins, and carbohydrates in the cell. Important in protein-sorting.
Glycolic Linkage
the name of the bond that carbohydrate monomers through the process of dehydration synthesis.
Lysosome
an organelle that contains digestive enzymes for breaking down cellular parts and digesting viruses or bacteria that infect a cell
Non-polar
a covalent bond between two or more atoms in which the atoms have the same electronegativity and equal sharing of the shared electrons. Non-polar molecules are water insoluble
Nucleic Acid
a class of biological macromolecules made of nucleotides. Primarily used for ‘information storage’, such as DNA and RNA. Some nucleic acids are also used as for energy (ATP) and cell signaling.
Nucleotide
It is the monomer of nucleic acids. It is comprised of nitrogenous base (A, T, G, C in DNA and A, U, G, C in RNA) covalently bonded to a pentose sugar (ribose in NTP and deoxyribose in dNTP) which is bonded to phosphates.
Passive Transport
a type of cellular transport that does not require energy. Molecules or substances move ‘down’ their concentration or electrochemical gradients.
Peptide Bond
the name of the bond formed between amino acids to make a polypeptide. Peptide bonds are made through the process of dehydration synthesis.
Peripheral Membrane Protein
a protein that interacts with the plasma membrane, though does not span the plasma membrane.
Phosphodiester Bond
the name of the bond formed between adjacent nucleotides in nucleic acid. Phosophodiester are made through the process of dehydration synthesis.
Polar
a covalent bond between two or more atoms in which the atoms have different electronegativity and unequal sharing of the shared electrons. Polar molecules are water soluble
Transcription
Transcription is the process of making an RNA copy of a gene’s DNA sequence. RNA transcribed can be either coding such as messenger RNA
Translation
Translation is the process of translating the sequence of a messenger RNA (mRNA) molecule to a sequence of amino acids during protein synthesis. mRNA is read in a 5’ 3’ direction from the start codon till the translation machine encounters the stop codon.
Nucleotide
It is the monomer of nucleic acids
Gene expression
A process by which the genetic information in a DNA sequence (= gene) is turned into a functional product i.e. protein or noncoding RNA (i.e. rRNA, tRNA etc.). All cells types in our body have the SAME genes. But express different sets of genes. This accounts for the difference in their shapes, size and functions.
Promoter sequence
It is a regulatory sequence of the gene to which RNA polymerase enzyme binds to start transcription. This sequence is NOT transcribed.
Amino acids
monomers of proteins
Point mutation
A point mutation is when a single base pair is altered, deleted or inserted.
Nonsense mutation
A nonsense mutation is the substitution of a single base pair that leads to the appearance of a premature stop codon where previously there was a codon specifying an amino acid.
Missense mutation
A missense mutation is when the change of a single base pair causes the substitution of a different amino acid in the resulting protein.
Frame Mutation
A frameshift mutation is a type of mutation involving the insertion or deletion of a nucleotide in which the number of deleted base pairs is not divisible by three
Silent Mutation
A point mutation in the gene that does not change the amino acid sequence of the resulting protein
Cell Cycle
A cell cycle is a series of events that takes place in a cell as it grows and divides. A cell spends most of its time in what is called interphase (G1 -> S -> G2), and during this time it grows, replicates its chromosomes, and prepares for cell division. The cell then leaves interphase, undergoes mitosis ( M phase of cell cycle), and completes its division. The resulting cells, known as daughter cells, each enter their own interphase and begin a new round of the cell cycle.
Deoxyribonucleotides
monomers of DNA. Each monomer has a nucleotide base ( A, T, G and C) covalently bonded to deoxyribose sugar which is also bonded to a triphosphate.
DNA polymerase enzyme
It polymerizes the new strand of DNA by reading template DNA strand during replication. This is a primer dependent enzyme i.e. it can add complementary bases only to the 3’ end of a primer.
RNA primers
They are made by Primase enzyme. These are short RNA sequence complementary and anti-parallel to template DNA strand. They have 3’ end to which DNA polymerase adds dNTPs during DNA replication
Helicase
An enzyme that unwinds the DNA double helix during DNA replication
Primase
An enzyme that makes RNA primers in a cell. These primers are essential for DNA polymerase to start making a new strand of DNA.
RNAase
An enzyme that degrades RNA primers later during DNA replication
Ligase
An enzyme that stiches the two strands of DNA together to make them continuous.
DNA polymerase
DNA polymerases are the enzymes that replicate DNA in living cells. They do this by adding individual dNTPs to the 3’ end of a growing strand of DNA. The process uses a complementary, single strand of DNA as a template.
Allels
Different variants/ forms of a gene. In a somatic cell there are two alleles (maternal allele and paternal allele) of each gene. Gametes have only one allele (either maternal allele or paternal allele) of a gene.
Genotype
This is the combination of maternal and paternal allele of a gene. This dictates the trait or characteristic associated with that gene.
Phenotype
The trait or characteristic associated with a gene(s). This is regulated by the corresponding genotype.
Somatic cell
A cell that has a paternal and maternal copy of each chromosome i.e. it is diploid (Ploidy = 2n)
Gametes
A cell that has either a paternal or maternal copy of each chromosome i.e. it is haploid (Ploidy = n)
Poloidy
The total number of genomic DNA copies that a cell has i.e. n, 2n, 4n etc.
Homologous chromosomes
A pair of chromosomes made of maternal and paternal homologs. The homologs have the same location of a gene but the alleles of the gene at that location may be same or different
Sister Chromatid
These are two exactly similar copies of a paternal or maternal chromosome homolog. Sister chromatids have the same alleles of the genes.
Non siter chromatid
They come from homologous chromosomes , they are not identical and contain may contain same or different alleles of the same gene at the same location.
Genome
All the chromosomes in the nucleus of a cell makes our genome
Steps of Mitosis
Prophase: Nuclear membrane disintegrates, chromosomes start to shorten and thicken.
Metaphase: Chromosomes are shortest and thickest, they align at the center
Anaphase: Sister chromatids pulled apart to the two ends of a cell
Telophase: Nuclear membrane reforms and chromosomes become, thin and less distinct once again
Cytokinesis: Cell physically divides to form two daughter cells.
Mendels law of segregation
When two organisms’ mate to produce an F2 offspring, only one of the two alleles of a gene in an organism is distributed to each gamete (egg or sperm cell) that it makes, and the allocation of the gene copies is random. When an egg and a sperm join in fertilization, they form a new organism, whose genotype consists of the alleles contained in the gametes.
Monohybrid cross
A monohybrid cross is a breeding experiment between P generation (parental generation) organisms that differ in a single given trait and are true breeding or homozygous for alleles of the gene in question.
Fitness
the ability to survive to reproductive age and produce offsprings
Survival
ability of an organism or species to survive and thrive in its environment overcoming challenges
Adaption
an evolutionary process by which populations adapt to better suit there environment and habits
ΔF508 mutation
most common cystic fibrosis mutation causing a mutation in the CFTR gene
Cystic Fibrosis Transmembrane Conductance Regulator (CFTR)
the protein found in the plasma membranes of cells that regulated chloride/water balance in cells and tissues. The CFTR gene is mutated in patients with the genetic condition of cystic fibrosis.
Deleterious mutation
A change in the DNA sequence of a gene that causes a person to have or be at risk of developing a certain genetic disorder or disease, such as cancer. Deleterious mutations can be inherited from a parent or occur during a person’s lifetime.
Emergent Property
arise when the interaction of individual component produce new functions.
Extracellular Matrix
A large network of proteins and other molecules that surround, support, and give structure to cells and tissues in the body. The extracellular matrix helps cells attach to, and communicate with, nearby cells, and plays an important role in cell growth, cell movement, and other cell functions.
Gene pool
consists of all the alleles present in all individuals in a species.
Germ-line
having to do with cells of the reproductive system-sperm or oocytes (eggs).
Hemoglobin
A protein inside red blood cells that carries oxygen from the lungs to tissues and organs in the body and carries carbon dioxide back to the lungs.
Heterozygote Advantage
describes the situation in which the heterozygote genotype is selected for through the process of natural selection.
Natural Selection
an adaptive mechanism of evolution in which organisms better adapted to their environment tend to survive, produce more offspring, and pass their alleles onto offspring. Natural selection may have the following impact on the frequency of alleles in a population:
Positive Selection
increases the frequency of favorable allele
Negative Selection
decreases the frequency of a deleterious allele
Balancing Selection
keeps an allele at an intermediate frequency in the population
Neutral Mutation
a mutation that is neither advantageous or deleterious
Tissue
a group of cells that work together to preform a specific function
