C2.1 HL only Flashcards
Cell signaling
the process by which cells communicate with each other and their environment to respond to stimuli
Ligand
a molecule that binds to a receptor, which is a protein molecule, to send signals within or between cells
Hormones
chemical substances that act like messenger molecules in the body
Neurotransmitters
chemical messengers that carry signals between nerve cells, muscles, and glands
Cytokines
small proteins that act as chemical messengers to regulate the immune system and other cells in the body
Calcium ions
positively charged ions that play a vital role in many biological processes
Receptor
a molecule or cell that binds to a specific substance and causes a reaction in the cell
target cells
a cell that is acted on selectively by a specific agent
binding site
a region on a molecule or cell surface where a chemical substance can attach
specificity
the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species
conformational change
a change in the shape of a molecule, often caused by environmental factors
Quorum
a cell-to-cell communication process that allows bacteria to sense their cell density and the composition of nearby species
Bioluminescence
the ability of a living organism to produce and emit light through a chemical reaction
Vibrio fischeri
a bioluminescent, rod-shaped, Gram-negative marine bacterium that can live independently or in a symbiotic relationship with certain fish and squid
bobtail squids
small cephalopods that are related to cuttlefish and are known for their symbiotic relationship with luminous bacteria
autoinducing molecule
a signaling molecule thatenables detection and response to changes in the population density of bacterialcells
LuxR
a protein that regulates gene expression in Gram-negative bacteria through a quorum sensing (QS) system
luciferase catalase
the class of oxidative enzymes that produce bioluminescence
Pheromones
chemical signals that organisms release to communicate with other members of their species
Acetylcholine
a chemical messenger that acts as a neurotransmitter, carrying signals from the brain to the body’s cells
Cytokine storm
A severe immune reaction in which the body releases too many cytokines into the blood too quickly
synapse
a junction between two neurons that allows for the transmission of information
endocrine glands
organs that produce and release hormones into the bloodstream, where they travel to cells throughout the body
Amines
a class of organic compounds that contain a nitrogen atom with a lone pair and are derived from ammonia
Peptides
a short chain of amino acids that are linked together by peptide bonds
Steroids
Any of a group of lipids (fats) that have a certain chemical structure
Esters
organic compounds that are formed when an alcohol and an acid react, resulting in the loss of water molecules
Gasses
small gaseous molecules that function as neurotransmitters. This family of neurotransmitters consists of nitric oxide (NO), carbon monoxide
Local signaling
a type of cell communication that occurs when cells that are close together use signals to communicate with each other
Distant signaling
a type of cell communication where signaling molecules travel from one cell to a target cell that is far away
Transmembrane receptors
protein molecules that span the cell membrane and interact with external ligands to trigger intracellular responses
Ion channel linked receptors
cell-surface receptors that open and close ion channels in response to chemical signals
G-protein linked receptors
a large group of cell surface proteins that respond to a wide range of external signals and play a key role in many bodily functions
Enzyme linked receptors
proteins that act as both receptors and enzymes, and play a key role in cell growth, differentiation, and survival
Intracellular receptors
proteins found inside a cell that regulate gene expression and cellular functions
transcription factors
proteins that regulate gene activity by binding to DNA and other proteins
First messenger
an extracellular factor that binds to a cell’s surface receptor and initiates a response within the cell
Reception
the process of activating sensory receptors by stimuli, such as chemicals, temperature, or mechanical stimuli
Transduction
the process by which a virus transfers genetic material from one cell to another
secondary messenger
a small molecule or ion that relays signals from cell surface receptors to target proteins within the cell
signaling cascade
a series of chemical reactions that occur in a cell in response to a stimulus
Cyclic AMP
(cAMP) isa small, hydrophilic molecule that acts as a second messenger in cells, regulating many physiological processes
Response
the action of an organism in reaction to an internal or external stimulus
Impulse transmission
the process by which nerve impulses are sent from one neuron to another, allowing the body to react to stimuli
membrane potential
the difference in electrical potential between the inside and outside of a biological cell
electrochemical potential difference
the difference in energy between two points, such as inside and outside a cell
terminal bud
a bud located at the tip of a plant stem that is responsible for most of the plant’s growth
pre-synaptic cell
a neuron that sends information to another neuron at a synapse
Voltage-gated Ca2+ channels
transmembrane proteins that allow calcium ions to enter cells in response to changes in the cell’s membrane potential
exocytosis
the process by which a cell moves large molecules and waste out of the cell and into the extracellular space
ligand-gated Na+ channels
a type of ion channel that allows sodium ions to pass through the membrane of a cell when activated by a ligand
G-protein-coupled receptors
proteins on the surface of cells that receive messages from the environment and transmit signals within the cell
GTP
Guanosine Triphosphate(GTP) isa molecule that is involved in various cellular processes and serves as an energy source for certain biochemical reactions in the brain
“fight or flight” response
an automatic physiological reaction to a perceived threat that prepares the body to either fight or flee
Epinephrine
a hormone and neurotransmitter that plays a key role in the body’s fight-or-flight response
adrenal glands
small, triangular-shaped organs that sit on top of each kidney and produce hormones that regulate many important bodily functions
adrenergic receptor
cell surface proteins that bind to catecholamines like epinephrine and norepinephrine, and mediate the actions of the sympathetic nervous system
adenylate cyclase
an enzyme that converts adenosine triphosphate (ATP) into cyclic adenosine monophosphate (cAMP)
Insulin
a hormone that regulates the amount of glucose (sugar) in the blood and controls how the body uses energy
pancreas
a glandular organ in the abdomen that produces enzymes and hormones to aid in digestion and blood sugar regulation
Negative feedback system
a control mechanism that helps maintain a steady state, or homeostasis, by returning conditions to a set point when they change
Receptor tyrosine kinase
a protein found on the surface of cells that plays a key role in many cell functions, including cell division, metabolism, and survival
tyrosine
a nonessential amino acid that plays a key role in many biological processes
pancreatic beta cells
endocrine cells in the pancreas that produce and release insulin, a hormone that controls blood sugar levels
glucose-transport proteins
membrane proteins that help glucose molecules enter cells
facilitated diffusion
a passive transport process that moves molecules across a cell membrane from a higher concentration to a lower concentration without using energy
hormone-receptor complex
a molecule or complex of molecules inside of or on the surface of a cell that binds its hormone resulting in a molecular change, which initiates a characteristic response or group of responses
Testosterone
a hormone that plays a key role in the development and maintenance of male sex characteristics and other bodily functions
Serum Response Factor gene
a transcription factor that regulates many genes involved in cellular activities, including:cell proliferation, cell migration, differentiation, angiogenesis, and apoptosis
Oestradiol
a steroid hormone that plays a key role in the female reproductive system and other bodily functions
ovarian cycle
a series of events that occur in the ovaries to prepare an egg for fertilization and reproduction
hypothalamus
a part of the brain that coordinates the endocrine system and maintains a stable internal state called homeostasis
ovaries
the female reproductive glands that produce eggs and hormones
Gonadotropin-releasing hormone
a hormone that plays a vital role in sexual maturity, fertility, and sex drive
puberty
the biological process of physical and hormonal changes that mark the transition from childhood to adulthood
ovulation
the biological process of releasing an egg from an ovary during the menstrual cycle
luteinizing hormone
a hormone that plays a role in sexual development and fertility in both men and women
Progesterone
a steroid hormone that plays a vital role in the reproductive system, including menstruation, pregnancy, and sperm production
uterine cycle
a series of changes that occur in the uterus each month to prepare for pregnancy
endometrium
the inner lining of the uterus, made up of glandular cells that produce secretions
menstruation
the shedding of the lining of the uterus, or endometrium, that occurs when pregnancy doesn’t happen
Insulin-like Growth Factor gene
genes that encode proteins that promote growth and development
Positive feedback
a feedback loop where a change in a given direction causes additional change in the same direction
homeostasis
the process by which living organisms maintain a stable internal environment while adjusting to external changes
Cyclin-CDK
families of proteins that regulate the cell cycle and other cellular processes
