Biology Lecture exam #2 Flashcards
What are four types of receptors?
Ion Channel
G protein
Enzyme
Intracellular
What are four types of signals?
Neurotransmitters
Hormones
Direct Contact
Paracrine
Ion Channel
protein in a cell membrane that allows ions to pass through it
Hormones
Gland produced chemical messengers that travel through the bloodstream to reach target cells and trigger response
Neurotransmitters
Released by neutrons to activate other neutrons, muscles, or glands.
Direct contact
Other signals are sent from one cell to another cell.
Paracrine
Sent by diffusion through intercellular fluid to NEARBY
cells.
G protein
Large family of proteins that loop back and forth through the plasma membrane 7 times.
When signaling ligand bind to a receptor, the ligand receptors complex associates w/ g protein. This causes GDP to be replace by GTP and one subunit separate from the other two subunits.
Enzyme receptors
A transmembrane receptor, where the binding of an extracellular ligand causes enzymatic activity on the intracellular side.
When a ligand connects to receptor it because active and activates ATP when then gets replaced by ADP
Intracellular receptors
Recognize and bind ligands to modify mRNA and protein synthesis
Adenylyl Cyclase
Enzyme responsible for catalyzing the conversion of ATP to cyclic AMP (cAMP).
How does the amphipathic nature of phospholipids lend itself to membrane formation?
The hydrophobic tail connect together while the hydrophilic head attract towards the water, which binds together into Long chains.
Why is cholesterol crucial to membrane integrity?
Cholesterol is crucial because it holds the membrane together and helps the membrane from being stiff and ridgid while also gives it its flexibility.
Target cell
A cell or tissue with receptors that bind a hormone
Receptors
large proteins or glycoproteins that bind with signaling molecules
Mitochondrion
Power plant of cell
Convert energy into forms that can be used by cells
Found in animal cells
ribosomes
small complexes of ribonucleic acid (RNA) and protein that synthesize polypeptides
Cytoplasm/Cytosol
parts of a cell outside the nucleus
Smooth ER
involved in lipid metabolism
has a tubular appearance, and its membrane surfaces appear smooth
Rough ER
ribosomes mattached to the cytosolic surface
Golgi complex
Distribution center
Cell organelle that processes ER/proteins and lipids for use inside and outside the cell
lysosomes
recycling center of the cell
Chloroplasts
Power house for plant cells
An organelle within the cells of plants and certain algae that is the site of photosynthesis
Plasma Membrane
City gates
The surface around animal cells
Nucleus
City hall; Center of the cell
Stores DNA molecules in the form of chromosomes.
Cell wall
The outer shell of a plant cell. Similar to the plasma membrane in plant cells
Allows the cell to survive in harsh environments without rupturing
Central Vascle
Large water container that storages water for the plant
What is a slow acting cell signal that dispersed through the body via the blood stream?
Hormones
Second messengers
Cyclic AMP (cAMP)
A membrane receptor that allows sodium to pass through the membrane
Ion channel linked receptor
A enzyme that phosphorylate target molecules
Kinases
Kinases
Adds phosphate groups from ATP
Phosphorylase
Adds free phosphate groups
ATP synthase
adds phosphate to ADP produces ATP
A receptor that utilizes GTP as part of the signal transduction process
G-Protein
Gleevec
Cancer drug that stops cancer cells from multiplying
Chromosomes
DNA that has been pushed and squashed together
What would occur if a steroid hormone binds to and activates its receptor
nucleosomes unwind
Plastids
Found in plant cells
double-membrane organelles
ex: chloroplast (green food for plant) and amyloplast (starch in potatoes)
Hypertonic
Larger amount of solute compared to water (cell shrinks up due to water excerting out)
Hypotonic
Larger amount of water compared to solute (cell swells to the point of potential rupture)
Isotonis
Equal amount of water and solute (cell stays the same)
Facilitated diffusion
diffusion down concertration gradient
Active transport
moves ions or molecules against the concertration gradient
Symports
a membrane protein that transports two different molecules across a cell membrane in the SAME DIRECTION at the same time
Surface to volume ratio
The ratio between the surface area of a cell or organism and its volume.
Cells can’t be larger than what they are due to oxygen not being abkt to get through the winter cell fast enough if its too big
Prokaryotic
Typically smaller in size
Contains no nucleus, only DNA and ribosomes
Contains a fallgella
Oldest cell
eukaryotic
Typicaller large in size
Contains nucleus and organelles
Found in animals and humans
Flagellum
help unicellular and small multicellular organisms move through a watery environment.
Cilium
Cells use cilia to move liquids and particles across the cell surface
glycocalyx
Known as “cell coat” due to it surrounding the cell.
formed by polysaccharide side chains of proteins and lipids that are part of the plasma membrane.
nucleolus
structure found in the cell’s nucleus whose primary function is to produce and assemble the cell’s ribosomes
Cytoskeleton
The frame work of the cell
It provides structural support so the cell can move around and be protected from outside soruces
Integral Protein
A protein found in the a membrane
(cell/organelle) embedded FULLY THROUGH
peripheral protein
A protein found in the a membrane
(cell/organelle) embedded in the OUTTER LAYER
glycoprotein
protein with shorter, branched carbohydrate chains known as oligosaccharides
glycolipid
lipids with a carbohydrate attached by a glycosidic (covalent) bond.
endocytosis
Helps I gets food particles past the hydrophobic plasama membrane and into the cell
What are different types of endocytosis?
Pinocytosis
Phagocytosis
Receptor-mediated endocytosis
Pinocytosis
The process of endocytosis but when the material is liquid
Phagocytosis
The process of endocytosis but when the material is solid
Receptors-mediated endocytosis
A process by which cells absorb metabolites, hormomes, and proteins.
Extocytosis
Reverse endocytosis, results in the discharge of materials
Antiports
a membrane protein that moves two or more molecules in OPPOSITE DIRECTION across a cell membrane
Concentration gradient
slope of sort from a high concentration to a low concentration
Crenation
a animal cell shrinks and develops a scalloped and notched appearance due to the water loss
Playsmosis
a plant cell shrinks and develops a scalloped and notched appearance due to the water loss
Osmosis
Diffusion of water
Diffusion
Diffusion of solute
Solute
Sugar, salt, etc
Solvent
Water
