Exam 1 Flashcards
What domains are living organisms classified under?
Archaea, bacteria, and eukaryotes
What are eukaryotes?
Single or multi-cellular organisms with nuclei
What are the characteristics of animals?
Multicellular, breathe oxygen and have mitochondria, motile and heterotrophic, sexual reproduction, advanced sensory and circulatory systems, and development begins with the formation of a blastula
How many species are there in the animal kingdom?
1.5 million
What is animal anatomy?
The study of animal body structures
What is animal physiology?
The study of normal animal functions
What is homeostasis?
Maintaining a stable physiology or equilibrium in a constantly changing environment
What are the phases from zygote to blastula?
Zygote, 2-cell stage, 4-cell stage, morula, and blastula
What is the ectoderm?
The epidermis of skin and its derivatives (sweat glands, hair follicles), includes the nervous system
What is the mesoderm?
Notochord, skeletal system, muscles, circulatory and lymphatic system, reproductive system, dermis of skin, lining of body cavity, and adrenal cortex
What is the endoderm?
Epithelial lining of the digestive tract, epithelial lining of the respiratory system, lining of the urethra, bladder, and reproductive system, the liver, the pancreas, the thymus, and the thyroid and parathyroid glands
What makes up the cell lipid barrier?
Phospholipids, cholesterol, and proteins
What is contained within the cell cytoplasm?
Organelles, structural proteins, intracellular signaling, and glycolysis
What happens within the nucleus?
DNA and genetic code are stored, mRNA transcription
What happens within the mitochondria?
Oxidative phosphorylation and steroid production
What happens within the endoplasmic reticulum?
Ribosome are stored, mRNA translation, and calcium storage
What happen in the golgi apparatus?
Protein processing and packaging
What are vesicles or granules?
Contains materials for cell bulk transport into and out of the cell
What is exocytosis?
Material is released into extracellular space by budding of small vesicles from the cell membrane
What is endocytosis-pinocytosis?
Absorption of extracellular components into the cell by budding of small vesicles from the cell membrane
What is endocytosis-phagocytosis?
Ingestion of large material, including other cells, by specialized cells
What are microvilli?
Membrane extensions that increase cell surface area for secretion and absorption, particularly for epithelial cells
What are cilia?
Large membrane-protein extensions that can use ATP to beat or move. Used by the cell to move contents, sense vibrations, or fluid movement in the animal body.
What is the animal cell chemical composition?
Water, protein, lipid, carbohydrates, and inorganic solutes
How much water is in cells?
60%
Where do animals get amino acids and what are they used for?
From diet or synthesized in cell, can be used as a form of energy.
What are proteins?
Polypeptides that form 3D structures, function affected by pH and temperature
What are the functions of proteins?
Enzymes, hormones, receptors, cell structure, and transport
What are monosaccharides?
Simple sugars, Glucose is the most prevalent in the body
What are two examples of disaccharides?
Lactose and maltose
What is glycogen and where is it produced?
Long chains of glucose, produced in the liver and muscle
What are starch and cellulose?
Long chains of glucose found in plants and used by plants for energy and structure.
How many deoxyribose units are in each cell?
12 billion
What are inorganic solutes?
Ions that makeup 1% of the cell. ex: potassium, sodium, chloride, phosphate, and bicarbonate
What is an electrolyte?
A molecule that dissolves into individual ions in a solution
What are fatty acids?
Chains of carbon and hydrogen (hydrocarbons)
What are properties of fatty acids?
They can form triglycerides, and they can be modified into ligands/hormones.
What are triglycerides?
Glycerol + 3 fatty acids. Stored as fat and used for energy
What are phospholipids and where are they found?
Phosphate group + 2 fatty acids. Found in the cell, nuclear, and mitochondrial membranes
What is cholesterol?
A component of the cell membrane, can be converted to steroids.
What are the functions of membrane proteins?
Cell adhesion and transport, cell communication and enzyme activity, structure, and cell recognition by immune cells.
What are desmosomes?
Proteins that cause cell adherence
What are tight junctions?
Proteins that help form a tight barrier. important for epithelial cells.
What are gap junctions?
Proteins that aid in cell-to-cell communication. important for smooth and cardiac muscle synchronous contraction.
How to gap junctions work?
Connexin proteins form a passageway between two cells for molecule sharing and transport
What is a chemical gradient?
When the concentration of a molecule or solute is greater on one side of the membrane.
What is an electrical gradient?
When electrical charges are separates by the cell membrane.
What is an electrochemical gradient?
When a molecule or solute has both an electrical and chemical gradient.
What does the animal cell use electrochemical gradients for?
To do work
How do molecules diffuse?
From an area of high concentration to low concentration
What is the charge of an animal cell?
Negative
What is osmosis?
The movement of water across a permeable membrane toward an are of lower water concentration and a greater concentration of solutes.
What is an isotonic solution?
Having the same solute or osmotic pressure inside and outside the cell. This is normally 300 mOsm
What is a hypotonic solution?
When there is a higher solute concentration inside the cell, and a lower concentration outside.
What is a hypertonic solution?
When the solute concentration outside the cell is higher than the inside of the cell.
What is unassisted membrane transport?
Passive transport
What is assisted membrane transport?
Membrane proteins assist and control the movement of molecules across the cell membrane
What is passive diffusion?
Diffusion driven by chemical gradients, generally small, uncharged molecules. ex: oxygen, carbon dioxide, and water.
How is assisted membrane transport achieved?
With the help of cell membrane transporters called channels or carriers. The electrochemical gradient still drives diffusion. Some carriers use ATP to drive molecules against the gradient.
What are channels?
Proteins that transport ions such as Na+, K+, Ca+, Cl-, or water (passive transport).
What are leak channels?
Channels that are always open
What are voltage gated channels?
Channels that open in response to change in the cell membrane electrical charge. Can also be activated by physical or chemical stimuli.
How do molecules always flow?
Down an electrochemical gradient
What are aquaporin channels?
Water channels that transport billions of water molecules per second into the cell. Mammals have 13 different types.
What are carriers?
Proteins that transport molecules across the cell membrane using “flip-flop “activity.
What is a symporter?
A carrier that transports different molecules across the membrane in the same direction.
What is an antiporter
A carrier that transports different molecules across the membrane in the opposite direction.
What is facilitated transport?
When a molecules flows down a gradient and does not require ATP
What is active transport?
A molecules is pumped up a gradient and requires ATP
What is primary active transport?
The carrier uses ATP directly to transport the molecule.
What is the Sodium-Potassium ATPase pump?
A major animal cell primary active transporter. 3 Na+ out and 2 K+ into the cell, against gradients. Helps to establish a negative charge inside the cell membrane and maintain osmotic equilibrium.
What is secondary active transport?
When ATP is required to transport the molecule but ATP is not directly used by the carrier.
What does the rate of transport depend on?
The number of carriers present in the cell membrane
What is membrane potential?
The difference in electrical charge across the cell membrane in millivolts
What is the resting membrane potential?
The resting charge along the inside of the cell membrane when the cell is at “rest”
What is threshold potential?
The minimal membrane charge that can trigger an irreversible flow of positive charged ions into the cell through voltage gated channels
What is action potential?
Rapid, short lived, changes in membrane charge so that the inside of the cell becomes more positive (depolarization).
What are action potentials triggered by?
Physical, chemical, or electrical stimuli.
What does action potential allow?
It allows the cell to do work such as contract or release ligands/hormones or neurotransmitters.
What is action potential essential for?
Muscle and nervous tissue function
What process/steps happens during action potential?
- Resting potential
- Voltage gated Na+ channels open
- Na+ rapidly enters cell
- At peak action potential, Na+ channels close and voltage gated K+ channels open.
- K+ leaves cell, causing repolarization to resting potential
- Na+ channels are closed but capable of reopening
- Further movement of K+ briefly hyperpolarizes the cell membrane
- K+ channels close, and the membrane returns to resting potential
What is intracellular signaling?
Signaling that occurs between cells by direct cell-to-cell contact (gap junctions and juxtracrine signaling)
What is extracellular signaling?
When signaling molecules are secreted into the extracellular space for cell-to-cell communication (paracrine and autocrine signaling)
What is a neurotransmitter?
A ligand that is secreted by a neuron or signals to a neuron (paracrine signaling).
What is endocrine signaling?
A ligand is secreted into the blood vessels for long-distance cell-to-cell communication
What is a ligand called when it is secreted into the blood?
A hormone
What is neuroendocrine signaling?
A ligand is secreted by a neuron into the blood.
What is a pheromone?
A ligand that is secreted outside the animal body for communication with a different animal.
Where are receptors for large ligands found?
In the cell membrane
What do ligands activate?
Intracellular enzyme cascades
What is the most common type of cell membrane receptor?
7-membrane domain receptor (7TMDR)
Where are receptors for small or lipophilic ligands such as steroids found?
Inside the cell cytoplasm (may take hours or days)
What is saturation?
When receptors become saturated
What is specificity?
Receptors typically bind to a specific molecule
What are antagonists of ligands?
A molecule that blocks the function of a ligand.
What are agonists of ligands?
A molecule that contributes to the function of the ligand. Usually involves binding of a molecule to the ligands receptor, activating it.
What are the types of animal muscle?
Skeletal, smooth, and cardiac
What are the functions of skeletal muscle?
Moves and stabilizes animal limbs and joints, contraction is consciously or voluntarily controlled (mostly), striated with organized proteins for contraction, stores glucose, helps animal breathe, helps return blood to the heart, and generates heat.