Term
| What is the most common form that fixed nitrogen enters plants? |
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Definition
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|
Term
| Where does a plant store fixed nitrogen? |
|
Definition
|
|
Term
| How does a plant transport fixed nitrogen? |
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Definition
|
|
Term
| Briefly describe nitrogen fixation. |
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Definition
| Atmospheric nitrogen (N2) combines with hydrogen (H) to give NH3, fixed nitrogen. |
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Term
| What is the main way nitrogen can be fixed biologically? |
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Definition
| Most biological nitrogen fixation occurs by way of certain prokaryotes such as cyanobacteria and other nonphotosynthetic bacteria. All nitrogen-fixing prokaryotes utilize large amounts of ATP and nitrogenase to fix nitrogen. |
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Term
| What are some plant adaptations that allow for increased nutrient supply? |
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Definition
Highly branched roots
More or longer root hairs
Fungal symbiotic associations
Bacterial symbiotic associations
Capture of animals (in carnivorous plants)
Parasitic associations |
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Term
| Explain how mycorhizzal associations are helpful to a plant. |
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Definition
Fungi live within root tissues or envelop root surfaces.
The fungi obtains its organic food from the plant while supplying water and mineral to the plant, making it mutually beneficial for the plant and the fungi. The fungi provides the plant with a very efficient way to harvest water and minerals (especially phosphorus) from a larger volume of soil. |
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Term
| Explain how bacterial symbiotic associations are helpful. |
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Definition
| Some bacterial symbiotes live within plant cells or tissues. In this case, the plant provides organic nutrients to the bacteria and the bacteria supplies fixed nitrogen for the plant. The amount of fixed nitrogen provided by the bacteria is more than the plant could acquire from the soil. |
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Term
| Briefly describe the materials transported by xylem and phloem. |
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Definition
Xylem transports water and dissolved minerals
Phloem transports dissolved organic substances |
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Term
| What does the water content of cells depend on? |
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Definition
Osmosis
Turgor pressure (hydrostatic pressure that increases as water enters plant cells) |
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Term
| What does it mean when a cell is "plasmolyzed"? |
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Definition
| A cell becomes “plasmolyzed” when it has lost so much water that the turgor pressure lost. |
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Term
| What does it mean when a cell is "turgid"? |
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Definition
| A plant is "turgid" when it is very full of water and the plasma membrane pushes up against cell wall. |
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Term
| What are the three types of tissue-level transport? |
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Definition
Transmembrane transport
Symplastic transport
Apoplastic transport |
|
|
Term
| Describe transmembrane transport. |
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Definition
| The material from one cell is transported into the intercellular space and then imported into the adjacent cell. Thus it is transported from cell to cell to its destination. |
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Term
| Describe symplastic transport. |
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Definition
| Material moves from the cytosol of one cell to the cytosol of an adjacent cell via plasmodesmata (microscopic channels). Material moves through plasmodesmata by diffusion. |
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Term
| Describe apoplastic transport. |
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Definition
| Material is exported through the cell wall and then transported in the spaces between cells. Only used in short distance transport. |
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Term
| What are casparian strips? |
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Definition
| Casparian strips are barriers that prevent apoplastic transport into root vascular tissues (only symplastic movements allowed because symplastic is more selective than apoplastic). |
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Term
| Explain how material is transported into the endodermis. |
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Definition
| The root endodermis functions as a molecular filter that allows the passage of beneficial solutes that have entered from the symplast or have been specifically transported into endodermal cytosol through specific transport channels. The endodermal plasma membrane possesses specific channels and transporters for essential mineral nutrients. |
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Term
| What specialized cells does xylem contain? |
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Definition
Parenchyma: cells are alive but not directly involved in long-distance transport
Thick-walled supportive fibers: may be alive or dead at maturity; provide structural support
Tracheids and vessel elements: specialized water-conducting cells and are always dead and empty of cytosol/cytoplasm when mature (gymnosperms contain only tracheids)
Tracheids: Long and narrow with slanted end walls; Lignin-containing (water-impermeable, secondary wall); Pits – nonlignified holes allow water to flow from one tracheid to another
Vessels and vessel elements: vessel elements are aligned in pipeline-like files known as vessels; they give greater capacity for bulk flow to flowering plants |
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Term
| Explain how stomatal movements help reduce transpirational water loss. |
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Definition
Guard cells close to conserve water when it is not needed for photosynthesis. Blue light stimulates active guard cell ion uptake, causing water to flow in, the cell to expand and stomata to opens. At night, ions are pumped out, causing the cell to deflate and the stomata to close.
*ABA can also close stomata during the day |
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Term
| What stimulates the creation of an abscission zone in order for a leaf to drop? |
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Definition
|
|
Term
| What cells compose phloem? |
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Definition
| Phloem is composed of supporting fibers, parenchyma cells, sieve-tube elements (cells), and adjacent companion cells. |
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Term
| Explain sieve-tube elements and adjacent companion cells |
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Definition
| A sieve-tube element loses its nucleus and most of the cytoplasm to reduce obstruction to bulk flow. The companion cell supplies mRNA and proteins to sieve tube element via plasmodesmata. |
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Term
| What are the 2 multicellular life cycle stages of a plant? |
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Definition
Diploid, spore-producing sporophyte: produces spores by meiosis
Haploid, gamete-producing gametophyte: produces gametes by mitosis |
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Term
| What produces a flower's organs? |
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Definition
|
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Term
| What is the purpose of a flower's sepal? |
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Definition
| Protect unopened flower bud |
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|
Term
| What is the function of flower petals? |
|
Definition
| The attraction of pollinators |
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Term
| What is the function of a flower's stamen? |
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Definition
| Produce male gametophyte and foster their early development |
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Term
| What is the function of a flower's pistil? |
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Definition
| Produce, enclose, and nurture female gametophytes and mature male gametophytes |
|
|
Term
| Explain how a mature gametophyte is developed. |
|
Definition
When pollen grains land on stigma, stigma allows only appropriate genotype to germinate
Pollen tube grows through micropyle and delivers sperm to female gametophyte
Results in double fertilization |
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Term
| What is the endosperm of a flower and what is its function? |
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Definition
Endosperm develops as a nutritive tissue, usually triploid chromosome number
Supplies nutritional needs for developing embryo and often seedling
Rich in protein, lipid, carbohydrate, vitamins and minerals
Nutrients in endosperm comes from parent sporophyte by apoplastic transport
Eudicots store organic food inside cotyledons (mature seeds contain little to no endosperm)
Monocots retain considerable endosperm in the mature seed (only part incorporated into the single cotyledon) |
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|
Term
|
Definition
| A young, multicellular, diploid sporophyte |
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Term
|
Definition
| Specialized cells of a specific type organized together to perform a specific function. |
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Term
| What are the four main categories of animal tissue? |
|
Definition
Muscle tissue
Nervous tissue
Epithelial tissue
Connective tissue |
|
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Term
| What are the three types of muscle tissues in animals? |
|
Definition
Skeletal – attached to bone or exoskeleton for locomotion, voluntary control
Smooth – surrounds hollow tubes and cavities for propulsion of contents, involuntary control
Cardiac – only in the heart, involuntary control |
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|
Term
| What is the role of nervous tissue? |
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Definition
| Initiate and conduct electrical signals from one part of the animal’s body to another. |
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|
Term
| What is included in the category "connective tissue?" |
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Definition
| Blood, adipose (fat), bone, cartilage, loose and dense connective tissue |
|
|
Term
| What are the main functions of connective tissues? |
|
Definition
Provides scaffold for attachment
Protects and cushions
Mechanical strength
Transmit mechanical forces |
|
|
Term
| What is the term for the fluid in an open circulatory system? |
|
Definition
|
|
Term
|
Definition
| Any substance consumed by an animal that is needed for survival, growth, development, tissue repair, or reproduction |
|
|
Term
| What are nutrients used for? |
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Definition
| Nutrients may be used to make ATP, as chemical building blocks (amino acids, sugars, fatty acids, nucleotides), or as cofactors/coenzymes (vitamin an mineral nutrients) |
|
|
Term
| What is ATP energy used for? |
|
Definition
Transport work
Mechanical work
Chemical work |
|
|
Term
| What are the 5 categories of organic food molecules that animals need for complete nutrition? |
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Definition
Carbohydrates
Proteins
Lipids
Nucleic acids
Vitamins |
|
|
Term
| What are essential nutrients? |
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Definition
| Certain compounds that an animal needs that cannot be synthesized from any ingested or stored precursor molecule |
|
|
Term
| What are the 4 groups of essential nutrients? |
|
Definition
Essential amino acids
Essential fatty acids
Essential Minerals
Essential Vitamins |
|
|
Term
| What are the 8 amino acids needed by many animals? |
|
Definition
| Isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine |
|
|
Term
| What are essential fatty acids needed for? |
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Definition
| Building fats, phospholipids, and steroid hormones |
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Term
| Compare the quantities at which animals need mineral micronutrients and mineral macronutrients. |
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Definition
Mineral micronutrients needed at less than 1-2 mg/day
Mineral macronutrients needed at more than 10mg/day |
|
|
Term
| What are mineral macronutrients needed for? |
|
Definition
energy metabolism,
body structure (bones)
membrane transport
electrical impulses in the nervous system. |
|
|
Term
| What are some important mineral macronutrients for humans? |
|
Definition
Calcium
Phosphorus
Magnesium
Sodium
Potassium
Iron
Zinc |
|
|
Term
| What are some important mineral micronutrients for humans? |
|
Definition
Cobalt
Copper
Iodine
Arsenic
Silicon
Selenium
Manganese
Molybdenum |
|
|
Term
| What are vitamins used as? |
|
Definition
|
|
Term
| Explain intercellular digestion. |
|
Definition
Only found in very simple invertebrate animals (sponges)
Tiny bits of food are phagocytosed
Food molecules broken down by enzymes in intracellular compartments (lysosomes) |
|
|
Term
| What some animals that digest food via a gastrovascular cavity? |
|
Definition
Cnidarians (Hydra, Jellyfish, Anemones)
Platyhelminthes (flatworms) |
|
|
Term
| How does saliva aid digestion? |
|
Definition
Released by salivary glands
Moistens and lubricates food to facilitate swallowing
Dissolves food particles to facilitate taste and increase accessibility to digestive enzymes
Lysozyme enzyme in saliva kills ingested bacteria
Initiates digestion of polysaccharides with salivary amylase enzyme |
|
|
Term
| What is the role of the pharynx? |
|
Definition
| The pharynx regulates the movement of food into the esophagus. |
|
|
Term
| What is the role of the esophagus? |
|
Definition
| The esophagus transmits food from the pharynx to the stomach. |
|
|
Term
| What is a "crop" and what animals have it? |
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Definition
| A "crop" stores and softens food. It is found in birds and many invertebrates. |
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|
Term
| What is secreted by the "gastric pits"? |
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Definition
| Hydrochloric acid and pepsinogen |
|
|
Term
| What hydrochloric acid's role in digestion? |
|
Definition
| Kills microbes and dissolves particulate matter |
|
|
Term
|
Definition
| Pepsinogen is the inactive form of pepsin, which initiates protein digestion. |
|
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Term
| What are the 3 pouches of the forestomach in a ruminant herbivore? |
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Definition
Rumen and reticulum – contain cellulose digesting microbes
Omasum – absorbs some of the water and salts from food |
|
|
Term
| What is the "abomasum" in a ruminant herbivore? |
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Definition
| The abomasum is the "true stomach" – eventually food, microbes and by-products of microbial digestion enter this structure. It contains digestive acid and proteolytic enzymes. |
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|
Term
| Is the small intestine longer in a herbivore or in a carnivore? |
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Definition
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|
Term
| Describe the lining of the small intestine. |
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Definition
| The intestinal mucosa (internal surface) is folded and covered with finger like projections called vlli. Each villus is also covered in microvilli, which increase the surface area of the epithelium by 600-fold. |
|
|
Term
| What does the pancreas do? |
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Definition
| Secretes protein, carbohydrate, and fat digestive enzymes and bicarbonate ion rich fluid, released into small intestine. |
|
|
Term
| What is the function of bicarbonate ion rich fluid? |
|
Definition
| Neutralizes acidic stomach chyme as it enters small intestine |
|
|
Term
|
Definition
| Produces bile. Bile contains bicarbonate ions (neutralize acids), bile salts (emulsify fat). |
|
|
Term
| What does the gall bladder do? |
|
Definition
|
|
Term
| What is the main function of the large intestine? |
|
Definition
| To store and concentrate fecal matter and absorb some salt and water. |
|
|
Term
| Most ingested carbohydrates are... |
|
Definition
| Carbohydrates are starch and cellulose with some monosaccharides and disaccharides |
|
|
Term
| What does salivary amylase do? |
|
Definition
| Initiates the digestion of starches. |
|
|
Term
| Explain how carbohydrates are digested. |
|
Definition
Digestion begins with salivary amylase in the mouth.
It is completed in the small intestine by pancreatic amylase and intestinal disaccharidases. |
|
|
Term
| Explain how proteins are digested. |
|
Definition
Initiated by pepsin in the stomach
Pancreas secretes trypsin and chymotrypsin
Inactive “zymogens” activated in small intestine
Small intestine enzymes complete protein digestion to dipeptides or amino acids
Transported into intestinal cells by secondary active transport, then into blood stream |
|
|
Term
| In what form do most lipids enter the body? |
|
Definition
|
|
Term
| Where are lipids digested? |
|
Definition
|
|
Term
| Explain the process of lipid digestion. |
|
Definition
In the small intestine, bile salts from liver/gall bladder emulsify fat into small droplets with increased surface area for digestion. Pancreatic lipase then breaks down triglycerides by clipping fatty acids off of glycerol backbone, producing free fatty acids and monoglycerides.
Bile salts, fatty acids and monoglycerides form tiny micelles. Fatty acids and monoglycerides diffuse from these micelles and diffuse into epithelial cells. Triglycerides reform inside intestinal cells. Triglycerides and other lipids are assembled into chylomicrons;
chylomicrons are released by exocytosis from epithelial cells, then transmitted into lacteals. Will enter into general blood circulation from lymph fluid. |
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|
Term
| What animal phyla does not have a nervous system? |
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Definition
|
|
Term
| What are the two types of cells in the nervous system? |
|
Definition
Neurons
Glial cells (“glia”) |
|
|
Term
|
Definition
| Dendrites are extensions of a neuron's plasma membrane that may be single or branching that transmit incoming electrical signals toward cell body. |
|
|
Term
|
Definition
| Axons are extensions of a neuron's plasma membrane that send electrical signals propagating outward from cell body |
|
|
Term
| What are the 3 functional categories of neurons? |
|
Definition
| Sensory neurons, motor neurons, and interneurons |
|
|
Term
| What type of cells make up the myelin sheath? |
|
Definition
| Glial cells: Oligodendrocytes (CNS) and Schwann cells (PNS) |
|
|
Term
|
Definition
| Glial cells that remove cellular debris |
|
|
Term
| What are the 3 factors contributing to membrane potential? |
|
Definition
1) Na+/K+ -ATPase (sodium-potassium pump
Transports 3 Na+ out for every 2 K+ moved in
2) Negatively charged molecules such as proteins more abundant inside cell
3) Ion specific channels allow passive diffusion of ions down concentration and charge gradients. |
|
|
Term
|
Definition
Depolarization is when the cell membrane potential becomes less negative (inside of cell less negative relative to surrounding environment.)
Typically occurs when gated channels open allowing Na+ to flow in and membrane potential becomes more positive |
|
|
Term
| What is hyperpolarization? |
|
Definition
Hyperpolarization occurs when the cell membrane becomes more polarized (cytoplasm of cell becomes more negative relative to surrounding environment.)
Occurs if K+ moves out of the cell making the interior of the cell less positive |
|
|
Term
| What is a "voltage-gated" ion channel? |
|
Definition
| Opens and closes in response to voltage changes |
|
|
Term
| What is a "ligand-gated" ion channel? |
|
Definition
| Open and close in response to ligands or chemicals |
|
|
Term
| What does the speed of conduction depend on? |
|
Definition
Axon diameter (broad axons provide less resistance and action potential moves faster)
Myelination (myelinated faster then unmyelinated) |
|
|
Term
|
Definition
| The junction where a nerve terminal meets a neuron, muscle cell, or gland |
|
|
Term
| What are the two types of synapses? |
|
Definition
|
|
Term
| What type of nervous system is found in cnidarians? |
|
Definition
| A nerve net: the simplest nervous system in which neurons connect to each other in a loose network |
|
|
Term
| What type of nervous system is found in Echinoderms? |
|
Definition
| Nerve ring around mouth connected to larger radial nerves extending to arms |
|
|
Term
| What type of nervous system is found in Platyheminthes? |
|
Definition
Dual nerve cords extend length of animal connected by transverse nerves
Two anterior ganglia (clusters of neurons)
Perform basic integration functions |
|
|
Term
|
Definition
| The central nervous system: the brain and spinal cord |
|
|
Term
|
Definition
| The peripheral nervous system: Neurons and axons of neurons outside the CNS (ganglia and peripheral nerves) |
|
|
Term
| What is an action potential triggered? |
|
Definition
| When the graded potential reaches the threshold (-50mV) |
|
|
Term
| In an action potential, is potassium or sodium released first? |
|
Definition
| K+ channels have a slightly slower opening time than Na+ channels |
|
|
Term
|
Definition
| Glial cells that provide metabolic support and protection |
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