BIOL211 Exam 2

What are essential nutrients?

molecules that an animal needs by cannot synthesize

What are essential amino acids?

20 required to build proteins; animals are unable to synthesize 10 out of the 20 needed

What are essential fatty acids?

required for cell plasma membranes

What are vitamins?

organic compounds required in small quantities; usually function as coenzymes

What are minerals?

simple inorganic nutrients required in small quantities; function as cofactors

What adaptations do herbivores make?

eat diverse set of plant species, compensatory consumption, extensive gut flora

What is ingestion?

taking food in

What is digestion?

breakdown of food into molecules small enough to digest

What is absorption?

taking monomers into circulatory system

What is elimination?

removing waste

What is an alimentary canal?

extracellular digestive tube with two openings

What is extracellular digestion?

digestion occurs outside of cells rather than from inside; breakdown of cell from out to in

What is a gastrovascular cavity?

extracellular digestive pouch with one opening where food is ingested and wastes are eliminated

What is intracellular digestion?

each cell engulfs food and uses lysosomes to start chemical breakdown

What is a crop?

a storage structure for ingested food

What is a gizzard?

a site of mechanical digestion accomplished by grinding food using ingested pebbles and grit

What is the function of the oral cavity?

mechanical breakdown

What glands are associated with the oral cavity?

salivary glands

What macromolecule is chemically digested in the oral cavity?

carbohydrates

Where does absorption occur in the digestive system?

jejunum and ileum of small intestine, large intestine

What is the function of the esophagus?

muscular tube that pushes food from pharynx to stomach through peristalsis

What is the function of the stomach?

store/release food into small intestine, initial chemical digestion of proteins

What macromolecule gets chemically digested in the stomach?

protein

What enzymes are released in the stomach?

pepsinogen/pepsin

What is the function of parietal cells?

releases H+ to form HCl which will activate pepsinogen

What is the function of chief cells?

releases pepsinogen

What is the function of the small intestine?

where most enzymatic hydrolysis occurs

What are the accessory glands of the duodenum?

liver, gallbladder, pancreas

What macromolecules are chemically digested in the duodenum?

carbohydrates, proteins, nucleic acids, lipids

What are villi?

finger shaped projections on the lining of large folds

What are microvilli?

microscopic projections within each villi

What is the function of the colon?

water absoprtion

What is the function of the cecum?

fermenting ingested material

What is the function of the rectum?

feces storage and elimination

What anatomical adaptations do herbivores make to their digestive system?

longer alimentary canals and pouches that house bacteria and protists that can break down cellulose

What are ruminants?

large herbivorous animals that have a four chambered stomach to increase efficiency of cellulose digestion

What is coprophagy?

consuming feces

What anatomical adaptations do frugivores make to their digestive system?

longer intestines, enlarged liver for detoxifying, reduced gizzard

What is an open circulatory system?

circulatory fluid drains directly into body cavity and bathes the cell

What is a closed circulatory system?

blood is contained within vessels and cells are bathed with interstitial fluid

What is an atrium?

a chamber of the heart that receives blood from the rest of the body

What is a ventricle?

a chamber of the heart that pumps blood out of the heart

What is an artery?

blood vessel that carries blood away from the heart

What are capillaries?

small blood vessels with thin walls; where exchange between blood and interstitial fluid occurs

What are veins?

blood vessels that carry blood towards the heart

What is single circulation?

blood travels from heart → gas exchange structures → body

Single circulation is ONLY found in this animal _________

fish

What is double circulation?

blood travels from heart → gas exchange structures → back to heart → body

What is a pulmonary circuit?

arteries and veins that circulate blood through gas exchange organs

What is a systemic circuit?

arteries and veins that circulate blood through all parts of the body

Describe blood flow in the pulmonary circuit.

pulmonary artery → lungs → pulmonary vein → left atrium → left ventricle → aorta

Describe blood flow in the systemic circuit.

aorta → arterioles → capillaries → vena cava → right atrium → right ventricle → pulmonary artery

Why do atria have thinner walls than ventricles?

they do not need to pump with as much force since they act as kind of a entryway

What is the sinoatrial node?

region of specialized cardiac muscle in the right atrium that sets rate and timing of contractions; pacemaker

What is the atrioventricular node?

found between atria; briefly delays electrical impulses generated from sinoatrial node before it gets to the ventricles

What are the layers of blood vessels?

inner endothelium → smooth muscle → connective tissue

Describe the anatomy of an artery.

thick layer of connective tissue and smooth muscle, smaller opening of endothelium

Describe the anatomy of a vein.

large opening with thinner smooth muscle/connective tissue layers; has flaps

Describe the anatomy of a capillary.

narrow diameter with a single layer of endothelial tissue

What is peripheral resistance?

resistance to flow that blood experiences as it is channeled into smaller blood vessels

How does blood flow without heart contractions?

skeletal muscle contractions, rhythmic contractions of smooth muscle within vessels, negative pressure generated by expansion of chest cavity

What are the mechanisms of exchange in capillary beds?

diffusion, endocytosis/exocytosis, bulk flow

What is bulk flow?

fluids and dissolved solutes under positive pressure are squeezed out between endothelial cells in capillaries

What is the lymphatic system?

a system of vessels and lymph nodes that return fluid, protein, and solutes to the blood

What is plasma made up of?

mostly water, ions, plasma proteins

What are the functions of ions in blood plasma?

osmotic balance, buffer pH, and regulate membrane permeability

What is the function of albumin?

osmotic balance and pH

What is the function of fibrinogen?

clotting

What is the function of immunoglobulins?

anitbodies

What is a respiratory medium?

the source of oxygen in the environment that an animal makes use of

What is a respiratory surface?

the part of an animal’s body where gases are exchanged between blood and the environment

What are tracheae?

air containing tubes that have openings to the external environment through spiracles; branches extensively within an animal’s body

What are gills?

out folds of the body surface that are suspended in water and carry out gas exchange between water and blood that permeate the gills

What are lungs?

respiratory surface that acts in one location of an animal’s body

How do aquatic animals extract enough O2 from water?

maintain high rates of water flow over the gills and extract the max possible through counter-current exchange mechanisms

What is ventilation?

any mechanism of increasing contact between oxygenated respiratory medium and respiratory surface

What are properties of respiratory surfaces?

high surface area, thin walls, moist cells

What are alveoli?

air sacs clustered at the tips of the bronchioles where gas exchange occurs

How do mammals ventilate their lungs?

negative pressure is used to draw air in and positive pressure is used to expel air

What regulates breathing rate?

medulla oblongata

During what activities can hemoglobin release more O2?

during exercise to provide O2 to muscle tissue

What pH will allow hemoglobin to release more O2?

lower pH to support increased cellular respiration

What is osmoregulation?

processes that regulate solute concentrations and balance the gain and loss of water from an animal’s body

What is excretion?

ridding the body of metabolic waste products

What is a osmoconformer?

an organism that maintains homeostasis to match their body fluid with the environment

What is an osmoregulator?

an organism that maintains homeostasis independently of the environment

What are transport epithelia?

layers of specialized epithelial cells that use ATP to move specific molecules or ions in a single direction

Which way will water flow in marine fish?

water flows out

What will marine fish excrete?

small amounts of highly concentrated urine

How do marine fish maintain osmolarity?

drink seawater and use transport epithelial to pump NaCl into surrounding sea water

Which way does water flow in freshwater fish?

water flows into the body

What do freshwater fish excrete?

large amounts of dilute urine

How do freshwater fish maintain osmolarity?

excrete large amounts of dilute urine and use transport epithelia to uptake ions from surrounding water

Which way does water flow in terrestrial organsims?

water flows out

How do desert animals adapt to conserve water?

loose little water through excretion, using the water in the tissues of their food and metabolic water to fuel the body

What is the function of the renal artery?

supplies the kidney with blood to be filtered

What is the function of the Bowman’s capsule?

absorbs the filtrate that was squeezed out of the capillaries of the glomerulus into the nephron

What is the function of the Loop of Henle?

establishes and maintains the strong osmolarity gradient from renal cortex into renal medulla

What is the function of the collecting duct?

carries filtrate through renal medulla and provides opportunity for extensive reabsorption of water

What is the function of the ureter?

conducts urine from the kidney to the bladder