BIO 181-Unit 4: Nutrition

Closed Circulatory System

Requires vessels to contain fluids that circulate around the organism

Open Circulatory System

Does not require vessels to contain fluids that circulate around the organism

Blood

Type of connective tissue composed of fluid matrix called plasma and formed elements

Aorta

Largest artery that begins transportation of blood to the body

Arteries

Transport oxygenated blood to organs and tissues

Capillary Beds

In tissues to receive blood

Veins

Transport deoxygenated blood to heart with the help of Venous pumps

Vena Cava

(inferior and superior) large veinule into the heart

Valves

Prevent backflow of blood when muscles are relaxed. Open and blood flows when muscles contract

Atroventricular Valves

maintain unidirectional blood flow between atria and ventricles. Tricuspid on right and Bicuspid/mitral on left

Semilunar Valves

Ensure one-way flow out of ventricles to arterial systems. Pulmonary on right and Aortic on left

Electrocardiogram

Records electrical activity in the heart. Contraction of atria, contraction of ventricles, and ventricles relaxing

Sinoatrial Node

On the right atrium wall that paces the heart's rhythm using autonomic nerves

Purkinje Fibers

Job is to stimulate the ventricles

Mechanical Digestion

Mastication, peristalsis, maceration, and segmentation

Chemical Digestion

Enzymatic activity: salivary amylase

Steps of Human Digestion

1. Swallowing
2. The Stomach
3. The Small Intestine
4. Fat Digestion and Absorption
5. Large Intestine/Colon

Epiglottis

Flap of cartilage at roof of tongue, depressed while swallowing to cover opening of trachea (windpipe)

Saliva

Helps prevent mouth from drying out, first line of defense against disease-causing microorganisms entering mouth, and helps form bolus

Bolus

Ball of food

Stomach

Has three muscle types: longitudal, oblique, and circular, churns pre-digested food, and absorbs ~10% of caffeine, aspirin, water if dehydrated

Phyloric sphincter

stomach to small intestine/duodenum

Duodenum

Emulsification/breakdown of fat globules into tiny droplets, which provides a larger surface area on which the enzyme pancreatic lipase can act to digest the fats into fatty acids and glycerol.

Jejunum & Ileum

~90% of absorption

Microvilli

In the Small Intestine space (lumen) that lines the wall in brush0like structure, VIP for digestion, catches the nutrients to absorb

Lacteal

Where the broken down fats are stored, pathway fat takes to go into cells

Cecum

"dead end pouch" in humans/bacteria

Appendix

Vestigial organ, or haven for bacteria when diarrhea flushes bacteria from the intestinesR

Rectum

~4.7" long->anal canal

Defecation

Removal of remaining waste material

Carbohydrate Breakdown

Starts in the mouth with salivary amylase

Protein Breakdown

Starts in stomach with pepsin

Lipids

Broken down fat globules into fatty acids

Xylem

Water and nutrients from roots to different parts of the plantP

Phloem

Organic compounds from photosynthesis sites to other parts of the plant

Sucrose

Gets transported from source cells into companion cellsTr

Translocation

Movement of materials from leaves to other parts of the plant

Cuticle

Waxy cover that prevents the plant from losing water

Transpiration

Causes water to return to leaves via xylem caused by evaporation of water at leaf-atmosphere interface

Stomata

Openings in the cuticle that take in and release water

Cohesion-Tension Theory

Evaporation from mesophyll cells produce a negative water potential gradient that causes water to move upwards from the roots through the xylem

Guttation

Exudation of drops of xylem sap on tips/edges of leaves of some vascular plants (grasses, some fungi)

Suspension/Filter feeders

Capture and ingestion of food particles that are suspended in water

Substrate feeders

Live in food source and eat as they burrow

Deposit feeders

Eat their way through dirt, picking up decayed organic material

Fluid feeders

Suck nutrient-rich fluids

Bulk feeders

Eat large pieces of food using adaptations such as claws, teeth, pinchers, and fangs, etc.