Chapter 28 Biology lab

Digestive system

breaks down complex food into smaller molecules, absorbs nutrients

Intracellular digestion

digestion that occurs inside cell

Extracellular digestion

digestion that occurs outside cell (protozoa, sponges)

Active transport

moves food through simple tract (flatworms have secular/single digestive tract in which food enters mouth, then chamber for digestion and absorption, and then expelled through the same hole it entered)

Tubular digestive system

food travels from mouth to organs, nutrients are absorbed, undigested food expelled as waste through anus 

(arthropods and annelids; tube includes a storage area, grinding area, digestive area, absorptive area)

(in vertebrates, tube is longer to increase the surface area of absorption)

Excretory system

expels nitrogenous waste from body (nitrogen-containing compounds of waste and ammonia)

(in aquatic animals, some excrete ammonia directly into the water via gills as a byproduct of protein metabolism)

(in invertebrates, body’s salt and water maintained by reducing dilute urine while eliminating water via osmosis)

Kidneys

filter water, absorb nutrients, excrete urine

Urogenital system

excretory + reproductive system 

Oogenesis

egg production, eggs released when female reaches sexual maturity

Spermatogenesis

sperm production, occurs in testes, billions of sperm are produced at sexual maturity

Renal cortex

outer kidney layer, lighter in color

Renal medulla

inner kidney layer, maintains fluid and electrolyte balance, produces urine

Calyces/renal pelvis

collect urine into the bladder

Nephron

functional and structural unit of kidney

Glomerulus

cluster of filtration capillaries in Bowman’s capsule, step 1 of filtration

Proximal tubule

reabsorbs water, nutrients, and electrolytes

Distal tubule

reabsorbs water and solutes

Collecting duct

final water reabsorption, pH balance

Scrotum

supports testes

Seminiferous tubules

sperm production within testes

Epididymis

sperm storage, tightly coiled tube

Vas deferens

sperm duct, enters via the urethra

Accessory glands

secrete fluid to nourish sperm (seminal vesicles, prostate, bulbourethral)

spermatocyte

produces 4 sperm, primary spermatocyte becomes secondary, then they divide again

Ovaries

small, bean-shaped organs, egg production

Fallopian tubes/oviduct

site of fertilization; where 1 egg is formed, around 400 in a lifetime

Uterus

houses embryo, opens to vagina

follicular stimulating hormone (FSH)

stimulates follicle development (fluid filled capsule in which eggs mature, and ruptured follicle allows the release of an egg) 

Ovulation

follicle ruptures, egg released

Menstrual cycle

hormones from pituitary gland stimulate follicles to secrete estrogen and progesterone, regulate egg release

Circulatory system

complex network of organs that transport blood

Heart

pumps blood throughout the body

Hemoglobin

iron and protein containing pigment that carries oxygen with erythrocytes

erythrocytes (RBCs)

red blood cells, transport oxygen from lungs to tissues, carry carbon dioxide back to lungs

leukocytes (WBCs)

white blood cells that function in immune defense

Platelets

function in blood clotting, form a platelet plug

Open circulation

blood is not enclosed within blood vessels, instead, hemolymph is fluid pumped into body cavity called hemocoel that bathes organs and then returns to the heart via the ostia

Closed circulation

in vertebrates, blood is confined to vessels such as arteries, veins, and capillaries, in which deoxygenated blood is pumped away from the heart and oxygenated blood is pumped towards the heart

Aorta

largest artery in the body, carries oxygenated blood

Capillaries

site of gas exchange, O2 and nutrients exchanged via diffusion

Lymphatic system

pump-like system that prevents fluid buildup in tissues

Edema

swelling from fluid buildup in tissues

Lymph nodes

site where lymph is filtered (bacteria is removed and lymph is returned to system)

Pericardial sac

protective covering of heawrt

4 chambers of the heart

2 atria, 2 ventricles

right side of heart

pumps blood to lungs from the vena cava

superior vena cava

bring deoxygenated blood from the upper body

inferior vena cava

bring oxygenated blood from the lower body

Ductus arteriosus

fetal blood shunt

Arteries

thicker, muscular, oxygenated blood with higher blood pressure

Veins

thinner, deoxygenated blood, lower pressure, valves to avoid backup and assure that blood flows in the correct direction

Varicose veins

backflow of blood in legs, occurs when the vein valves do not function

Plasma

fluid and water portion of blood, contain protein, salts, nutrients, wastes

percentage of WBCs and RBCs

~5% of blood cells are white blood cells

~95% of blood cells are red blood cells