BIOL 204 Lab For Week 12 Digestive Enzymes

Digestive Enzymes : are used in the lumen of the GI tract to break down complex molecules into absorbable subunits Enzymes are biological catalysts which increase the rate of a chemical reaction without themselves becoming part of the product:

In this experiment we will observe the activity of three different enzymes : Amylase:digests starch into disaccharides Trypsin:digests proteins into peptides Lipase:digests fats into glycerol and fatty acids

Variables tested …… 1.Incubation temperature: How will enzyme activity compare when incubated at O o C and 37 o C? 2.Denaturization of Enzymes How will enzyme activity be altered if the enzyme is denatured by boiling?

Activity 1Trypsin Activity Trypsin an enzyme, secreted by pancreatic acinar cells, that hydrolyzes proteins into small fragments (peptones, peptides and proteoses)”

In this experiment, trypsin will act on an artificial substrate to yield a yellow colored product: Trypsin BAPNA + H 2 ON-benzoyl-L-arginine + p-nitroaniline (yellow) 1.Reaction rate will be compared at these different incubation temperatures : 37 0 C and 0 o C What do you predict will happen? 2.The rate of the reaction will be determined using boiled trypsin. What do you predict will happen?

Activity 2Amylase Activity Amylase is a carbohydrate digesting enzyme, produced by salivary glands and pancreatic acinar cells, that hydrolyzes starch into maltose (disaccharides): Amylase Starch + H 2 Omaltose (disaccharides)

Indicators: Starch:IKI (Lugol’s solution) - turns “blue/black” in the presence of starch Benedict’s Solution:turns green/orange/ red/brown in the presence of reducing sugar

IKI Test For Starch in a Spot Plate Benedict’s Test for reducing sugar in heat test tubes

As in activity one, the reaction will be observed under different conditions: Boiled Enzyme (Amylase) Incubation Temperature: 0 o C and 37 o C

Activity 3 Lipase Activity Lipase is a hydrolytic enzyme, made primarily by pancreatic acinar cells, that hydrolyzes neutral fats into fatty acids and glycerol: Lipase Fat + H 2 OGlycerol + Fatty Acids

Fat Digestion: Indicator: Blue litmus terns pink (red) in the presence of acid (one the products is fatty acids)

Bile emulsifies fat….

In this activity, you will examine the effect of: incubation temperature (0 o C vs. 37 o C) and addition of bile salts on the reaction

Liver – Microscopic Anatomy

Microscopic View of the Pancreas: Islet Cells: endocrine; secrete insulin and glucagon Acinar Cells: exocrine; secrete digestive enzymes

BIOL 204 – Lab 12b The Reproductive System - Anatomy

Objective 1Structures of the Male Reproductive Tract A.The Scrotum LocationStructureFunction(s) located outside of theis a pouch of thin, darkhold the testes outside of the body cavity; belowskinbody cavity the root of the penis and the pubic the walls of the scrotum symphysiscontain the dartos muscle which, when contracted, gives the scrotum a wrinkled appearance contains numerous sebaceous glands the cremaster muscle raises and lowers the testes to ensure proper temperature for sperm production Scrotum

Tubules LocationStructureFunction Epididymus superior aspectcomma shapedadsorb excess testicular fluid of each testestube in a coiland secrete factors that make (6 m long)sperms more mature and motile has a head, a body and a tail Epididymus (Pink) H = head B = body T = tail

The Testes LocationStructureFunction(s) Each teste lies obliquely-oval; weight g-spermatogensis in the scrotum-4cmX 3cm X 2.5 cm-manufactures hormones supplied by the testicular artery and the testicular vein each teste is covered by a white, inelastic capsule called the tunica albuginea internally the teste is divided into 150 lobules each lobule has 1-3seminiferous tubules

LocationStructureFunction Vas (Ductus) travels upwardan epithelial tubecarries sperm into the body Deferens into the body about 45 cmcavity cavity as partlong; the expanded of the spermaticend is called the cordampulla it arches medially over the ureter anddescends along the posterior wall of the urinary bladder

LocationStructureFunction Ejaculatory Duct passes from thea short, 3cmcarries semen from the vas deferensepithelial tubevas deferens to the through theurethra prostate gland, to the urethra

LocationStructureFunction Urethra extends from thethere are threecarries both urine and urinary bladderportions:semen to the surface of the to the tip of thebody penis Prostatic portion: 2.5 cm long; begins at the internal urethral orifice and extends throughthe prostate gland Membranous portion: 1.5 cm long; travels through the urogenital diaphragm; the bulbourethral glands are at either side Penile portion: 15 cm long; travels through the penis in the corpus spongiosum

Glands StuctureLocationFunction(s) Seminal vesicles lobular, pairedposterior aspect produce about 1.5 to 3 ml of sticky glands about 5 cmof the bladderyellow fluid that contains fructose longand other nutrients for sperm and prostaglandins and vesciculase, a coagulating enzyme

StructureLocationFunction(s) Prostate Gland a single, donutencircles theproduces ml of shaped glandurethra at theslightly acidic fluid which base of thecontains enzymes which bladderactivate and nourish sperm

StructureLocationFunction(s) Bulbourethral small, pairedlocated in theproduce a few drops of Glands glandsurogenitalalkaline mucus which helps diaphragm,to neutralize vaginal acids inferior to the prostate gland

E. The Penis The penis is composed of tissue organized into three columns: (2) corpora cavernosa and (1) corpus spongiosum -the corpora cavernosa contains vascular sinuses -the corpus spongiosum contains the penile urethra; it expands at its end to form the glans penis; the glans is covered by a loose fold of tissue called the prepuce (foreskin)

Objective 2Histology Microscopic Anatomy of the Penis – X Section

Testes

Sperm

Objective 3Gross Anatomy - Female Note the uterus (with fundus, myometrium, cervix, perimetrium, endometrium, body); the ovaries, uterine tubes (with fimbriae), vagina, and the ligaments (suspensory ligament, broad ligament, ovarian ligament, round ligament)

Lateral View -

Female Breast Anatomy

Objective 4Ovary -Histology

Primary Follicles Graafian Follicles Corpus Luteum