Transcript Location Structure Function

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 1
Trypsin 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 + H2O
1.
N-benzoyl-L-arginine + p-nitroaniline
(yellow)
Reaction rate will be compared at these different incubation
temperatures:
370 C and 0o 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 2
Amylase Activity
Amylase is a carbohydrate digesting enzyme, produced by
salivary glands and pancreatic acinar cells, that hydrolyzes
starch into maltose (disaccharides):
Amylase
Starch + H2O
maltose (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: 0oC and 37oC
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 +
H2O
Glycerol + 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 (0oC vs. 37oC)
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 1
A.
Structures of the Male Reproductive Tract
The Scrotum
Location
Structure
Function(s)
located outside of the
body cavity; below
the root of the penis
and the pubic
symphysis
is a pouch of thin, dark
skin
hold the testes outside of the
body cavity
the walls of the scrotum
contain 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
Location
Epididymus
superior aspect
of each testes
Structure
comma shaped
tube in a coil
(6 m long)
Function
adsorb excess testicular fluid
and secrete factors that make
sperms more mature and motile
has a head, a
body and a tail
Epididymus (Pink)
H = head
B = body
T = tail
The Testes
Location
Structure
Function(s)
Each teste lies obliquely
in the scrotum
-oval; weight 10-14 g
-4cmX 3cm X 2.5 cm
-spermatogensis
-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 1-3 seminiferous tubules
Vas (Ductus)
Deferens
Location
Structure
Function
travels upward
into the body
cavity as part
of the spermatic
cord
an epithelial tube carries sperm into the body
about 45 cm
cavity
long; the expanded
end is called the
ampulla
it arches medially over the ureter and descends along the
posterior wall of the urinary bladder
Ejaculatory Duct
Location
Structure
Function
passes from the
vas deferens
through the
prostate gland,
to the urethra
a short, 3cm
epithelial tube
carries semen from the
vas deferens to the
urethra
Location
Urethra
Structure
extends from the there are three
urinary bladder
portions:
to the tip of the
penis
Function
carries both urine and
semen to the surface of the
body
Prostatic portion: 2.5 cm long; begins at the internal urethral
orifice and extends through the 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
Stucture
Seminal vesicles lobular, paired
Location
posterior aspect
glands about 5 cm of the bladder
long
Function(s)
produce about 1.5 to 3 ml of sticky
yellow fluid that contains fructose
and other nutrients for sperm and
prostaglandins and vesciculase, a
coagulating enzyme
Structure
Prostate Gland a single, donut
shaped gland
Location
Function(s)
encircles the
urethra at the
base of the
bladder
produces 0.5-1 ml of
slightly acidic fluid which
contains enzymes which
activate and nourish sperm
Bulbourethral
Glands
Structure
Location
Function(s)
small, paired
glands
located in the
urogenital
diaphragm,
inferior to the
prostate gland
produce a few drops of
alkaline mucus which helps
to neutralize vaginal acids
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 2
Histology
Microscopic Anatomy of the Penis – X Section
Testes
Sperm
Objective 3
Gross 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 4
Ovary -Histology
Primary Follicles
Graafian Follicles
Corpus Luteum