Lab - Pigeon Viscera

Question 1

Follow the path that food would take through the digestive system of the pigeon

Answer 1

mouth - pharynx - esophagus - crop - proventriculus - gizzard - duodenum - small intestine - large intestine - coprodium - proctodium

Question 2

The thoracic and abdominal cavities are separated by a ________. This is homologous to the _______ of the turtle.

Answer 2

Oblique septum - homologous to the transverse septum of the turtle

Question 3

Follow the path that eggs and sperm would go down

Answer 3

Egg: Ovary - ostium - oviduct - vagina - urodeum - proctodeum

Sperm: testes - epididymis - vas deferens - urodeum - proctodeum

Question 4

What is the role of the gizzard? The crop?

Answer 4

The gizzard is a large, hardened muscular portion of the stomach and is lined with a horny lining for grinding food (sometimes this lining is little rocks). The crop is a thin-walled sac at the bottom of the esophagus that retains food temporarily, can be used to regurgitate food to the young, and the walls of the crop also secrete a milky substance that can be used to feed the young

Question 5

The thoracic cavity contains 3 cavities: _____, _____, and _____

Answer 5

The pericardial cavity (contains heart), and two pleural cavities containing the lungs

Question 6

The liver is supported by a ____ ligament, which extends to the body wall

Answer 6

Falciform ligament

Question 7

What mesenteries attach to the gizzard?

Answer 7

1. Ventral ligament attaches gizzard to ventral body wall (continuous with falciform) 2. Gastrohepatic ligament extends between gizzard and liver 3. Mesogastric mesentery connects gizzard with dorsal body wall

Question 8

What is the significance of the colic cecae?

Answer 8

They house cellulose-digesting bacteria, and are much larger in birds that eat twigs and leaves

Question 9

What kidney type is seen in birds?

Answer 9

Metanephric

Question 10

The pancreas lies within the ____ ligament

Answer 10

Medoduodenal ligament

Question 11

The duodenum attaches to the liver via the ____ ligament

Answer 11

hepatoduodenal

Question 12

The rest of the small intestine is supported by the _____

Answer 12

mesentery proper

Question 13

Name the structures in this photo

Answer 13

A - small intestine

B - Pancreas

C - Gizzard

Question 14

Name all the structures in these diagrams

Answer 14

A - Operculum

B - Palatine fold

C - Nasal cleft

D - Eustachian tube opening

E - Conical papillae

F - Esophagus

G - Beak

H - tongue

I - Horny papillae

J - Glottis

K - Conical papillae

L - Esophagus

Question 15

What areas of the cloaca are indicated by this photo? What empties into each? What area do they both empty into?

What is unique about this area in young birds?

Answer 15

A - Coprodeum (large intestine/colon)

B - Urodeum (Vas deferens and ureter)

They empty into a proctodeum

Young birds have a “bursa of Fabricius” in their proctodeum, which helps the immune system

Question 16

How does air flow into the lungs in the bird? Describe sound production in the bird

Answer 16

Air flows down the trachea to the right and left bronchi and through the lungs/air sac system. On the surface of the lung is a muscle known as the diaphragmaticus muscle.

Sound is produced by the syrinx, by vibrations of the internal tympaniform membrance and the external tympaniform membrane. Two sternotacheal muscles extend from the sternum to the syrinx. The intrinsic syringeal muscles run along the trachea and insert onto the syrinx. More muscles = better singing

Question 18

The ureter runs parallel to the _______

Answer 18

ducts of the reproductive system (vas deferns or oviduct)

Question 19

How do birds rid themselves of nitrogenous wastes without the presence of a bladder

Answer 19

Birds temporarily store wastes in the urodeum.

Question 20

What is the structure indicated in this photo?

Answer 20

The kidney

Question 21

How do birds eliminate waste?

Answer 21

Birds produce nitrogenous wastes in the form of uric acid, which allows for much higher water retention than other forms of waste.

Question 22

Why do female birds only have gonads on the left side of their body?

Answer 22

This is presumably as an adaptation for weight reduction for flight

Question 23

Fertilization occurs in the ____ of the oviduct. What happens in each section of the oviduct?

Answer 23

Magnum.

Magnum - Fertilization occurs and the albumen is added.

Isthmus and uterus - supply egg membranes and shell

Question 24

How would the pectoral muscles and sternum differ in flapper, glider, and non-flying birds?

Answer 24

In strong fliers, the pectoralis and supracoracoideus may take up more than 30% of body weight!

In gliders and soarers, the keel of the sternum is reduced and pectoral muscles are less bulky.

In non-flying birds we would expect to see a smaller keel and smaller pectoral muscles, simply because they are not needed. The exception to this is the penguin, which needs strong pectoral muscles to swim.

Question 25

What is the significance of the patagial tendon?

Answer 25

When the patagial tendon is pulled taut it automatically extends the wrist, reducing muscle bulk and effort required to extend the wing

Question 27

Very briefly describe the flow of air through the pigeon lung/air sacs

Answer 27

Inhalation - Air flows down trachea , past respiratory surfaces and into air sacs (the air sacs are connected by a circle in the lung. Air enters the posterior air sacs without passing a respiratory surface

Exhalation - Air is pushed out of each air sac and all goes back up the trachea without once again passing the parabronchi. Air from the posterior air sacs is passed by the parabronchi for the first time on their way out