SI worksheet 14 – Animal nutrition and gas exchange

How would you expect the digestive system of a hawk to compare with that of a seed-eating sparrow?

  1. The hawk would have a larger gastrovascular cavity
  2. The sparrows digestive system would be longer
  3. The hawk would have a gizzard, the sparrow would not
  4. The hawks digestive system would be longer
  5. The sparrow would have a gizzard, the hawk would not

Which of the following is an adaptation to a carnivorous diet?

  1. Sharp, pointed teeth
  2. Enlarged cecum
  3. Longer intestine
  4. Reingestion of feces
  5. Large populations of bacteria and protists in in special fermentation chambers in the alimentary canal

An open circulatory system _____.

  1. is less common in crabs and beetles than in mice and snakes
  2. unlike a closed circulatory system, does not rely on muscle contraction
  3. allows interstitial fluid to mix freely with vascular fluid
  4. restricts the backflow of blood by valves in the trachea
  5. has no valves

The function of the pulmonary circuit in a dog is to _____.

  1. carry oxygen and nutrients to tissues where they are needed
  2. retrieve waste products from the body tissues
  3. carry blood through the heart, lungs, and all of the body tissues
  4. carry carbon dioxide to the lungs and pick up oxygen from the lungs
  5. carry absorbed nutrients from the small intestine to the liver

In a fish, blood circulates through _____, whereas in a mammal, it circulates through _____.

  1. two circuits ... four circuits
  2. one circuit ... two circuits
  3. four circuits ... two circuits
  4. one circuit ... four circuits
  5. two circuits ... one circuit

What is unique about blood in pulmonary arteries compared with blood in other arteries?

  1. Blood in pulmonary arteries is always blue; it is red in all other arteries.
  2. It is moving away from the heart.
  3. It is moving toward the heart.
  4. It is loaded with carbon dioxide.
  5. There is no difference; it is the same as blood in other arteries.

In what parts of the body would the following be digested? (can be more than one part)

Carbohydrates – Mouth, stomach, small intestine

Protein – stomach, small intestine

Nucleic Acid – Small intestine

Fat – Small intestine

What does it mean when a cow is a “ruminant?”

Deer, sheep, and cattle are ruminants in which plant matter is cycled through multiple stomachs for optimal absorption of nutrients

What are the functions of the following hormones?

Ghrelin – secreted by the stomach wall, this hormone triggers feelings of hunger. In dieters Ghrelin levels increase, making it harder to diet

Insulin suppresses appetite by acting on the brain

Leptin is produced by fat tissues and suppresses appetite

What are the 3 main components of a circulatory system?

A set of interconnecting vessels, a circulatory fluid, and a muscular pump, or heart.

Heart pumps using metabolic energy to elevate the hydrostatic pressure of circulatory fluid, which flows through vessels back to the heart.

Compare and contrast an open circulatory system vs. a closed circulatory system

-Open circulatory system – found in arthropods and most molluscs where circulatory fluid bathes the organs directly.

  • Circulatory fluid called hemolymph or interstitial fluid bathes body cells. Contraction of one of more hearts pumps hemolymph through circulatory vessels into interconnected sinuses spaces surrounding organs.
  • Chemical exchange takes place in the sinuses between the hemolymph and body cells. Relaxation of the heart brings the hemolymph back in through pores with valves that close when the heart contracts.

-Closed circulatory system – a circulatory fluid called blood is confined into vessels and is distinct from the interstitial fluid.

  • One or more hearts pump blood into vessels that branch off into smaller ones that infiltrate organs. Chemical exchange is between blood and interstitial fluid as well as the fluid and the organs.
  • Annelids, cephalopods, and all vertebrates.

-Open circulatory systems require lower energy than closed because of lower hydrostatic pressure

-Closed systems have higher blood pressure and support larger body size. Good at regulating distribution of blood

Rearrange the following based on what order blood would travel through them if it is traveling through the systematic circuit (oxygen rich)

  1. Arterioles
  2. Venules
  3. Veins
  4. Capillaries
  5. Arteries
  6. Capillary beds

Correct:

  1. Arteries
  2. Arterioles
  3. Capillaries
  4. Capillary beds
  5. Venules
  6. Veins

What does the term Pulmocutaneous mean?

The Pulmocutaneous circuit in animals who exchange through skin is the same as the pulmonary circuit in animals with lungs.

Starting with the right ventricle describe the path of blood through the heart (including all chambers and circuits)

  1. Contraction of the right ventricle pumps blood to the lungs via the pulmonary arteries
  2. Blood flows through the capillary beds of the left and right lungs, loading up on O2 and dropping off CO2
  3. Oxygen rich blood returns through the pulmonary veins to the left atrium of the heart
  4. O2rich blood flows to the left ventricle which pumps the rich blood out through the aorta to the bodies tissues through the systematic circuit.
  5. The first branches leading from the aorta are the coronary arteries (which supply blood to the heart muscle itself)
  6. Next, branches from the aorta lead to capillary beds in the head and forelimbs.
  7. The aorta then descends to the abdomen supplying rich blood to arteries leading to capillary beds in the abdominal organs and legs.
  8. Within the capillary beds there is net diffusion of O2 and absorption of CO2. Capillaries rejoin, forming venules, which convey blood to the veins.
  9. The Superior vena cava collects O2 poor blood from the head and arms while the inferior vena cava does the same form the abdomen and legs.
  10. The two vena cava drain into the right atrium where the O2 poor blood flows into the right ventricle.

What is the difference between the semilunar and the atrioventricular valves?

Valves in the heart prevent backflow and keep blood moving in the correct direction

Atrioventricular (AV) valve – lies between each atrium and ventricle and anchored by strong fibers to prevent them from turning out. (first “dub”)

Semilunar valve – Located at the two exits, Where the aorta leaves the left ventricle and the pulmonary artery leaves the right ventricle. (second “dub”)