chapter 32 pp Flashcards Preview

Biology 1201: Organisms and Diversity > chapter 32 pp > Flashcards

Flashcards in chapter 32 pp Deck (68)
Loading flashcards...
1

Small aquatic animals with no circulatory system

Each cell is exposed to water and can independently exchange gases and eliminate wastes.

2

Pseudocoelomates

“false cavity”
Use the coelomic fluid of their body cavity as a means of transporting substances

3

Coelomate echinoderms

: double lined gut cavity
Also rely on movement of coelomic fluid within a body cavity as a circulatory system
May still rely on body fluids for the purpose of locomotion

4

Two types of circulatory fluids

Blood – contained within blood vessels
Hemolymph – mixture of blood and tissue fluid that fills the body cavity and surrounds internal organs

5

Open Circulatory System

They were first to evolve.
The heart pumps hemolymph via vessels.
Vessels empty into tissue spaces.
Hemolymph drains back into heart

6

Closed Circulatory System

Most cells in the body aren’t far from a capillary.
Heart pumps blood to capillaries.
Gases and materials diffuse to and from nearby cells.
Vessels return blood to the heart without contact between blood and tissues.

7

cardiovascular system.

All vertebrates have a closed circulatory system

8

Vertebrate heart

Atria of the heart receives blood from general circulation
Ventricles of the heart pump blood out through blood vessels

9

Vertebrate vessels

arteries, arterioles, capillaries, venules, veins

10

Arteries

Carry blood away from heart

11

Arterioles

Small arteries which lead to capillaries
Diameters are regulated by nervous and endocrine systems (ex. Temp. control).

12

Capillaries

Exchange materials with tissue fluid (interstitial)

13

Venules

Join to form a vein

14

Veins

Return blood to heart
Both venules and veins collect blood from capillary beds

15

fish

Blood flows in single loop
Single atrium and single ventricle

16

Amphibians

Blood flows in double loop
Systemic circuit and pulmonary circuit
Two atria with a single ventricle

17

Most reptiles

A septum partially divides the ventricle
Mixing of oxygen-rich and oxygen-poor blood is kept to a minimum.
In crocodilians, septum completely separates the ventricle.

18

Birds and mammals

Blood flows in a double loop (two circuits)

19

Birds and mammals types of circuits in circulatory system

The heart is also divided by septum into separate sides.
Right ventricle pumps blood to lungs; left ventricle pumps blood to rest of body.
Blood pressure is adequate for both pulmonary and systemic circuits.

20

The Human Heart

Fist-sized
Located between lungs directly behind sternum (breastbone)
Muscular organ (cardiac fibers)
Lies within a membranous sac (the pericardium)

21

vessels

c

22

The septum

separates the heart into left and right sides.
Each side has two chambers.

23

atria in the human heart

Upper two chambers are the atria
Thin-walled
Receive blood from circulation

24

ventricles in the human heart

Lower two chambers are the ventricles
Thick-walled
Pump blood away from heart

25

Valves
Types of valves

open and close to control blood flow through the heart.
1. Atrioventricular valves
2. Semilunar valves

26

Atrioventricular valves

Tricuspid valve between right atrium and ventricle
Bicuspid valve between left atrium and ventricle

27

Semilunar valves

Pulmonary semilunar valve between right ventricle and pulmonary trunk
Aortic semilunar valve between left ventricle and aorta

28

Systole

Contraction of heart chambers

29

Diastole

Relaxation of heart chambers

30

Cardiac cycle

Two-part pumping action that takes about a second