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Flashcards in biology chapter 5 Deck (60):
1

protozoans

movement of gases and nutrients is accomplished by simple diffusion within the cell

2

cnidarians

have body walls that are two cells thick. All cells are in direct contact with either the internal or external environments so there is no need for a specialized circulatory system

3

arthropods

have open circulatory sytems in which their blood-like fluid (interstitial fluid) is in direct contact with the body tissues. The fluid is circulated primarily by body movements. Fluid flows through a dorsal vessel and into spaces called sinuses where exchange occurs

4

annelids

use a closed circulatory system to deliver materials to cells that are not in direct contact with the external environment

5

aorta

which branches into a series of arteries

6

capillaries

converge into venules, and eventually into veins, leading deoxygenated blood back toward the heart

7

right side of heart

pumps deoxygenated blood into pulmonary circulation (toward the lungs)

8

left side of heart

pumps oxygenated blood into systemic circulation (throughout the body)

9

atria

two upper chambers. Thin walled

10

ventricles

two lower chambers. Are extremely muscular

11

left ventricle

more muscular than the right ventricle because it is responsible for generating the force that propels systemic circulation and because it pumps against a higher resistance

12

atrioventricular valves

located between the atria and ventricles on both sides of the heart, prevent backflow of blood into the atria

13

tricuspid valve

the valve on the right side of the heart that has three cusps

14

mitral valve

valve on the left side of the heart that has two cusps

15

semilunar valves

have three cusps and are located between the left ventricle and the aorta (the aortic valve) and between the right ventricle and the pulmonary artery (the pulmonic valve)

16

heartbeat

made up by the systole and diastole

17

systole

is the period during which the ventricles contract

18

diastole

is the period of cardiac muscle relaxation during which blood drains into all four chambers

19

cardiac output

is defined as the total volume of blood the left ventricle pumps out per minute. = heart rate x stroke volume

20

heart rate

number of heartbeats per minute

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stroke volume

volume of blood pumped out of the left ventricle per contraction

22

sinoatrial (SA) node

a small mass of specialized tissue located in the wall of the right atrium. It spreads impulses through both atria, stimulating them to contract simultaneously

23

autonomic nervous system

modifies the rate of heart contraction

24

arteries

are thick walled, muscular, elastic vessels that transport oxygenated blood away from the heart-- except for the pulmonary arteries, which transport deoxygenated blood from the heart to the lungs

25

veins

are relatively thinly walled, inelastic vessels that conduct deoxygenated blood towards the heart-- except for the pulmonary veins, which carry oxygenated blood from the lungs to the heart

26

capillaries

have very thin walls composed of a single layer of endothelial cells across which respiratory gases, nutrients, enzymes, hormones, and wastes can easily defuse. They have the smallest diameter of all three types of vessels; red blood cells must often travel through them single file

27

lymph nodes

are swellings along lymph vessels containing phagocytic cells (leukocytes) that filter the lymph, removing and destroying foreign particles and pathogens

28

plasma

is the liquid portion of the blood

29

erythrocytes (red blood cells)

are the oxygen carrying components of blood

30

oxyhemoglobin

when hemoglobin binds oxygen

31

leukocytes (white blood cells)

are larger than erythrocytes and serve protective functions

32

platelets

are cell fragments that lack nuclei and are involved in clot formation as well as wound healing

33

serum

the fluid left after blood clotting

34

humoral immunity

involves the production of antibodies

35

cell-mediated immunity

which involves cells that combat fungal and viral infection

36

lymphocytes

are responsible for both of these immune mechanisms

37

immunoglobulins

are complex proteins that recognize and bind to specific antigens and trigger the immune system to remove them

38

active immunity

refers to the production of antibodies during an immune response

39

passive immunity

involves the transfer of antibodies produced by another individual or organims

40

gamma globulin

the fraction of the blood containing a wide variety of antibodies, can be used to confer temporary protection against hepatitis and other diseases by passive immunity

41

skin

is a physical barrier against bacterial invasion

42

macrophages

engulf and destroy foreign particles

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interferons

diffuse to other cells, where they help prevent the spread of the virus

44

antigens

are macromolecules that are foreign to the host organism and trigger an immune response

45

type AB blood

is the "universal recipient" as it has neither anti-A nor anti-B antibodies

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type O blood

is considered to be the "universal donor"; it will not elicit a response from the recipient's immune system since it does not possess any surface antigens

47

stem

is the primary organ of transport in the plant

48

vascular bundles

run up and down the stem

49

xylem

are thick-walled, often hollow cells located on the inside of the vascular bundle (towards the center of the stem). They carry water and minerals up the plant and their thick walls give the plant its rigid support

50

sapwood

what the outer layer of xylem is called

51

transpiration pull

as water evaporates from the leaves of plants, a vacuum is created which pulls water up the stem

52

capillary action

any liquid in a thin tube will rise due to the surface tension of the liquid and interactions between the liquid and the tube

53

root pressure

water entering the root hairs exerts a pressure which pushes water up the stem

54

phloem

are thin walled cells on the outside of the vascular bundle. They usually transport nutrients (especially carbohydrates produced in the leaves) down the stem

55

cambium

(two layers thick) are the actively dividing, undifferentiated cells which give rise to xylem and phloem.

56

fibrovascular bundle

composed of the phloem, cambium and xylem layers

57

gross structure of a woody stem

proceeding from the outside inwards, the following layers occur: epidermis (outer bark), cortex, phloem, cambium, xylem, and pith (tissue involved in storage of nutrients and plant support)

58

root

functions to absorb materials through the root hairs and anchor the plant

59

root hairs

are specialized cells of the root epidermis with thin-walled projections. They increase the surface area for absorption of water and minerals from the soil

60

meristem

refers to the actively dividing, undifferentiated cells of a plant