Chapter 32 Flashcards

1
Q

Homeostasis

A

A condition in which the internal environment of the body remains relatively constant despite changes in the external environment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why is homeostasis so important?

A

Failure to maintain homeostasis results in imbalances, later causing sickness, disease, and death.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Lowest heart rate occurs at what time of the day?

A

Around 3am because we are asleep, so we have slower heartbeat.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Morning hypertension occurs around what time?

A

Around 7am because of the rapid rise in blood pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What time of the day is the highest risk of cardiac arrest?

A

Around 10am because of dehydration and the constriction of blood vessels.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What time of the day does a person have the fastest reaction time?

A

Around 3pm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What time of the day does a person have the greatest muscle strength?

A

Around 7pm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What time of the day does the secretion of melatonin begin?

A

Around 9pm. Pineal melatonin secretion occurs during the nighttime. Melatonin secretion involves the regulation of the human circadian core body temperature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Levels of biological organization:

A

Cell- Tissue- Organ- Organ System- Organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What function does the cell membrane perform to maintain homeostasis?

A

Cell membranes help organisms maintain homeostasis by transporting or moving material in and out of the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What methods of transport are responsible for exchange across the cell membrane?

A

Passive, active, and bulk transports

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does the size of a cell effect exchanges made by the cell to it’s environment?

A

The size of a cell directly affects how it exchanges with its environment. Exchange is effective over very short distances. A large cell is limited by the distance materials must travel from the center of the cell to its surface, which ultimately causes the cell to not satisfy metabolic demands.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does exchange work in single cell organisms?

A

Exchange occurs by simple diffusion. Exchange is simple because the organism is small in size and has direct contact with external environment (lives in water).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does exchange work in multicellular organisms?

A

Exchange occurs by simple diffusion. Each cell has its own plasma membrane, so each layer of cells is in direct contact with the external environment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does exchange work in complex multicellular organisms?

A

Cells are embedded inside the organism and therefore isolated from direct contact with the external environment. Exchange surfaces include digestive, respiratory, and circulatory systems, meaning large organisms need more specialized transport systems or diffusion would be too slow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How can cells with no direct contact with the external environment make exchanges?

A

Those needs are met by the internal environment, namely the extracellular fluid which allows for the movement of material into and out of the cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Passive Transport

A

Does not use the cell’s energy in brining materials in and out of the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Active Transport

A

Does use the cell’s energy in bringing materials in and out of the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Bulk Transport

A

Involves the cell making membrane bound vesicles to bring materials in and out the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What two components make up the extracellular fluid?

A

Plasma and interstitial fluid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Plasma

A

Fluid portion of blood.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Interstitial fluid

A

Fluid that surrounds the cells, sometimes referred to as tissue fluid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the role of extracellular fluid?

A

Connects all cells to the external environment so no matter where a cell is located it can make the exchanges essential to life.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What level of biological organization enables the exchanges between the internal and external environments?

A

Organ systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the primary function of the cell membrane?

A

It allows certain materials to enter and exit the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Interstitial fluid and plasma are both considered _______ fluid and make up the ________ of the body.

A

intracellular; internal environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Interstitial fluid is…

A

the route for the exchange of materials between blood and body cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Cell is…

A

the smallest unit of life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Tissue is…

A

an organized group of cells, working together as a functional unit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the 4 types of tissues?

A

Epithelial, connective, muscle, nervous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Where is epithelial tissue located?

A

Cover the surface of the body and lines the cavities within the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the two surfaces of connective tissue?

A

Apical surface is the free side that faces away from other tissues.
Basolateral surface is the secured side which is tightly bound to neighboring cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Epithelial tissues are classified according to…

A

Shape (squamous, cubodial, columnar) and Layers (simple or stratified)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Function of connective tissue is…

A

mainly binds and supports other tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Loose connective tissue:

A

binds epithelial cells to underlying tissues and holds organs in place

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Dense connective tissue:

A

has more collagen fibers. Includes tendon (attaches muscle to bone) and ligament (attaches bone to bone).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Blood:

A

is composed of blood cells and cell fragments in the blood plasma. (classified as a tissue, does not connect but transports)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Cartilage:

A

is a strong and flexible support material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Adipose tissue:

A

stores fat for insulation and fuel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Hyaline cartilage:

A

flexible and resilient and not easily compressed, within joints and nose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Elastic cartilage:

A

is flexible and bendable yet rigid, ear and larynx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Fibrocartilage:

A

is sturdy, tough and inflexible, knee

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is the function of muscle tissue?

A

It is responsible for all types of body movement.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What do muscles consist of?

A

They consist of filaments of the proteins actin and myosin, which enable muscles to contract.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What are the three types of muscle tissue?

A

Skeletal, Cardiac, and Smooth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Smooth Muscle

A
  • No striations, spindle shaped cells
  • Single nucleus in each cell
  • Found in the walls of blood vessels and visceral organs
  • Involuntary contractions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Skeletal Muscle

A
  • Striated appearance
  • Cells are multinucleated
  • Attached to bone by tendons
  • Voluntary contractions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Cardiac Muscle

A
  • Striated and branched appearance
  • Single nucleus
  • Contain gap junctions
  • Involuntary contractions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What is the function of Nervous Tissue?

A

Sense stimuli and transmit information. It coordinates, regulates, and integrates many body functions.

50
Q

What does nervous tissue consist of?

A

Neurons and glial cells

51
Q

Neuron function

A

transmit nerve impulses

52
Q

Glial cells function

A

support cells and supply nutrients

53
Q

The four principal types of tissues are:

A

Epithelial, connective, muscle, nervous

54
Q

How does size relate to the speed of diffusion?

A

Diffusion will be the most rapid when the size of the cell is the smallest/thinnest

55
Q

Blood is classified aa a(n) ______ tissue.

A

Connective

56
Q

Nerve cells are essential to an animal because they directly provide…

A

communication between cells

57
Q

What is the function of organ systems?

A

Work together to maintain homeostasis.

58
Q

Communication usually occurs via the control and coordination of which two systems?

A

Endocrine system and Nervous system

59
Q

Endocrine system

A
  • Does not have ducts to carry away their secretions

- Hormones pass directly into bloodstream for distribution around the body

60
Q

Exocrine system

A
  • Does consist of ducts to carry away their secretions out of the body
61
Q

Coordination and Control of the Endocrine system

A

Endocrine cells transmit chemical signals called hormones. These hormones travel through the body via blood.

62
Q

How does the function of hormones work?

A

Hormones can reach all parts of the body but only cells with a matching receptor will respond.

63
Q

Coordination and Control of the Nervous system

A

Nervous system transmits signals between specific locations via nerve impulses which travel along neurons

64
Q

Partners in Homeostasis: Endocrine system

A
  • Hormones
  • Slow acting, long lasting
  • Adapted for growth and development, reproduction, digestion
65
Q

Partners in Homeostasis: Nervous system

A
  • Nerve impulses
  • Fast acting, short lived
  • Adapted for fast movement and behavior
66
Q

Control system function

A

Regulate large external fluctuations in external environment into small fluctuations in the internal environment

67
Q

What is the primary mechanism of homeostasis?

A

Negative feedback

68
Q

Negative feedback

A
  • produces a response that restores the normal balance

- reverses the direction of change

69
Q

Positive feedback

A
  • amplify a change
  • rare in biological systems
  • does not usually contribute to homeostasis in animals
70
Q

What are the three functional components to homeostatic regulation?

A

Sensor, integrating center, and effector

71
Q

Sensor

A
  • membrane protein

- detects a stimulus or a changing condition outside and within the body

72
Q

Integrating Center

A
  • control center
  • compares condition to a set point
  • if conditions are too far from the set point, biochemical reactions are initiated to change condition back to set point
73
Q

Effector

A
  • cell or organ

- responds to the command and produces a response to either oppose or enhance the stimulus

74
Q

In a negative feedback mechanism, the response of the effector…

A

Reverses the activity of the original stimulus

75
Q

Why is thermoregulation important?

A

Thermoregulation helps animals maintain their internal temperature within a set of range that is optimal for survival of body cells.

76
Q

Thermoregulation in humans

A
  • core body temperature is maintained
77
Q

How does the human body measure temperature?

A

Hypothalamus. The hypothalamus contains a group of nerve cells that function as a thermostat.

78
Q

Where does the hypothalamus receive signals from that detects temperature?

A
  • Peripheral thermo-receptors in the skin

- Central thermoreceptors in the hypothalamus and CNS

79
Q

What happens if your body detects the body as too warm?

A

Vessels dilate (vasodilation) in the skin and sweating begins

80
Q

What happens if your body detects the body as too cold?

A

Vessels constrict (vasoconstriction) and shivering begins

81
Q

Endothermic animals

A
  • body chemistry regulates our temperature and keeps it constant
  • uses metabolism to generate heat and regulate their body temperature
  • can generate heat and have mechanisms for cooling
    Examples: mammals and birds
82
Q

Ectothermic animals

A
  • gain their heat from their environment, not from metabolism
  • adjust their temperature by behavioral means like basking in the sun and seeking shade
    Examples: invertebrates, fish, amphibians, reptiles
83
Q

Disadvantages of being an Endotherm

A
  • energetically expensive

- need more food than ectotherms

84
Q

The homeostatic thermostat which facilitates the process of thermoregulation is present in the…

A

hypothalamus

85
Q

If body temperature decreases, what wouldn’t occur?

A

sweating

86
Q

An ectotherm is:

A

An animal whose body temperature changes depending on the temperature of the environment

87
Q

An endotherm is:

A

An animal who can maintain a stable body temperature internally

88
Q

Which of the following is NOT an example of a homeostatic mechanism?

A

Using blankets to cover up when the body feels cold

89
Q

Thermoregulation depends on what?

A

An animal’s ability to exchange heat with its environment.

90
Q

What are the five methods of thermoregulation?

A

(1) Insulation, (2) circulatory adaptations, (3) cooling by evaporative heat loss, (4) behavioral responses, (5) adjusting metabolic heat production

91
Q

Insulation

A
  • reduces heat flow between animal and its environment

Sources: hair, feathers, layers of fat formed by adipose tissue

92
Q

Circulatory Adaptations

A
  • change in vessel diameter

- countercurrent heat exchange

93
Q

Countercurrent heat exchange

A

Warmer arterial blood flowing from the body’s core transfer heat to cooler venous blood returning from the extremities

94
Q

Cooling by Evaporative Heat Loss

A
  • sweat production increases when the body begins to overheat
  • sweat absorbs heat when it evaporates
95
Q

Behavioral Responses

A
  • Change of location (sun or shade)
  • Change of position (movement to increase metabolic rate)
  • Huddling to conserve heat
96
Q

Adjusting Metabolic Heat Production

A
  • shivering (increased contraction of muscles)
  • hormones (cause mitochondria to produce heat instead of ATP)
  • Brown fat (turn food into body heat)
  • Only human newborns and hibernating mammals have high levels of brown fat
97
Q

How do animals energy budget?

A

They reduce their basal metabolic rate (BMR) which helps save energy.

98
Q

What does energy budgeting produce?

A

Produces a state of dormancy called Torpor.

99
Q

Torpor can be:

A

Daily (bats at night, hummingbirds at night) and Long-Term (hibernation and estivation)

100
Q

Function of the Immune System

A

protects the body by fighting infection and cancer

101
Q

Lymphatic Organs

A

Primary Lymphatic Organs: red bone marrow, thymus

Secondary Lymphatic Organs: lymph nodes, spleen, tonsils

102
Q

Primary Lymphatic Organ: Red Bone Marrow

A
  • site of blood cell production

- B cells are produces and mature here

103
Q

Primary Lymphatic Organ: Thymus

A
  • Bilobed; in the thoracic cavity superior to the heart
  • Shrinks as we age
  • Functions: produces thymosin (induces the maturation of T cells) and T cells mature and reside here
104
Q

Secondary Lymphatic Organ: Spleen

A
  • filters blood
  • upper left region of the abdominal cavity
  • connective tissue divides it into white pulp and red pulp
105
Q

Macrophages

A
  • located in red pulp

- removes pathogens, debris, and worn out red blood cells from the blood

106
Q

Lymph nodes

A
  • found along the lymphatic vessels
  • filter lymph
  • filled with macrophages that engulf pathogens and debris
  • house lymphocytes, which fight infections and cancer cells
107
Q

Cytokines

A

produced by macrophages, B lymphocytes, T lymphocytes and mast cells

108
Q

Antigens

A

proteins that are foreign to the organism

109
Q

Antibodies

A

proteins produced by your body that bind to specific antigens

110
Q

Natural killer cells

A
  • kills virus infected and cancerous cells

- kills cells that lack surface proteins

111
Q

T cells

A
  • regulate immune responses; produce cytotoxic T cells and helper T cells
  • T cells are unable to recognize an antigen without antigen-presenting cells, such as a macrophage
112
Q

When does the activation of a T-cell occur?

A

When its T-cell receptor (TCR) can combine with an antigen presented by a macrophage.

113
Q

How do Cytotoxic T cells kill infected cells?

A
  1. Cytotoxic t cells bind to virus infected cell
  2. Perforin is released and punches holes in the plasma membrane, forming a pore
  3. Granzymes are delivered into the pore
  4. Apoptosis occurs in the virus infected cell
114
Q

What is the function of Helper T cells?

A

secrete cytokines that enhance the response of all types of immune cells

115
Q

Passive Immunity

A
  • Antibodies pass from mother to fetus via placenta or to infant via the mother’s milk
  • Preformed antibodies in immune serum are introduced by injection
116
Q

Active Immunity

A
  • Antigens enter the body naturally; body induces antibodies and specialized lymphocytes
  • Antigens are introduced in vaccines; body produces antibodies and specialized lymphocytes
117
Q

Tissue Rejection

A
  • Rejection of transplanted tissue results because the recipient’s immune system recognizes that the transplanted tissue is not “self”
  • Cytotoxic T cells attack the transplanted tissue
118
Q

Acquired Immune Deficiency

A

results from infection with the human immunodeficiency virus (HIV)

119
Q

Autoimmune Disease

A
  • Cytotoxic T cells attack the body’s own cells as if they were foreign
120
Q

Rheumatoid Arthritis

A
  • Inflammation in skeletal joints

- T-cells deteriorate the joints

121
Q

Multiple Sclerosis (MS)

A
  • T cells attack the myelin sheath covering nerve fibers

- Causes central nervous system dysfunction, double vision, and muscular weakness