Chapter 40-2 Flashcards
1
Q
connective tissue
A
o Consists of sparse population of cells scattered through an extracellular matrix
o Holds many tissues and organs together and in place
2
Q
collagenous fibers
A
provide strength and flexibility
3
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reticular fibers
A
join connective tissue to adjacent tissues
4
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elastic fibers
A
make tissues elastic
5
Q
matrix
A
consists of web of fibers embedded in liquid, gel-like, or solid foundation
6
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fibroblasts
A
secrete fiber proteins
Found in matrix
7
Q
macrophages
A
engulf foreign particles and cell debris via phagocytosis
8
Q
Loose connective tissue
A
binds epithelia to underlying tissues and holds organs in place
• Name derived from loose weave of fibers
9
Q
fibrous connective tissue
A
dense with collagenous fibers
• Found in tendons and ligaments
10
Q
tendons
A
attach muscle to bone
11
Q
ligaments
A
connect bones at joints
12
Q
bone
A
mineralized connective tissue
13
Q
osteoblasts
A
layers of bone-forming cells
• Synthesize collagen
14
Q
osteons
A
structural, repeating units which make up bone
• Each osteon has concentric layers
15
Q
adipose tissue
A
specialized connective tissue that stores fat in adipose cells
• Pads and insulates body and stores fuel as fat molecules
• Each fat droplet swells when fat is stored and shrinks when at is used
16
Q
cartilage
A
contains collagenous fibers embedded within a protein-carbohydrate complex called chondroitin sulfate
• Often replaced by bone in embryos as they mature
• Found in disks that cushion between vertebrae
17
Q
chondrocytes
A
cells which secrete collagen and chondroitin sulfate
Make cartilage strong and flexible
18
Q
blood
A
• Has extracellular matrix called plasma which contains water, salts, and dissolved proteins
19
Q
erythrocytes
A
red blood cells- found in plasma
• Carry oxygen
20
Q
leukocytes
A
white blood cells- found in plasma
21
Q
platelets
A
aid in blood clotting
22
Q
muscle tissue
A
responsible for all types of movement
o Consists of filaments containing the proteins actin and myosin which play a role in muscle contraction
23
Q
skeletal muscle (muscle tissue)
A
attached to bones by tendons
• Responsible for voluntary movement
24
Q
muscle fibers (skeletal muscle)
A
bundles of long cells
Form by fusion of cells, resulting in multiple nuclei
25
sarcomere (muscle fibers)
contractile units
| • Give the cells a striated appearance
26
smooth muscle
spindle-shaped cells
o Lacks striations
o Found in walls of digestive tract, urinary bladder, arteries, and other internal organs
o Responsible for involuntary body activities (ex. Churning of stomach, constriction of arteries)
27
cardiac muscle
forms contractile wall of the heart
o Striated with contractile units
o Fibers connected via intercalated disks which relay signals from cell to cell
28
nervous tissue
functions in receipt, processing, and transmission of information
• Information processing center
29
neurons (nerve cells)
transmit nerve impulses and support glial cells
| Receives nerve impulses from other neurons via cell body and dendrites
30
glial cells/glia
insulate, nourish, and replenish neurons, sometimes module neuron function
31
endocrine system
where signaling molecules released into the bloodstream by endocrine cells are carried to all locations throughout the body
o Well adapted to coordinating gradual changes such as growth, development, reproduction, metabolic processes, and digestion.
32
hormones
signaling molecules
| • Only cells that have receptors for a particular hormone respond
33
nervous system
where neurons transmit signals along dedicated routs connecting specific locations in the body
o Nervous system conveys information by the particular pathway the signal takes.
o Adapted for rapid responses to environment.
34
regulator
uses internal mechanisms to control internal change in the face of external fluctuation
35
conformer
allows its internal condition to change in accordance with external changes
36
homeostasis
‘steady state’, maintaining a relatively constant internal environment when external environment changes significantly
o Is a dynamic equilibrium- moderates, but does not eliminate changes in environment
o Normal blood glucose is 70-110 mg of glucose/100 mL blood
o Normal pH within 0.1 of 7.4
37
dynamic equilibrium
an interplay between external factors that change the internal environment and internal control mechanisms that oppose such changes
38
set point
a particular set value
39
stimulus
a fluctuation above or below the set point
| Ex: when a thermostat drops below a set point
40
response
a physiological activity that helps return the variable to the set point
41
control center
generates an output that triggers a response
42
negative feedback
control mechanism that reduces stimulus
43
positive feedback
control mechanism that amplifies rather than reduces the stimulus
o Help drive processes to completion (in humans)
44
circadian rhythm
a set of physiological changes that occur roughly every 24 hours
o Human body temperature rises and falls no more than .6ºC/1ºF every 24 hours
45
acclimatization
the process by which an animal adjusts to changes in its external environment
o Ex: Acclimatization to altitude: as an elk moves above sea level, lower O2 concentration stimulates the animal to breathe more rapidly. As a result, CO2 is lost through exhalation, raising blood pH above a normal level.
o Ex: Fish’s body produces antifreeze in 28ºF water
• Acclimatization causes animal to excrete more alkaline urine from kidneys, lowering blood pH to normal range
• This is a TEMPORARY change
46
thermoregulation
the process by which animals maintain their body temperature within a normal range
o Aims to make rate of heat gain equal rate of heat loss
47
endothermic
creatures that are warmed by heat generated by their metabolism
o Consist of humans and most mammals, birds, and small insects
48
ectothermic
gain most of their heat from external sources
o Consists of reptiles, fishes, and amphibians
o Having a largely environmental food source allows them to consume less food
o Can tolerate larger fluctuations in their internal temperature
49
poikilotherm
an animal whose body temperature varies with its environment
50
homeotherm
animal who has a relatively constant body temperature
51
radiation
emission of electromagnetic waves by all objects warmer than absolute zero
• Ex: lizard absorbs heat from the sun, radiates energy to the air
52
convection
transfer of heat by the movement of air or liquid past a surface
• Ex: breeze allows for heat loss on lizard when blood moves heat from body core to extremities
53
evaporation
removal of heat from the surface of a liquid that is losing some of its molecules as a gas
54
conduction
direct transfer of thermal motion (heat) between molecules of an object in contact with each other
• Ex: lizard transfers heat with rock it’s sitting on
55
integumentary system
outer covering of the body- consisting of skin, hair and nails
56
insulation (integumentary system)
thermoregulatory adaptation which reduces flow of heat between animal’s body and its environment
• Reduces overall heat exchange
• Ex: Raising feathers/fur traps thick layer of air
57
vasodilation
when nerve signals relax the muscles of the blood vessel walls, thereby widening blood vessels near the skin’s surface
• Causes increase in blood flow in the skin
• Warms skin in endotherms
58
vasoconstriction
reduces blood flow and heat transfer by decreasing diameter of superficial vessels
59
countercurrent exchange
transfer of heat (or solutes) between fluids that are flowing in opposite directions
o Arteries and veins are located adjacent to each other, but blood flows in opposite directions
• This allows for efficient heat exchange
o Enables vigorous, sustained activity in powerful swimming organisms
o Maintains high temperature in endothermic insects
60
thermogenesis
when endotherms vary heat production to match changing rates of heat loss
• Essentially increases metabolic heat production
• Increased by muscle activity such as moving or shivering
• Smallest insects contract flight muscles to generate energy/heat.
61
nonshivering thermogenesis
when certain hormones cause mitochondria to increase their metabolic activity and produce heat instead of ATP
62
brown fat (thermogenesis)
specialized for rapid heat production
63
hypothalamus
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contains group of nerve cells that function as a thermostat
o Sensors (‘ear thermometer’) activate mechanisms to promote heat loss or heat gain
o Warm sensors signal when temp. of blood increases, cold sensors signal when temp. decreases
• Below normal range: You will save heat by constricting vessels in the skin. You will generate heat by shivering.
• Above normal range: dilation of vessels in skin, sweating, and panting.
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64
bioenergetics
the overall flow and transformation of energy in an animal
o Determines nutritional needs
o Related to animal’s size, activity, and environment
65
autotrophs
harness light energy to build energy-rich organic molecules
| o Include plants
66
heterotrophs
obtain chemical energy from food
o The food consists of organic molecules synthesized by other organisms
o Include animals
o Chemical energy in food is used to fuel metabolism and activity
67
metabolic rate
the sum of all energy an animal uses in a given time interval
o Measured in J/cal/kcal/C(kilocalorie)
o Can be measured by monitoring animals rate of heat loss with calorimeter
o Can also be measured by recording rate of food consumption, energy content of food, and chemical energy lost in waste products
68
basal metabolic rate (BMR)
minimum metabolic rate of nongrowing endotherm that is at rest, has an empty stomach, and is not experiencing any stress
o Measured at a specific temperature
69
standard metabolic rate (SMR)
metabolic rate of a fasting, nonstressed ectotherm at rest at a particular temperature
70
torpor
a state of decreased activity and metabolism
| o Adaptation which allows animals to save energy while avoiding dangerous conditions
71
hibernation
long-term torpor that is an adaptation to winter cold and food scarcity
• Mammal’s body temp. decreases
• Circadian clock stops working
72
estivation
summer torpor
| • Enables organisms to survive on high temp. and scarce water
73
dendrites
cellular extensions which help neuron receive nerve impulses from other neurons
74
axons
cellular extensions which transmit impulses to neurons, muscles, or other cells
