Lecture 18 coordination, communication and homeostasis

Question 1

What makes up organs

Answer 1

Tissues (specialized cells organized into tissues)

Question 2

4 main categories of animal tissues

Answer 2

1. Epithelial tissues
2. Connective tissues
3. Nervous tissues
4. Muscular tissues

Question 3

Epithelial tissue

Answer 3

Covers the outside of the body and lines the organs and cavities w/in the body.

The cells are closely joined together

The shape of the cells can be cuboidal (like dice), columnar (like bricks on end),
or squamous (like floor tiles)

Question 4

What does Connective tissue do

Answer 4

Hold organs and tissue together

Question 5

What causes muscle tissue to have contractions

Answer 5

Myosin protein - muscle contraction

Question 6

Skeletal muscle

Answer 6

-attatched to bones by tendons
-is responsible for voluntary movement
-consist of bundles of large cells called muscle fibers
-building muscle increases size but not amount of muscle fibers

Question 7

Smooth muscle

Answer 7

-lacks striations
-found in the walls of the digestive tract, urinary bladder, arteries, etc
-cells are spindled shaped
-responsible for involuntary body activities (churning of the stomach and constrictions of arteries)

Question 8

Cardiac muscle

Answer 8

-forms the contractile wall of the hearts
-striated like skeletal muscle and has similar contractile properties
-has branched fibers that interconnect via intercalated disks; they relay signals from cell to cell and help synchronize heart contraction

Question 9

Nervous tissue

Answer 9

● Receive, process and transmit information
● Neurons and glial cells

Question 10

Nervous tissue (brain and spinal cord)

Answer 10

Central Nervous System (CNS)

Question 11

Nervous tissue (nerves)

Answer 11

Peripheral Nervous System (PNS)

Question 12

Examples of how the body exchanges with the environment

Answer 12

Exchange with the environment
(ex. respiratory system, excretory system, digestive system)

Question 13

In order to maintain homeostasis what does it require?

Answer 13

energy/atp

Question 14

Bioenergetics

Answer 14

-overall low and transformation of energy in animals
-determines animals overall nutrition need, and it relates to an animals size, activity, and environment

Question 15

Metabolic rate

Answer 15

the sum of all the energy an animal uses in a unit of time

Question 16

Metabolic rate can be determined by…

Answer 16

● An animal’s heat loss
● The amount of oxygen consumed or carbon dioxide
produced
● Measuring energy content of food consumed and energy
lost in waste products

Question 17

Size and metabolic Rate (BMR)

Answer 17

Same species: Metabolic rate is proportional to body
mass to the power of three-quarters (m3/4).

Different species
Smaller animals have
higher metabolic rates
per kilogram than larger
animals.

Question 18

Miscommunication within body

Answer 18

Diabetes Mellitus
Miscommunication between pancreas and glucose storage tissues (Liver and muscles).

Lou Gehrig’s disease (ALS)
No communication between the brain and muscles

Venoms
King Cobra venom blocks communication to muscles

Question 19

endocrine system (coordination and control)

Answer 19

● The endocrine system releases
signaling molecules called hormones
into the bloodstream
● A hormone may affect one or more
regions throughout the body
● Hormones are relatively slow acting,
but can have long-lasting effects

Question 20

The nervous system

Answer 20

● The nervous system transmits
information between specific locations
● The information conveyed depends on a
signal’s pathway, not the type of signal
● Nerve signal transmission is very fast

Question 21

Mechanisms of homeostasis

Answer 21

Mechanisms of homeostasis moderate changes in the international environment

For a given variable, fluctuations above or below a set point serve as a stimulus; these are detected by a sensor.

A control center then generates output that triggers a response.

The response returns the variable to the set point.

Question 22

Positive feedback

Answer 22

amplifies a stimulus and does not
usually contribute to homeostasis in animals.

Question 23

Negative feedback

Answer 23

helps to return a variable to a
normal range. (animals relies largely on this)

Question 24

Negative feedback loops in Homeostasis

Answer 24

The dynamic equilibrium of homeostasis is maintained by negative feedback, which helps to return a variable to a normal range. (think of shivering and sweating example)

Question 25

Thermoregulation

Answer 25

is the process by which animals maintain an internal temperature within a normal range.

(shivering and sweating)

Question 26

Homeostasis

Answer 26

used to maintain a “steady state” or internal balance regardless of external environment

body temp, blood pH and glucose conc are each maintained at a constant level

Question 27

Endothermic (Endothermy)

Answer 27

animals generate heat by metabolism; birds and mammals are endotherms

Question 28

Ectothermic (Ectothermy)

Answer 28

animals gain heat from external sources; ectotherms include most invertebrates, fishes,
amphibians, and nonavian reptiles

Question 29

Endothermy vs Ectothermy

Answer 29

● Endotherms can maintain a stable body temperature even in the face of large fluctuations in environmental temperature.
● Endothermy is more energetically expensive than ectothermy.
● In general, ectotherms tolerate greater variation in internal temperature.

Question 30

Alternations in Homeostasis

Answer 30

Set points and normal ranges can change with age or show cyclic variation.

In animals and plants, a circadian rhythm governs physiological changes that occur roughly every 24 hours.

Question 31

Acclimatization

Answer 31

Homeostasis can adjust to changes in external environment with this process

Acclimatization is a temporary change during
an animal’s lifetime.

Question 32

Adaptation

Answer 32

when some heritable traits aid in survival, individuals with this trait will produce more offsprings that survive as well and will pass on this trait, increasing the frequency of these traits in the next generation