1. Homeostasis and Endocrine Signaling

2. Tissues Figure 32.2 4 major types:
Epithelial – found on outside of the body and lining organs and cavities.
Muscle – 3 types
Cardiac – heart tissue, involuntary
Smooth – involuntary actions in body, organs, blood vessels
Skeletal – muscle that moves, attaches to bone, voluntary

3. Nervous tissue – the neuron, sends impulses, communication
Glia cells are nerve helping cells to the neurons
Connective tissue – diverse group of tissues scattered throughout body and extracellular matrix
Bone – calcified hard matrix
Blood – liquid matrix
Cartilage – ear, nose, gel like matrix
Dense fibrous – tendons and ligaments
Adipose - fat
Areolar – loose fibrous connecting tissue

4. Regulator or Conformer?
Animals that are regulators uses internal mechanisms to control internal change – endothermic, homeothermic, warm blooded
Animals that are conformers – internal condition changes in accordance with external changes, ectothermic, cold blooded
Homeostasis – maintenance of a constant internal balance
examples,- body temp, blood glucose levels…
Negative feedback – when body is out of homeostasis and it is brought back.
Positive feedback – when body is brought out of homeostasis purposely for a short period of time, childbirth and oxytocin

5. Thermoregulation (heat)
Figure 32.3

6. Sensor/ control center: Thermostat turns heater off. Response:
Figure 32.4
Sensor/
control center:
Thermostat
turns heater off.
Response:
Heating stops.
Room
temperature
decreases.
Stimulus:
Room
temperature
increases.
Set point:
Room temperature
at 20C
Figure 32.4 A nonliving example of temperature regulation: control of room temperature
Stimulus:
Room
temperature
decreases.
Room
temperature
increases.
Response:
Heating starts.
Sensor/
control center:
Thermostat
turns heater on. 6

7. Endocrine system
Endocrine system – communication via hormones that are released by endocrine glands into the blood stream.
Hormones – chemical messengers
Exocrine glands – figure 32.11
Exocrine glands – integumentary system, release product to cavity or outside the body, sweat.
Nervous system – rapid communication using neurons and nerve impulses
All run by Stimulus/Response mechanism

8. Major Endocrine Glands and Their Hormones Hypothalamus
Figure 32.11a
Major Endocrine Glands
and Their Hormones
Hypothalamus
Pituitary gland
Anterior pituitary
Pineal gland
Melatonin
Posterior pituitary
Oxytocin
Vasopressin
(antidiuretic
hormone, ADH)
Thyroid gland
Thyroid hormone
(T3 and T4)
Calcitonin
Adrenal glands
(atop kidneys)
Parathyroid glands
Parathyroid hormone (PTH)
Adrenal medulla
Epinephrine and
norepinephrine
Ovaries (in females)
Estrogens
Progestins
Figure 32.11a Exploring the human endocrine system (part 1: glands and hormones)
Adrenal cortex
Glucocorticoids
Mineralocorticoids
Testes
(in males)
Androgens
Pancreas
Insulin
Glucagon 8

9. Sensor/control center: Thermostat in hypothalamus Response: Sweat
Figure 32.8
Sensor/control center: Thermostat
in hypothalamus
Response: Sweat
Response:
Blood vessels
in skin dilate.
Stimulus:
Increased body
temperature
Body
temperature
decreases.
Homeostasis:
Internal body
temperature of
approximately
36–38C
Body
temperature
increases.
Stimulus:
Decreased body
temperature
Figure 32.8 The thermostatic function of the hypothalamus in human thermoregulation
Response:
Blood vessels
in skin constrict.
Sensor/control center: Thermostat
in hypothalamus
Response: Shivering 9

10. Endocrine cell Cell body of neuron
Figure 32.9
(a) Signaling by hormones
(b) Signaling by neurons
Stimulus
Stimulus
Endocrine
cell
Cell
body of
neuron
Nerve
impulse
Axon
Hormone
Signal
travels
everywhere.
Signal
travels to
a specific
location.
Blood
vessel
Nerve
impulse
Figure 32.9 Signaling in the endocrine and nervous systems
Axons
Response
Response 10

11. Osmoregulation (fluids)
How animals control solute concentrations in the interstitial fluid and balance water gain and loss
Excretory system – releasing of nitrogenous and metabolic waste products (kidney)
Osmoconformer – being isoosmotic with its surroundings, marine animals
Osmoregulator – to control internal osmolarity independent of the environment. Allows animals to live in freshwater/terrestrial habitats.

12. Nitrogenous wastes in animals
32.16

13. Proteins Nucleic acids Amino acids Nitrogenous bases Amino groups
Figure 32.16
Proteins
Nucleic acids
Amino
acids
Nitrogenous
bases
Amino groups
Most aquatic
animals, including
most bony fishes
Mammals, most
amphibians, sharks,
some bony fishes
Many reptiles
(including birds),
insects, land snails
Figure Forms of nitrogenous waste
Ammonia
Urea
Uric acid 13

14. Most aquatic animals, including most bony fishes Mammals, most
Figure 32.16a
Most aquatic
animals, including
most bony fishes
Mammals, most
amphibians, sharks,
some bony fishes
Many reptiles
(including birds),
insects, land snails
Figure 32.16a Forms of nitrogenous waste (detail)
Ammonia
Urea
Uric acid 14

15. The excretory process
Urine formation: 32.17

16. Filtration Capillary Filtrate Excretory tubule Reabsorption Secretion
Figure 32.17
Filtration
Capillary
Filtrate
Excretory
tubule
Reabsorption
Figure Key steps of excretory system function: an overview
Secretion
Urine
Excretion 16

17. The Kidney – figure 32.19

18. Kidney Structure Nephron Organization Nephron Types Renal cortex
Figure 32.19b
Kidney Structure
Renal cortex
Renal medulla
Renal artery
Nephron Organization
Renal vein
Afferent arteriole
from renal artery
Glomerulus
Bowman’s
capsule
Ureter
Proximal
tubule
Renal pelvis
Peritubular
capillaries
Distal
tubule
Nephron Types
Cortical
nephron
Efferent
arteriole
from
glomerulus
Figure 32.19b Exploring the mammalian excretory system (part 2: kidney structure summary)
Branch of
renal vein
Descending
limb
Renal
cortex
Loop of
Henle
Vasa
recta
Collecting
duct
Renal
medulla
Ascending
limb
Juxtamedullary
nephron 18

19. Nephron Organization Afferent arteriole from renal artery Glomerulus
Figure 32.19bc
Nephron Organization
Afferent arteriole
from renal artery
Glomerulus
Bowman’s
capsule
Proximal
tubule
Peritubular
capillaries
Distal
tubule
Efferent
arteriole
from
glomerulus
Branch of
renal vein
Figure 32.19bc Exploring the mammalian excretory system (part 2c: nephron organization)
Descending
limb
Loop of
Henle
Vasa
recta
Collecting
duct
Ascending
limb 19

20. Salts (NaCI and others) HCO3− OUTER MEDULLA H Urea Thin segment
Figure 32.20 1
Proximal tubule 4
Distal tubule
NaCI
Nutrients
H2O
HCO3−
H2O K
NaCI
HCO3− H
NH3 K H
Interstitial
fluid
CORTEX 3
Thick segment
of ascending
limb 2
Descending limb
of loop of
Henle
Filtrate
H2O
Salts (NaCI and others)
NaCI
H2O
HCO3−
OUTER
MEDULLA
NaCI H
Urea
Figure The nephron and collecting duct: regional functions of the transport epithelium 3
Thin segment
of ascending
limb 5
Collecting
duct
Glucose, amino acids
Some drugs
Urea
NaCI
H2O
Key
Active transport
INNER
MEDULLA
Passive transport 20

21. Adaptations
Based on where you live, there are adaptations to the kidney
Hyperosmotic urine (dessert animals) – long loops of Henle that extend deep into the medulla
Birds – shorter loop of Henle, les concentrated urine compared to mammals – uric acid is product to help conserve water.

22. Homeostatic regulation of kidney
32.23 antidiruretic hormone

23. Osmoreceptors trigger release of ADH. Thirst Drinking ADH of fluids
Figure
Osmoreceptors
trigger release
of ADH.
Thirst
Drinking
of fluids
ADH
Increased
permeability
Distal
tubule
STIMULUS:
Increase
in blood
osmolarity
Figure Regulation of fluid retention in the kidney by antidiuretic hormone (ADH) (step 3)
H2O
reabsorption
Collecting duct
Homeostasis 23