Homeostasis and Endocrine Signaling - PowerPoint Presentation

Slide1

Homeostasis and Endocrine Signaling

Slide2

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

Slide3

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

Slide4

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

Slide5

Thermoregulation (heat)

Figure 32.3

Slide6

Figure 32.4

Sensor/

control center:

Thermostat

turns heater off.

Sensor/

control center:

Thermostat

turns heater on.

Stimulus:

Room

temperature

increases.

Stimulus:

Room

temperaturedecreases.

Roomtemperatureincreases.

Roomtemperaturedecreases.

Set point:Room temperatureat 20C

Response:Heating stops.

Response:

Heating starts.

Slide7

Endocrine system

Endocrine system

– communication via hormones that are released by endocrine glands into the blood stream.

Hormone

s – 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

Slide8

Figure 32.11a

Pancreas

Insulin

Glucagon

Testes

(in males)

Androgens

Parathyroid glands

Parathyroid hormone (PTH)

Ovaries (in females)

Estrogens

Progestins

Thyroid gland

Thyroid hormone

(T

3

and T4)Calcitonin

Pineal glandMelatonin

Major Endocrine Glandsand Their Hormones

Hypothalamus

Pituitary gland

Anterior pituitary

Posterior pituitary

Oxytocin

Vasopressin

(antidiuretic

hormone, ADH)

Adrenal glands

(atop kidneys)

Adrenal medulla

Epinephrine and

norepinephrine

Adrenal cortex

Glucocorticoids

Mineralocorticoids

Slide9

Figure 32.8

Sensor/control

center: Thermostat

in hypothalamus

Stimulus:

Decreased body

temperature

Body

temperature

increases.

Body

temperature

decreases.

Homeostasis:

Internal body

temperature of

approximately36–38C

Response:Blood vesselsin skin dilate.

Response: Shivering

Sensor/controlcenter: Thermostatin hypothalamus

Response:

Blood vessels

in skin constrict.

Stimulus:

Increased body

temperature

Response: Sweat

Slide10

Figure 32.9

Cell

body of

neuron

Response

Hormone

Nerve

impulse

Signal

travels

everywhere.

Signal

travels to

a specific

location.

Response

Stimulus

Stimulus

Nerve

impulse

Blood

vessel

Endocrine

cell

(a) Signaling by hormones

Axons

Axon

(b) Signaling by neurons

Slide11

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.

Slide12

Nitrogenous wastes in animals

32.16

Slide13

Figure 32.16

Most aquatic

animals, including

most bony fishes

Proteins

Nucleic acids

Amino

acids

Nitrogenous

bases

Amino groups

Mammals, most

amphibians, sharks,

some bony fishes

Many reptiles

(including birds),

insects, land snails

Ammonia

Urea

Uric acid

Slide14

Figure 32.16a

Most aquatic

animals, including

most bony fishes

Mammals, most

amphibians, sharks,

some bony fishes

Many reptiles

(including birds),

insects, land snails

Ammonia

Urea

Uric acid

Slide15

The excretory process

Urine formation: 32.17

Slide16

Figure 32.17

Capillary

Filtration

Excretory

tubule

Filtrate

Reabsorption

Secretion

Urine

Excretion

Slide17

The Kidney – figure 32.19

Slide18

Figure 32.19b

Kidney Structure

Renal cortex

Nephron Organization

Nephron Types

Renal medulla

Renal artery

Renal vein

Renal pelvis

Ureter

Renal

cortex

Renal

medulla

Cortical

nephron

Juxtamedullary

nephron

Collecting

duct

Branch of

renal vein

Vasa

recta

Efferent

arteriole

from

glomerulus

Distal

tubule

Afferent arteriole

from renal artery

Glomerulus

Bowman

’

s

capsule

Proximal

tubule

Peritubular

capillaries

Descending

limb

Ascending

limb

Loop

of

Henle

Slide19

Figure 32.19bc

Nephron Organization

Collecting

duct

Branch of

renal vein

Vasa

recta

Efferent

arteriole

from

glomerulus

Distal

tubule

Afferent arteriole

from renal artery

Glomerulus

Bowman

’

s

capsule

Proximal

tubule

Peritubular

capillaries

Descending

limb

Ascending

limb

Loop

of

Henle

Slide20

Figure 32.20

Filtrate

OUTER

MEDULLA

H

2

O

Salts (NaCI and others)

HCO

3

−

Glucose, amino acids

H



Some drugs

Passive transport

Active transport

Key

INNER

MEDULLA

CORTEX

Descending limb

of loop of

Henle

H

2

O

Interstitial

fluid

NH

3

H



Nutrients

HCO

3

−

K



NaCI

Proximal tubule

H

2

O

Thick segment

of ascending

limb

H



Urea

HCO

3

−

K



NaCI

Distal tubule

H

2

O

Thin segment

of ascending

limb

NaCI

H

2

O

NaCI

NaCI

Collecting

duct

1

2

3

5

4

3

Urea

Slide21

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.

Slide22

Homeostatic regulation of kidney

32.23

antidiruretic

hormone

Slide23

Figure 32.23-3

Distal

tubule

H

2

O

reabsorption

STIMULUS:

Increase

in blood

osmolarity

Drinking

of fluids

Increased

permeability

Osmoreceptors

trigger release

of ADH.

Thirst

ADH

Collecting duct

Homeostasis