Download Organization and Regulation of Human Body Systems Digestion, Excretion, Skeletal Muscular

Organization and Regulation
of Human Body Systems
Digestion, Excretion, Skeletal
Muscular
Major Components:
Accessory Organs:
MOUTH: chewing and 1st
site to digest starch)
PHARYNX
SALIVARY GLANDS
(makes amylase)
ESOPHAGUS
STOMACH (churning
and 1st chemical
digestion of protein)
SMALL INTESTINE
(main site of
nutrient absorption
LARGE INTESTINE
(COLON) (removes
waste and retrieves
water)
LIVER (makes bile,
detoxes drugs and
other substances)
GALLBLADDER
(stores bile for SI)
PANCREAS (make
Insulin and Glucagon
Makes enzymes for SI)
RECTUM (storage)
ANUS
Fig. 36-5, p.614
Table 36.4 Summary of the Human Digestive System
Mouth
Start of digestive system, where food is chewed,
(oral cavity) and moistened; starch digestion begins
Pharynx
Entrance to digestive and respiratory tract tubes
Esophagus Muscular tube, moistened by saliva, that moves food from pharynx to
stomach
Stomach
Stretchable sac where food mixes with gastric fluid and protein
digestion starts; stores food taken in faster than can be processed; its
fluid kills many microbes
Small
intestine
Receives secretions from liver, gallbladder, pancreas; digests most
nutrients; delivers unabsorbed material to colon
Colon
(large
intestine)
Concentrates and stores undigested matter (by absorbing mineral ions
and water)
Rectum
Distension triggers expulsion of feces
Anus
Terminal opening of digestive system
Table 36-4, p.628
8.3 The stomach and small intestine
What are the major digestive enzymes?
Know the role of and source of each of the following: bile
amylase, maltase, pepsin, trypsin,nuicleases, lipase.
8.3 The stomach and small intestine
How are nutrients digested and transported
out of the small intestine?
Proteases: pepsin and trypsin
Sucrase, Lactase, Cellulase, Chitinase,
Lipases, Nucleases
What are 2 steps in the digestion of lipids?
SMOOTH MUSCLES LINE THE DIGESTIVE TRACT AND
USE WAVELIKE CONTRACTIONS
Called “PERISTALSIS”
Fig. 36-8c, p.617
MILK, CHEESE, YOGURT : Two servings/day (three/day for teenagers or pregnant, lactating, post-menopausal women)
ADDED FATS AND SIMPLE SUGARS. Other foods have plenty. Restrict intake of butter, salad dressings, sweets, soft
drinks, snacks
VEGETABLES: (2.5 CUPS /DAY
FRUITS : Two to four servings/day (2 CUPS/DAY)
LEAN MEAT, POULTRY, FISH, LEGUMES, EGGS: Two to three servings/day (serving size is a deck of cards)
GRAIN PRODUCTS (BREADS, CEREALS, PASTA) : Six to eleven servings/day 6 oz, serving size is ½ cup
DIETARY REQUIREMENTS:
You need to get the following in your diet..
Fat Soluble Vitamins: D, E, A, K
Water Soluble Vitamins: (Several B, Folate, Biotin, C)
Minerals (12): Ca, Cl, Co, F, I, Fe, Mg, Na, P, K, S, Zn)
Proteins, Carbohydrates, Lipids, Nucleic Acids
One needs to consume between 1500 and 2500 calories
Daily depending on gender, height, activity.
FOUR ORGANS OF THE URINARY SYSTEM
KIDNEYS
Constantly filters water
and all solutes except proteins from
blood; reclaims water and solutes as
the body requires and excretes the
remainder, as urine
One million nephrons are in each
kidney.
URETER (one of a pair)
Channel for urine flow from a
kidney to the urinary bladder
BLADDER: Stretchable
container for temporarily Storage
of urine
URETHRA:
Channel for
urine flow between the urinary
bladder and body surface
adren
al
gland
SUMMARY OF EXCRETORY OR URINARY SYSTEM
How do the kidneys maintain
homeostasis?
Excrete wastes: REMOVES AMMONIUM WASTE
Urea, creatinine and uric acid
Water-salt balance of blood: OSMO & THERMAL REGULATION
Helps regulate blood volume and pressure
Acid-base balance of blood: BLOOD CHEMISTRY
Helps regulate pH
Assistance to other systems
Endocrine, cardiovascular, skeletal, muscular
nervous and digestive
Fig. 37-6, p.635
How does the nephron form urine?
NEPHRON IS FUNDAMENTAL
UNIT OF THE KIDNEY
Four Steps to Processing
Blood
1.
2.
3.
4.
5.
Bowman’s Capsule
Filtration of Blood
happens in
Proximal tubule
Reabsorption, returns
wanted solutes and water
to blood
Distal tubule, Secretion
moves solutes from blood
directly into the Nephron
Collecting duct Hormone
ADH binds to the if water
must be conserved in the
body.
Unwanted water, urea,
salts, NH4 and creatine
are urinated from the
body
Endocrine Glands Regulate Sexual
and Non-Sexual Functions
Hormones secreted
by gland travel to
target site:
Hypothalamus :
GnRH regulates the Pituitary
Pituitary gland regulates
other glands:
ACTH: adrenal
HGH: bone length
TSH: thyroid
PRL: milk production
FSH & LH: sexual function
Oxytocin: uterine contractions
ADH: kidney, water loss
15.2 Hypothalamus and pituitary gland
The hypothalamus and pituitary
KIDNEY FUNCTION
DEPENDS ON
NEPHRONS
ADH IS ANTIDIURETIC
WILL DECREASE
URINE VOLUME
CAFFEINE
ALCOHOL
Skeletal system
1. Supports the body
2. Protects the soft body
parts
3. Produces blood cells
(red bone marrow)
4. Stores minerals
(calcium and
phosphate) and fat
5. Allows for movement
by attaching muscles
Skeletal System Uses 2 types of Supportive Connective Tissue
Cartilage and Bone. Ends of bones are coated in cartilage,
cartilagenous disc are found in between 2 vertibrae, ears and
nose are made of cartilage.
cartilage on
knobby end
of a long
bone
4. Cartilage (chondro)
5. Bone (Osteo)
• Cartilage is a solid but pliable
intercellular material contains
collagen and elastin protein
compact
bone tissue
spaces
in spongy
bone tissue
• Bone is ossified or calcified
connective tissue made of
collagen protein embedded with
minerals. Stores Ca and
Phosphorus in collagen matrix.
Bone has most rigid matrix
Inorganic salts are deposited around
protein fibers
Osteocyte
• Compact bone: makes up shaft
One Osteon is a cylindrical unit with nerve
and blood vessels. Cell connections are
canaliculi .
Osteocyte is a bone cell.
• Spongy bone: makes up the
ends of long bones. Blood cells
are made in red bone marrow
found in S.B. Calcium recycling
is done in spongy bone.
6. Blood is one type of Fluid CT
Includes 3 types of cells floating in fluid called plasma
• Classified as a connective
tissue because blood cells
arise in bone
• Transports nutrients, waste
and O2.
• Formed Elements (Red cells,
white cells, and platelets) are
dispersed in a fluid medium
called plasma
Formed Elements
• Erythrocytes: RBC, Transport O2, and CO2
don’t have nuclei are biconcave, most
abundant,
• Leukocytes: WBC, nave nucleus, are
translucent, fight infection. Many types with
specific functions. Most diverse:
)
• Thrombocytes: platelets are responsible for
blood clotting
Muscle Tissue (Myo)
• Composed of cells called fibers that contract
when stimulated
• Fiber cells are filled with protein filaments
(actin and myosin)
Three Types of Muscle
• Skeletal muscle
• Smooth muscle
• Cardiac muscle
Skeletal Muscle
• muscles attached to bones by tendons
• Striations are the sarcomeres; use
actin and myosin proteins
• Voluntary, striated, not branched
• Cell fibers are multinucleated
• Osteoporosis – bones are weakened due to a
decreased bone density.
Factors affecting bone growth
 Growth hormone (GH) – stimulates
general bone growth and the epiphyseal
plates
 Sex hormones – increases growth during
adolescence
 Vitamin D – converted to a hormone to
allow calcium absorption in the intestine
 Calcium in Blood affects bone growth
through hormones:
 Parathyroid hormone (PTH) –
increases blood calcium by
accelerating bone recycling
 Calcitonin – decreases blood calcium
The Muscular System smallest
working unit is the sarcomere
Sarcomere has 2 types of
protein
Thick band made Myosin
Thin band made of actin
11.2 Bone growth, remodeling and repair
What are the important cells in bone growth,
remodeling and repair?
• Osteoblasts – bone-forming cells. Happens when body stores
Calcium, Stimulated by Calcitonin. Increases bone density
• Osteocytes – mature bone cells that maintain bone structure derived
from osteoblasts
• Osteoclasts – bone-absorbing cells. Happens when body needs
Calcium, Stimulated by parathyroxin. Decreases bone density
• Chondroytes – cartilage-forming cells
Bone Marrow
Yellow marrow
Fills the cavities of adult long bones
Is largely fat
Red marrow
Occurs in spongy bone of some bones
Produces blood cells
Long Bone Formation
Embryo: cartilage model of future bone in embryo
Fetus: blood vessel invades model; osteoblasts
start producing bone tissue; marrow cavity
forms
Newborn: remodeling and growth
continue; secondary bone-forming
centers appear at knobby ends of bone
Adult: mature bone
Bone Remodeling
In adults, bone building and bone breakdown continue constantly involves
Calcium storage
Osteoblasts forms bone, to remove Calcium from blood. Increases bone
density. Calcitonin hormone action, made by the thyroid gland
Osteoclasts degrades bone to release calcium and return it to blood.
Decreases bone density. Parathyroid hormone action made by
parathyroid gland
Remodeling adjusts bone strength and helps maintain blood calcium levels
Bone Density
Exercise can increase bone density
Osteoporosis is a decrease in bone
density
May occur when the action of osteoclasts
outpaces that of osteoblasts
May also occur as a result of inability to
absorb calcium
Joints
Arthritis is a Joint Disorder
Areas of contact or near contact between
bones
Fibrous joints
Short connecting fibers join bones
Synovial joints
Move freely; ligaments connect bones
Cartilaginous joints
Straps of cartilage allow slight movement
Skeletal Muscle
Bundles of striped muscle cells
Attaches to bone
Often work in opposition
biceps
Joints are areas of contact or
near contact between bones
Arthritis is a joint disorder
triceps
Skeletal Muscle Structure
A muscle is made up
of muscle cells
A muscle fiber is a
single muscle cell
Each fiber contains
many myofibrils
myofibril
Sarcomere is the unit of
contraction of a skeletal muscle
A myofibril is made up of thick and thin
filaments arranged in sarcomeres. Thick
filament is myosin, the thin filament is actin
protein.
sarcomere
sarcomere
Z band
sarcomere
sarcomere
Z band
Z band
Muscle Microfilaments
Thin filaments
Like two strands of
pearls twisted
together
Pearls are actin
Other proteins in
grooves in filament
Thick filaments
• Composed of myosin
• Each myosin
molecule has tail and
a double head
Sliding-Filament Model
Sarcomere shortens because the actin
filaments are pulled inward, toward the
sarcomere center
Sliding-Filament
Model for muscle
contraction
Myosin heads attach to actin
filaments
Myosin heads tilt toward the
sarcomere center, pulling actin
with them
Actin filaments moves while
myosin filaments are stationary
Muscles need a source of Energy (
ATP) and Calcium
Nervous System
Controls Contraction
Signals from nervous system
travel along spinal cord, down
a motor neuron
Neuron stimulates the release of
the Acetylcholine, this
activates a muscle
contraction
Endings of motor neuron
synapse on a muscle cell at a
neuromuscular junction
12.3 Whole muscle contraction
3 Pathways for
Acquiring ATP for
muscle contraction
•
Limited amounts of ATP are stored in muscle fibers
•
Creatine phosphate pathway (CP) – fastest way to acquire ATP but only
sustains a cell for seconds; builds up when a muscle is resting
•
Fermentation – fast-acting but results in lactate build up
•
Cellular respiration (aerobic) – not an immediate source of ATP but the best
long term source