Mammals
Classification
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Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrates
Class: Mammalia
• 20 different Orders
• 4400 Species
– Very diverse class
– Live on every continent & in
every ocean
Key Mammalian
Characteristics
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1. Endothermic:
– Warm-blooded
• Can live in any climate
• Regulate internal
temperature
• VERY ACTIVE
Key Mammalian
Characteristics
•
1. Endothermic:
– Subcutaneous fat(under our skin)
– Form insulation
– Protection of internal organs
Key Mammalian
Characteristics
•
1. Endothermic:
– Sweat glands or panting, shedding
– To cool down
Key Mammalian
Characteristics
2. Hair/Fur
– Insulation
– Camouflage
– Protection
Key Mammalian
Characteristics
3. Completely divided
4 chambered heart
– Has a complete
septum
• Very efficient heart
b/c clean & dirty
blood never mix
Key Mammalian
Characteristics
4.
Milk production
(mammary glands)modified sweat glands
– Used by the female
to feed young
– Teats (provide milk
from mammary
glands)
Key Mammalian
Characteristics
4. Milk production
Milk contains:
• Protein
• Vitamins
• Fat
• Calcium (sm. amt.)
• Water
Key Mammalian
Characteristics
5.Single Jawbone
– Lower jawbone is
single
1
1
6. Specialized Teeth
• Back teeth:
chewing, grinding,
crushing, slicing
• Molars: grind food
• Pre-molars: grind
food
6. Specialized Teeth
• Front Teeth: biting,
cutting, seizing prey
• Canines: grip &
puncture prey
• Incisors: to cut
• 1st place physical
digestion occurs
Teeth and Skull
Did you know that
bone is 5X stronger
than steel?
Teeth and Skull
History of Mammals
• Evolved from mammal-like reptiles
• Mammals & dinosaurs evolved @
same time (mice-size)
• Once dinos went extinct
– most successful at finding food
– became larger
Monotremes
• Oviparity
– Egg layers
– lay 1-2 leathery
eggs per year
– feeds off yolk of egg
– mammary glands
• Live in New Guinea
and Australia
Marsupials
• 280 species of
marsupials
– Ex. Opossum (live in
US), kangaroo, koala
• Viviparity
– Give birth to live young
– Develop in uterus(sm
period of time)
– Under-developed young
crawl out of vagina into
pouch where they feed
off teats
Placental
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•
19 orders of placental animals
Viviparity
– Give birth to live younguterus, placenta, umbilical
cord (provides nourishment
to fetus from mother)
– Gestation period (time it
takes for full fetal
development)
– Cared for by parents
– Fed w/ mammary glands
until old enough to feed on
own
Gestation Periods
Digestive System – Write Small
**More Info in Unit Review**
• To break down food into
useable molecules=
carried to cells via blood
• 1) Mouth-teeth physical
digestion
• 2) Salivary glands
– Produce saliva
– Contains enzyme
amylase
• Chemical digestion
of carbohydrates
Digestive System
• 3) Esophagus
– Passageway for food from mouth to stomach
– peristalsis: Wave-like motion that pushes food to
stomach
• 4) Cardiac Sphincter
– End of esophagus, beginning of stomach
– Ring of muscle
– Keeps food moving in 1 direction
– “heart burn” if food moves back
into esophagus from sphincter
Digestive System
• 5) Stomach
– Muscular sac which
digests proteins
– Physical digestion in
form of churning
– Chemical in form of HCl
+ pepsin to break down
proteins
– Special lining to protect
from acid; can lead to
ulcer
– Chyme- undigested
food+enzyme+acid
Stomach
Digestive System
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6) Pyloric Sphincter
– Ring of muscle which
keeps food moving from
stomach to sm. intestine
7) Small Intestine
– ~20-21 ft. long
– 3 sections
– Duodenum: 10“ carries
chyme to jejunum
– Jejunum: 8’ carbs,
proteins, lipids digestion;
absorbed into blood
– Ileum: 13’ takes
undigested material to
large intestine
– Has villi
Villi in Small Intestine
-Villi increases surface area
Digestive System
• 8. Large Intestine
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–
–
larger diameter
3 ft. long
to remove excess water
too much water
absorbed=constipation
– too little water
absorbed=diarrhea
• 9. Rectum & Anus
– holds solid waste until
expelled (rectum)
– exit (anus)
Caecum/Appendix
• Caecum-pig
– “dead-end”
– Helps digest plant material
• Appendix-humans
– No apparent function
Rumen
• Sheep, cows
• Regurgitate-cud
Digestive SystemAccessory Organs
• Gall bladder
– Stores bile: for the
digestion of lipids
• Pancreas– pancreatic amylasecarbs
– lipase-lipids
– pepsinogen- proteins
– sends these enzymes to
small intestine
(don’t pass thru)
Liver
Gall Bladder Under Liver
Stomach and Pancreas
Pancreas
To Digest…
1.
2.
3.
4.
5.
6.
7.
Ingest
Chew 10 to 30 times
Swallow 4 to 8 seconds
Churn 2 to 4 hours
Absorb 3 to 5 hours
Compact 10 hours to several days!
Eliminate
Respiratory System
**more info in unit review**
• To transports O2 and
CO2 from atmosphere
to the cells
• Two types
– External: air thru
nose to lungs
– Internal: gases w/ in
blood are exchanged
w/ cells
Respiratory System
• Nostrils/Nares- with
hair to trap particles
• Pharynx- food & air
• Epiglottis small flap
to separate food & air
passage
• Trachea- made of rings of
cartilage so it doesn’t collapse
“windpipe”
Salivary Glands and Larynx
Trachea
Respiratory System
• Bronchi-lead to lungs
• Bronchioles- little
tubes
• Alveoli- little air sacs
• Pleura
– Secretes slippery fluid to
reduce friction
– Surrounds the lungs
Respiratory System
Respiratory System
Respiratory System
• What happens when you run & it’s cold
outside?
Avg. Pack of Cigarettes
Circulatory System
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Heart is main organ
– Veins-carry blood to heart
– Arteries-carry blood away
from heart
Heart lies in center of chest/
thoracic cavity btw. lungs
– Underneath sternum(breast
bone)
4 chambers
– 2 sides
– Divided by a complete
septum
Spleen-destroys or recycles
old red blood cells
Liver and Spleen
Circulatory System
• Right
– Pumps dirty blood
(CO2) to lungs
– pulmonary
• Left
– Pumps clean blood
(O2) to body
– systemic
60,000 miles of blood vessels
STUDY blood pathway paragraph in notes!!
Pulmonary Artery
Pulmonary Vein
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
Superior Vena Cava
Pulmonary Artery (dO2 blood) to Lungs
Pulmonary Vein (O2 blood) from Lungs
Right Atrium
Tricuspid Valve
Semilunar Valves (Pulmonary & Aortic)
Inferior Vena Cava
LABEL HEART
Right Ventricle
DIAGRAM
Septum
Left Ventricle (MOST MUSCULAR-PUMP)
Bicuspid/Mitral Valve
Left Atrium
Aorta
Male Posterior View
Female Posterior view
Nervous System
• See
Notesheet
Unfolded Brain Surface Area=1m2
Average Brain Weighs= 3 lbs
Excretory System
• To filter out and
eliminate metabolic
wastes and help
maintain homeostasis
– Gets rid of excess H2O ,
salt, vitamins, toxins,
minerals, and heat
– Nitrogenous Waste:
ammonia converted to
urea in liver
Excretory System
• 2 kidneys-reddish bean
shaped organ
– Size of a clenched fist
– Lie along in small of
back
Structure of a nephron
• Each kidney is made
up of one million+
nephrons (filtering unit)
• Blood enters kidney via
the renal artery
• Blood is pushed
through a nephron
where excess H2O,
salt, toxins, minerals,
urea is filtered out.
Structure of a nephron
• Blood enters the
bowman's capsule
• Capsule filled w/
glomerulus( ball of
blood vessels)
• all substances are
filtered out
• Cleaned blood reenters
cir. system
Structure of a nephron
• Impurities travel along the renal tube
• Some items reenter blood; impurities
empty into the renal pelvis
3 Main Parts of a Kidney
• 3-parts
– Cortex-outer
portion of kidney
– Medulla-inner
region
– Renal pelvishollowed out
area where all
waste gathers.
Urine Formation
• All nephrons empty into
renal pelvis
• Renal pelvis empties
into the
ureter(1/kidney)
• Ureter leads to bladder
and urine exits out the
urethra
Urine Formation
• Average Adult:
– ~1.5-2.3 Liters/day
– Greatest amount of water loss
• Must urinate 500mL to get rid of
toxins
**See Notes for Repro**
Male or Female?!?
Smallest Cell in Body
Largest Cell in Body
½ Hour as a Single Cell
Heart of the Embryo…
Beats at 3 weeks!!!!
All organs by 9 weeks…
Eye Size= SAME!!!
Skin weighs 9 lbs!!!
Muscle Mass:
-1/2 Men
-1/4 Women
1 month to replace ALL skin cells
Bone=matrix of hard minerals