Animal Science
AgriScience 1
Unit 26
Structure and Function
Animal Structures and Function
Animals are composed of a variety of
interdependent systems
 No one system can function entirely on its
own
 In order to keep animals healthy,
producers make sure that all systems
function properly.

Skeletal System

Function
 Provides
frame and support for all systems
and organs.

Cartilage
 Firm,
bone
flexible tissues that is not as hard as
Skeletal System
 Bone
Attach
muscles
Means of movement
Protect internal organs
Storage of minerals
Skeletal System
 Layers
of Bone
Periosteum
Outer layer
 Cushions the hard portion of
the bone
 Repair of broken bones

Skeletal System
 Layers
of Bone
Compact
Bone
beneath periosteum
 layer of hard mineral matter
 Calcium
 gives bones strength

Skeletal System
 Layers
of Bone
Spongy
Bone
Inside hard outer layer
 fills ends of bones
 lines hollow portions

Skeletal System
 Layers
Red
of Bone
marrow
inside cavities of spongy bone
 formation of red blood cells

Skeletal System
 Layers
of Bone
Yellow
marrow
Located inside hollow portion
 Fat storage cells
 Energy storage

Skeletal System
 Types
 Long
of Bone
Bones
Longest
 Provide support and
movement
 Levers

 Example
-- legs, ribs,
pelvic bones
Skeletal System
 Types
 Short
of Bone
Bones
Smaller than long
 Joints
 Comfort and mobility

 Example
hands
-- feet and
Skeletal System
 Types
of Bone
 Irregular
Bones
Have an irregular
shape
 Support and protect

 Example
-vertebrae
Skeletal System
 Types
 Flat
of Bone
Bones
Thin and flat
 Protect organs

 Example
-- skull
Skeletal System
 Joints
 Where
different bones meet
 Ligaments
 Connect
bones together; tough tissue
Skeletal System
 Joints
Classified
by the way they move.
Hinge Joint
Ball and Socket
Gliding
Muscle System
 Function
 To
provide movement for the
proper functioning of the
organs.

Meat production
 Muscles
are processed into
meat
 30-40% of the animal’s body
is muscle.
Muscle System
 Skeletal
Muscle
Movement
for the
bones
Voluntary movement
Composed of long,
striated bundles that
contract and relax
Muscle System
 Skeletal
Red
Muscle
Muscle
Contain many mitochondria;
 Lots of blood; contract for long periods of time

Muscle System
 Skeletal
White
Muscle
Muscle
 Fewer
mitochondria
 Contract faster
 Fatigue faster.
Muscle System

Smooth Muscle
 Movement
Controls movements of the
internal organs
 Involuntary.

 Examples-- Digestive tract,
urinary tract
Muscle System
Muscle System

Cardiac Muscle
Movement
 Muscles
that control the heart
 Involuntary
Circulatory System
 Function
Transports
 Water
 Oxygen
 Wastes
Regulates
temperature
Removes disease
Circulatory System
 Heart
 Center
of the circulatory
system
 Large muscle
 Pumps
continuously
Circulatory System
 Blood
Vessels
Arteries
 Vessels
that take blood
away from the heart
Veins
 Vessels that return blood
to the heart
Circulatory System
 Capillaries
Connect
arteries and veins
Deliver nutrients to the cells
Take away waste
Circulatory System
 Red
Blood cells
Give
blood color
Carry oxygen
 White
Blood cells
Destroy
Pus
disease
Circulatory System

Four Chambers
 Right Atrium

Receives blood into heart from
body, from veins
 Right

Pumps blood out to the lungs
 Left

Atrium
Receives blood into heart from
lungs
 Left

Ventricle
Ventricle
Pumps blood out into body via
arteries
Lungs
Veins
Right Atrium
Right Ventricle
Left Atrium
Left
Ventricle
Arteries
Respiratory System
 Function:
 Takes
oxygen from the air
 Places it in the bloodstream
 Removes carbon dioxide
Respiratory System
 Structures
Nostrils
 Large
Nasal
amounts of air
Chamber
Mouth
 Brings
in air
Respiratory System
 Structures
Pharynx
 Passageway
for
Food
Water
Air
Controlled
by epiglottis
Respiratory System
 Larynx
Voice
box (Adam’s apple)
Prevents material from
entering lungs.
 Trachea
Large
tube
Made of rigid cartilaginous
rings
Respiratory System
 Bronchi
Branch
out
further
 Lungs
Gas
exchange
Respiratory System

Alveoli
 Surrounded
by
blood vessels
 Carbon dioxide is
removed from blood
 Oxygen is absorbed
into blood
Respiratory System
 Diaphragm
 Large
muscle under the lungs
 When contracted, rib cage expands
and air comes in
 When the diaphragm relaxes, air is
forced out
Nervous System

Function:
 Central
system
Motor Control
 Sensation

Nervous System

Nerves
 Long
fiber like
structures

Motor Neurons
 Controls
impulses
sent from the brain
 To other parts of
the body
Nervous System

Sensory Neurons
 Send
impulses from
the body to the brain.

Spinal Cord
 All
nerves are
connected
 Runs through the
backbone (vertebra)
Nervous System

Brain
 Center
of the
nervous system
 Divided into 3
sections
Nervous System
 Brain
1.
Cerebrum
 Largest
 Controls
process
 Ouch!
thought
Nervous System
 Brain
2.
Cerebellum
 Coordinator
center for the
cerebrum
 Many
movements are
required to walk,
eat, etc…
Nervous System
 Brain
3.
Medulla oblongata
 Involuntary
activities
 Heart
beat
 Digestion
 Breathing
 Body
Temp.
 Feeling – Fear or Thirst
Nervous System

Brain Stem
 Connects
the spinal cord to the cerebrum.
Endocrine System

Function:
 Composed

of glands that secrete hormones.
Hormones:
 Chemical
agent that causes an effect in the
body.
 Hormones control vital function of the body.
Growth
 Reproduction

Endocrine System

Pituitary Gland:
 Located
at the base of the brain
 Master gland

Functions
 Growth
of bone
 Maternal Behavior
 Reproduction cells
Endocrine System

Hypothalamus
 Links
the Endocrine with the nervous system.
 Location

Under the lower front part of the brain
 Secretes
hormones for:
Hunger
 Sleep
 Body Temp

Endocrine System

Adrenal Gland
 Located
by Kidney
 Adrenalin – Times of stress

Thyroid Gland
 Front
of wind pipe
 Controls rate of digestion
 Storage of calcium
Endocrine System
 Pancreas
 Below
the stomach
 Produces Insulin and glucagons
 Regulates
stream
the amount of glucose in the blood
Excretory System
 Function:
Rid
the body of wastes
Kidney
 Remove
urea and nitrogen
 Filtrates liquids ingested.
Wastes
are flushes out the urinary tract.
Digestive System
 Function:
Animal
takes in food
Digested in to a form that the body can
use.
 Basic
etc…
elements – Oxygen, Iron, Potassium,
Digestive System

Monogastric
 Simple
stomach
 One compartment
Pigs
 Horse
 Dog
 Cat

Digestive System
 Modified
Monogastric System(PseudoRuminant)
Horse
 Rabbit


Uses cecum to digest roughage
Digestive System
 Ruminant
Cows
Goats
Sheep
Deer
Elk
System
Digestive System
 Monogastric
Mouth
 Grind
down food
Esophagus
 Push
food to
stomach
 Muscles move
food down
Digestive System
 Monogastric
Stomach
 Muscles
 Contacts
and relaxes
 Food
pressed together
 Digestive juices secreted by the stomach
lining.
 Hydrochloric
Acid
Digestive System
 Monogastric
Stomach
 Food
is dissolved from movement and acid.
Digestive System
 Monogastric
Small
Intestine
 Duodenum
Secreted from
pancreas
 Breaks down proteins,
starch and fats.
 Juices still secreted to
break down food.

Digestive System
 Monogastric
Small
Intestine
 Jejunum
 Nutrients
absorbed into the body
 From intestine to blood stream.
 Villi
– Semi-Permeable membrane
 Particles
pass through.
Digestive System
 Monogastric
Large
Intestine
 Cecum
 Not
used in
most
monogastrics
Digestive System
 Monogastric
Large
Intestine
 Colon
 Storage
of
waste
 Water is
removed
Digestive System
 Monogastric
Rectum
 Muscle
body.
that passes waste out of the
Digestive System
 Ruminant
System
These
eat large quantities of fibrous
material.
 Hay
 Alfalfa
 Etc…
Roughage
– Fibrous Feed
Digestive System
 Ruminant
Multi
compartment (4 main)
 Breaks
They
System
down the polysaccharides
chew their (CUD)
Digestive System
 Ruminant
System
Mouth
 Food
is ground
down by teeth
 Also used to
brake down the
cud.
Digestive System
 Ruminant
System
Teeth
– Lower front teeth
 Dental pad – Upper part of mouth
 Molars
 Incisors
Used
to tear forages from ground
Digestive System
 Ruminant
Must
System
produce large amounts of saliva
Used to feed microorganisms in the
rumen
Digestive System
 Ruminant
System
Esophagus
 Transport
food to
digestive tract
 Transport CUD to
mouth.
Digestive System
 Ruminant
System
Reticulum
 Hardware
 Due
stomach
to large mouth they collect hardware
 Wire form fence
 Rocks
 Etc…
Digestive System
 Ruminant
System
Reticulum
 Secretes
mucus
 Honeycomb shaped
 Traps hardware from
traveling to the rest
of the digestive
system.
Digestive System
 Ruminant
System
Reticulum
 Regurgitation
 Packs
feed into and eggs shaped ball to be
re-chewed. (CUD)
Digestive System
 Ruminant
System
Rumen
 Largest
compartment
 Food is soaked, mixed.
 Microorganisms ferment
the feed.
 Carbohydrates are
absorbed by the papillae.
 Small
fingerlike projections
that aid in absorption
Digestive System

Ruminant System
 Omasum
Size of a quarter to enter.
 Round – Soccer Ball
 Many Folds – Like a round book
 Grinds the food as it passes
through.

Digestive System

Ruminant System
 Abomasum
True stomach
 Functions the same as the
monogastric

 Intestines
are the same as
monogastric.
Animal
Reproduction
Biology Agriculture
Reproductive System

Ovaries
 Female
reproductive gland in which eggs are
formed and hormones are produced.

Testes
 Male
reproductive gland that produces sperm
and testosterone.
Reproductive System

Female Reproductive Cell
 EGG

(OVULE)
Male Reproductive Cell
 SPERM
 Semen
- the fluid that carries sperm and
nourishes
Reproductive System
• Production of sperm is called
SPERMATOGENESIS
• Production of eggs is called OOGENESIS
Reproductive System

Zygote
 Cell
formed by the union of egg and sperm
at fertilization.

Embryo
 Organism

Pregnancy
 carrying

in early stages of development.
a fetus
Fertilization
 the
union of the egg and sperm nuclei
Reproductive System

Conception
 occurrence

Ovulation
 release

of fertilization
of an ovule from the female.
Gestation
 the
time from fertilization or conception of a
female until she gives birth
Reproductive System

Vulva -opening of reproductive tract
Reproductive System

Vagina - channel for birth and urinary tract
Reproductive System

Cervix - divides vagina and uterus
Reproductive System

Uterus - provides nourishment for fetus
Reproductive System

Horns of Uterus - where fetus grows
Reproductive System
• Fallopian Tube - where fertilization occurs
Reproductive System

Ovaries - produces eggs and hormones
Reproductive System

Testes - produce sperm and testosterone
Reproductive System

Epididymis - collects and stores sperm
Reproductive System

Vas deferens - transports sperm
Reproductive System

Penis - places sperm in female
Reproductive System

Scrotum - protects testes, maintains temp
Reproductive System

Sheath - opening of reproductive tract
Animal Reproduction

Ovaries – produces eggs
and hormones
Animal Reproduction

The ovaries are
stimulated by a hormone
called the follicle
stimulating hormones
(FSH) and produce a
FOLLICLE where the egg
(ovum) grows and
matures
Animal Reproduction

When the egg matures
the follicle ruptures and
releases the egg OVULATION
Animal Reproduction
Mating Process

Around the time of ovulation estrogen
causes estrus or heat
 The
time that the female will allow the male to
mate with her

Males seek out females that are in estrus
Mating Process

During mating millions of sperm are
deposited in the female vagina.

Sperm moves by using their tails in a
whiplike action – motile
Mating Process

Sperm travels from the vagina through the
cervix and uterus and into the fallopian
tubes

Sperm and egg unit in the fallopian tube
Reproductive Technologies
 Reproductive
 Any
Technologies
method of reproduction that is different
from natural methods
Reproductive Technologies

Embryo Transfer:
 The
transfer of fertilized egg(s) from a donor
female to one or more recipient females
Reproductive Technologies
 Embryo
Transfer
Reproductive Technologies
 Embryo
Transfer
Reproductive Technologies
 Super
Ovulation:
 Giving
animals a hormone that causes
them to produce more then one egg.
Reproductive Technologies
 Artificial
 Placing
Insemination
sperm into the female
reproductive tract by means other than
natural mating.
Reproductive Problems

Sterility:
 Inability

of an animal to reproduce
Freemartin:
 In
twins, when a female is exposed to male
testosterone before birth.
 Causes problems with the development of
female reproductive organs
Reproductive Practices

Purebreeding
 Breeding
two pure breed animals together
 Usually papered to prove genetics

Crossbreeding
 One
breed is breed to another
 Ex. Angus x Herford = Black Baldy
Reproductive Practices

Grading-up
 Taking
grade cows and breeding to purebreds