• Central Concepts: There is a relationship between the organization of cells into tissues and the organization of tissues into organs. The structures and functions of organs determine their relationships within body systems of an organism. Homeostasis allows the body to perform its normal functions.
• 4.1 Explain generally how the digestive system (mouth, pharynx, esophagus, stomach, small and large intestines, rectum) converts macromolecules from food into smaller molecules that can be used by cells for energy and for repair and growth.
Digestive System• Function:
– Break down food into usable materials for cells in the body to use
• How does it work:– Uses enzymes throughout each part to break down
polymers into monomers• Example: mouth has amylase to break down carbs
– Absorbs monomers and nutrients in the small intestine and transports them through the body in the blood (for energy, growth, and repair)
– Absorbs water in the large intestine and all else is removed through the anus
• Central Concepts: There is a relationship between the organization of cells into tissues and the organization of tissues into organs. The structures and functions of organs determine their relationships within body systems of an organism. Homeostasis allows the body to perform its normal functions.
• 4.2 Explain how the circulatory system (heart, arteries, veins, capillaries, red blood cells) transports nutrients and oxygen to cells and removes cell wastes. Describe how the kidneys and the liver are closely associated with the circulatory system as they perform the excretory function of removing waste from the blood. Recognize that kidneys remove nitrogenous wastes, and the liver removes many toxic compounds from blood.
Circulatory System• Function:
– Transports O2 and nutrients to cells and removes CO2 and waste from cells
• How does it work:– Heart pumps the blood and blood vessels carry the
material in blood– Oxygen is carried on red blood cells
• Hemoglobin, which has iron, holds onto the O2
– Nutrients come from the digestive system– Wastes are transported to the kidneys and liver for
breakdown and removal
Circulatory Diagram
• Blood Vessels– Arteries
• Brings blood away from the heart
– Veins• Brings blood to the
heart
– Capillaries• Brings blood to and
from organs• Smallest vessels
To liver
kidneys
To lungs
veinartery
heart
Kidneys and Liver
• Liver: – Breaks down toxic material so it is no longer
harmful and sends them to the kidneys through the blood
• Kidneys: – Filters out material that needs to be removed from
the body • Example: nitrogenous waste (waste that has Nitrogen)
– Creates urine
Respiratory System
Diagram• Gas exchange
occurs in the alveoli– Capillaries
surround the alveoli
– O2 enters and CO2 exits
• Central Concepts: There is a relationship between the organization of cells into tissues and the organization of tissues into organs. The structures and functions of organs determine their relationships within body systems of an organism. Homeostasis allows the body to perform its normal functions.
• 4.3 Explain how the respiratory system (nose, pharynx, larynx, trachea, lungs, alveoli) provides exchange of oxygen and carbon dioxide.
Respiratory System• Function:
– Bring O2 to blood vessels– Take CO2 from blood vessels– Cleans the air (bacteria, dust, pollen, virus)
• How does it work:– O2 is collected in the lungs when you inhale– Gas exchange occurs in the smaller parts (alveoli)
when CO2 exits the blood and O2 enters– CO2 leaves the lungs when you exhale– Cilia on cells and mucous trap harmful material
• Central Concepts: There is a relationship between the organization of cells into tissues and the organization of tissues into organs. The structures and functions of organs determine their relationships within body systems of an organism. Homeostasis allows the body to perform its normal functions.
• 4.4 Explain how the nervous system (brain, spinal cord, sensory neurons, motor neurons) mediates communication among different parts of the body and mediates the body’s interactions with the environment. Identify the basic unit of the nervous system, the neuron, and explain generally how it works.
Nervous System
• Function:– Receive and send messages throughout the body– Includes messages from inside and outside the
body– Regulates the body to keep homeostasis
• How does it work– Uses individual cells called neurons to send
electrochemical signals throughout the body• Uses electrical impulses and chemicals (called
neurotransmitters) to communicate
Parts of the Nervous System• Brain
– Central organ that collects signals and sends messages
• Spinal Cord– Links brain to the rest of the body
• Neurons– Sensory neuron
• Takes in information from the body and sends it to the brain
– Motor Neuron• Brings signals from the brain to the body
• Central Concepts: There is a relationship between the organization of cells into tissues and the organization of tissues into organs. The structures and functions of organs determine their relationships within body systems of an organism. Homeostasis allows the body to perform its normal functions.
• 4.5 Explain how the muscular/skeletal system (skeletal, smooth and cardiac muscles, bones, cartilage, ligaments, tendons) works with other systems to support the body and allow for movement. Recognize that bones produce blood cells.
Skeletal System• Functions
– Maintain Posture– Produce Movement (with the muscular system)– Make blood cells
• How does it work– Bones and cartilage create structure– Bone marrow (inside bones) make red and white
blood cells– Ligaments and tendons hold bones to muscles to
help with movement
Muscular System
• Function – Produce movement
• How does it work– Cardiac muscle moves the heart– Skeletal muscle moves the bones and the body– Smooth muscle moves material in the body
• Example: moving food down the esophagus (peristalsis)• Example: moving urine to the urinary bladder• Example: moving blood up the veins• Example: contractions during labor
• Central Concepts: There is a relationship between the organization of cells into tissues and the organization of tissues into organs. The structures and functions of organs determine their relationships within body systems of an organism. Homeostasis allows the body to perform its normal functions.
• 4.6 Recognize that the sexual reproductive system allows organisms to produce offspring that receive half of their genetic information from their mother and half from their father, and that sexually produced offspring resemble, but are not identical to, either of their parents.
Reproductive System• Function
– Produce gametes (sperm and eggs)
• How does it work– Cells in the testis and ovaries use meiosis to create
gametes• Each cell has half the number of chromosomes (haploid)• Fertilization fuses an egg and sperm together to make a
zygote with 2 sets of chromosomes (diploid)• Offspring are genetically unique compared to each parent
• Central Concepts: There is a relationship between the organization of cells into tissues and the organization of tissues into organs. The structures and functions of organs determine their relationships within body systems of an organism. Homeostasis allows the body to perform its normal functions.
• 4.7 Recognize that communication among cells is required for coordination of body functions. The nerves communicate with electrochemical signals, hormones circulate through the blood, and some cells produce signals to communicate only with nearby cells.
Communication in the Body• Function
– Regulate the body (keep homeostasis)
• How does it work– Neurons use electrochemical signals to send signals– Hormones move through the blood to send signals to
organs for responses• Produced by endocrine cells in glands (example: thyroid,
adrenal)
– Cells nearby can communicate with each other• Called paracrine signals• Example: antibodies released from immune cells• Example: neurotransmitters from neurons
Communication in the Body
• Paracrine vs Endocrine
Paracrine signaling
Local regulatordiffuses throughextracellular fluid
Secretoryvesicle
Secretingcell
Target cell Electrical signalalong nerve celltriggers release ofneurotransmitter
Neurotransmitter diffuses across synapse
Endocrine cell Bloodvessel
Hormone travelsin bloodstreamto target cells
Synaptic signaling
Target cellis stimulated
Hormonal signaling
Target cell
Paracrine signaling
Local regulatordiffuses throughextracellular fluid
Secretoryvesicle
Secretingcell
Target cell
Local signaling
Electrical signalalong nerve celltriggers release ofneurotransmitter
Neurotransmitter diffuses across synapse
Endocrine cell Bloodvessel
Long-distance signaling
Hormone travelsin bloodstreamto target cells
Synaptic signaling
Target cellis stimulated
Hormonal signaling
Target cell
• Central Concepts: There is a relationship between the organization of cells into tissues and the organization of tissues into organs. The structures and functions of organs determine their relationships within body systems of an organism. Homeostasis allows the body to perform its normal functions.
• 4.8 Recognize that the body’s systems interact to maintain homeostasis. Describe the basic function of a physiological feedback loop.
Homeostasis
• Function– Regulate the activities in the body– Keep the body at stable conditions– Respond to changes
• How does it work– Uses communication systems to send signals and
balance the body• Called feed back loops
– Organs systems work together to keep homeostasis