Integumentary System

The major functions are to act as a barrier to protect the body from the outside world, retain body fluids, protect against disease, eliminate waste products, and regulate body temperature.

Stratum Corneum- Lots of keratin in this layer, and all the cells are dead. This functions as a barrier.

Stratum Lucidum- found in palms and soles to make thick skin

Stratum Granulosum- Cells lose their nuclei

Stratum Spinosum- Cells become connected and start to produce lamellar bodies

Stratum Basale- Living cells, replace cells that slough off above

Inter-Related Body Systems

The Muscular System- Covers all of the external muscles and is attached by connective tissue.

The Immune System- The first layer of defense against external threats.

The Nervous System- The epidermis contains a lot of sensory nerves, and provides the brain with a lot of information about the environment.

Reproductive System

The major function of the reproductive system is to have offspring with healthy genes.

Females:
Ovaries- small, oval-shaped glands that are located on either side of the uterus. The ovaries produce eggs and the hormones estrogen and progesterone.
Fallopian Tubes- tubes that are attached to the upper part of the uterus and serve as tunnels for the eggs to travel from the ovaries to the uterus.
Uterus-a muscular organ found in the female reproductive system that is responsible for the development of the embryo and fetus during pregnancy.
Cervix- allows flow of menstrual blood from the uterus into the vagina and directs sperm into the uterus during intercourse and it’s also the birth canal that a baby travels through as it’s being born.
Vagina- to serve as the passageway from the cervix to the outside of the body, and to serve as the birth canal for the fetus during childbirth and delivery.

Males:
Prostate- walnut-sized exocrine gland that borders the inferior end of the urinary bladder and surrounds the urethra. The prostate produces a large portion of the fluid that makes up semen.
Urethra- pathway for both urine and semen to leave the body
Penis- used for urination and reproduction.
Testicle- produces sperm and testosterone.
Vas Deferens- transport sperm from the epididymis to the ejaculatory ducts in anticipation of ejaculation.
Seminal Vesicles-  tubular glands posteroinferior to the urinary bladder of some male mammals.

Female Hormonal Cycle

Estrogen rises for about 2 weeks from the end of the period, begins to drop off, and then rises again for about a week before the period starts. Testosterone rises after a little under 2 weeks in and peaks at the same time as the estrogen peaks. Progesterone starts to rise about 2 weeks into the cycle, peaks at about 3 weeks and then drops.

Inter-Related Body Systems

The Muscular System- The hormones excreted by this system can affect muscle growth

The Nervous System- Hormones and pheromones can affect the way people think, and can give people unexplainable urges.

The Circulatory System- Hormones travel through the circulatory system

Immune System

The immune system is a system of biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, known as pathogens, from viruses to parasitic worms, and distinguish them from the organism’s own healthy tissue.

Thymus- produces hormones that regulate T-cell maturation and serves as the incubator against infections.

White Blood Cells- defends the body against many bacterial pathogens that cause diseases.

Antibodies- send signals to other parts of the immune system to attack and get rid of substances that cause diseases.

Spleen- removes dead red blood cells and also stores or produces lymphocytes.

Lymph Nodes- produces lymphocytes which help protect the body against microorganisms and harmful foreign particles.

Vaccines

Vaccines work by exposing the body to antigens of a similar type to the targeted illness. The body has an immune reaction to the antigens and builds some resistance to the actual disease. The body releases antibodies, T-cells, and B-cells which all help kill the virus. The body then stores a memory of these cells if it ever encounters the same disease again. If the host is infected with the actual disease, the body responds faster and more efficiently to kill the disease.

Inter-Related Body Systems

The Digestive System- Ingestion of outside materials can be risky, the immune system minimizes that risk.

The Circulatory System- the circulatory system can help circulate the cells of the immune system to help kill the disease.

The Integumentary System- The first line of defense against disease, if the disease cant get in the body, there’s no problem.

Endocrine System

The endocrine system is the collection of glands, each of which secretes different types of hormones that regulate metabolism, growth and development, tissue function, sexual function, reproduction, sleep and mood, among other things.

Hypothalamus- controls mood, thirst, hunger, and temperature.

Pituitary Gland- stimulates growth and cell reproduction, controls water balance, and causes an increase or decrease in the absorption of water into the blood by the kidneys.

Thymus- produces hormones that regulate T-cell maturation and serves as the incubator against infections.

Thyroid- plays an essential role in metabolism, growth, and maturation of the human body by releasing certain hormones into the blood.

Parathyroid- four tiny glands that help control the body’s calcium levels.

Adrenal glands- secrete hormones such as estrogen or testosterone that are essential to our health.

Pancreas- breaks down protein, carbohydrates and fats into fuel for the cells of the body.

Ovaries- they and release eggs into the female reproductive tract at the mid-point of each menstrual cycle and they also produce the female hormones estrogen and progesterone.

Testicles- to produce sperm and androgen which is the primary testosterone.

 

Inter-Related Body Systems

The Circulatory System- Helps circulate the hormones to get to where they need to be to be effective.

The Immune System- Stimulates the production of cells that can fight off infection.

The Skeletal System- Hormones help control calcium levels

Digestive System

The primary function of the digestive system is to break down the food we eat into smaller parts so the small and large intestine can absorb the nutrients and use them in the body.

Mouth- ingestion, such as food and water, and breaks down the food.

Esophagus- to carry food, liquids, and saliva from the mouth to the stomach.

Stomach- to break down food and extract the necessary nutrients to the body.

Small Intestine- to chemically digest food and absorb nutrients into the blood.

Large Intestine- to absorb water from the remaining indigestible food matter, and then to pass unwanted waste material from the body.

Pancreas- breaks down protein, carbohydrates, and fats into fuel for the cells of the body.

Gallbladder- used to store bile.

Liver- Makes bile, which breaks down lipids, and collect and destroys toxin in the body.

 

Food Path

• The food starts in the mouth, and is chewed. Starches are broken down by salivary amylase.
• The food moves to the esophagus as a bolus
• It moves to the stomach and is broken down by Hydrochloric acid, pepsin breaks down proteins
• Moves into the small intestine where nutrients are absorbed. Bile is added to break down lipids. Trypsin and Lipase from the pancreas break down amino acids and fatty acids respectively.
• Moves into the large intestine, where any remaining nutrients are absorbed, and the water is removed, leaving only waste.
• Waste is excreted

Inter-Related Body Systems

The Muscular System- Muscles cause peristalsis, which moves food through. Nutrients are provided to the muscles from the digestive system.

The Cardiovascular System- Capillaries help remove nutrients from the intestines through absorption.

The Integumentary System- If the digestive system is absorbing too much fat, it is stored under the skin.

 

Excretory System

The excretory system gathers and excretes waste, removing the negative byproducts of the body. 

The Kidneys- Filters the blood and removes waste, and regulates blood’s volume, pressure, pH, and ionic composition. 

Urinary Bladder- Storage for urine that has been filtered by the kidneys, eventually pushes the urine down the urethra when it gets full.

Ureter- Tube in which urine moves from the kidneys to the bladder, shaped to prevent back flow of urine.

Urethra- Tube that leads from the bladder to outside the body, used to remove the urine from the body.

Nephrons

Blood is filtered through the bowman’s capsule (large proteins are left in the bloodstream). The fluid that remains in the nephron after filtration is called the filtrate. The filtrate enters the proximal convoluted tubule. Glucose, amino acids, and water are secreted (released into bloodstream). The filtrate then moves on to the Loop of Henle. On descent, water leaves the filtrate by osmosis and on ascent; sodium and chloride leave the filtrate by active transport. The loop of henle becomes less permeable as it goes ascends so less sodium and chloride leave the filtrate as the filtrate makes its way up the loop. The filtrate then moves on to the distal convoluted tubule where pH is regulated and sodium potassium, and calcium levels are controlled. The filtrate then moves into the Collecting Duct. The collecting duct is what connects the nephrons to the ureter.

Inter-Related Body Systems

The Cardiovascular System- The kidneys filter the blood and keep waste from interfering with the blood function.

The Skeletal System- Kidneys excrete a hormone to promote red blood cell production.

The Digestive System- Similar to the digestive system because they both remove waste and absorb nutrients.

Muscular System

The muscular system consists of skeletal, smooth, and cardiac muscles. The main function of the muscular system is to permit the movement of the body, circulate blood throughout the body, and move things through the internal organs.

Smooth muscle- Found inside of organs like the stomach, intestines, and blood vessels. It is the weakest muscle tissue, because it only has to make organs contract to move substances through the organ. Because smooth muscle is controlled by the unconscious part of the brain, it is known as involuntary muscle.

Cardiac Muscle- Found only in the heart, cardiac muscle is responsible for pumping blood throughout the body. Cardiac muscle tissue cannot be controlled consciously, so it is an involuntary muscle.

Skeletal Muscle- Found all over the body, everything that you can make move. Skeletal muscle is the only voluntary muscle tissue in the human body. Almost all skeletal muscles connect to two bones, but all connect to at least one.

Inter-Related Body Systems

The Digestive System- The digestive system is lined with smooth muscle that moves the food through peristalsis.

The Integumentary System- The skin has very small muscles in it that help with temperature control by raising the hairs on your skin.

The Skeletal System- The Muscles connect to the bones and move the bones together to voluntarily move.

Skeletal System

The human skeleton serves six major functions; support, movement, protection, production of blood cells, storage of ions and endocrine regulation.

Types of joints

Hinge Joint-  the slightly rounded end of one bone fits into the slightly hollow end of the other bone. This works like the hinge of a door, and allows for angular movement. The elbow is a hinge joint.

Pivot Joint-  the rounded end of one bone fits into a ring formed by another bone. This allows for rotational movement around one axis. The joint of the first and second vertebrae of the neck is a pivot joint.

Ball and Socket Joint- the “ball,” or rounded end of one bone fitting into a cup like socket of another bone. This allows for the greatest range of motion, as movement is possible in all directions. This kind of movement is called circumduction. The hip joint is a ball and socket joint.

Inter-Related Body Systems

The Cardiovascular System- The bones produce red blood cells in the marrow, which supplies the cardiovascular system.

The Respiratory System- The ribs provide protection for the lungs and other internal organs.

The Muscular System- The muscles attach via tendons to the bones, which allows the muscles to contract and move the body.

Nervous System

The nervous system is the network in a body that coordinates all of it’s movements and sends signals from one part of the body to another. There are two parts, the central nervous system (cns) and the peripheral nervous system (pns). The cns is made up of the brain, spinal cord and the retina. The pns is made up of the sensory neurons, ganglia and nerves that connect to other systems and to the central nervous system.

Parts of the brain

Cerebrum- The cerebrum is the largest portion of the brain, made up of the four lobes of the brain. It controls most of the brain functions including movement, sensory processes, learning and language.

Frontal Lobe- Associated with reasoning, planning, parts of speech, movement, emotions, and problem solving

Parietal Lobe- Associated with movement, orientation, recognition, perception of stimuli.

Occipital Lobe- Associated with visual processing.

Temporal Lobe- Associated with perception and recognition of auditory stimuli, memory, and speech.

Cerebellum- Controls body functions such as balance, posture, and coordination.

Limbic System- Contains the thalamus, hypothalamus, hippocampus and the amygdala. Helps relay emotion.

Thalamus- Helps control the attention span, sensing pain and monitors input that moves in and out of

the brain to keep track of the sensations the body is feeling.

Hypothalamus- Controls mood, thirst, hunger, and temperature.

Hippocampus- Helps with learning and memory, which means it converts temporary memories into permanent memories which can be stored in the brain.

Amygdala- Helps the body respond to emotions, memories, and fear.

Brain Stem- Contains the medulla, midbrain, and pons. Heartbeat, blood pressure and breathing originate here.

Medulla- Maintains vital body functions such as heart rate and breathing.

Midbrain- Helps regulate body movement, vision, and hearing.

Pons- Links to the cerebellum to help with posture and movement.

Spinal Cord- To send sensations to the brain from other parts of the body and giving back motor commands to the various parts of the body and is also responsible for most body reflexes.

Nerves- To transmit impulses from sensory neurons and send it to the brain.

Neurons- Receive nerve signals, integrate action potentials and transmit signals to different body organs such as muscle and glands.

Action Potential

An action potential is part of the process that occurs during the firing of a neuron. Part of the neural membrane opens to allow positively charged ions inside the cell and negatively charged ions out. This process rapidly changes charge of the nerve fiber to positive. When the charge reaches +40 mv, the impulse is propagated down the nerve fiber.

Inter-Related Body Systems

The Muscular System- The brain sends voluntary signals to the muscles to tell them to move when necessary.

The Integumentary System- The skin is lined with nerves and sensors and sends a lot of information about the environment to the brain.

The Digestive system- The brain sends constant signals to the digestive system to keep it moving involuntarily.

Respiratory System

The main function of the respiratory system is the inhalation of oxygen and the exhalation of carbon dioxide. This body system is the oxygen supply for the whole body.

Trachea- Tube between the Larynx and Pharynx and the lungs, allowing passage of air to the lungs

Lungs- Primary organ involved in gas exchange, sacks of air

Epiglottis- Elastic cartillage at the entrance to the larynx, blocks food from going in the trachea

Larynx- Contains the vocal chords required to talk

Diaphram- sheet of internal skeletal muscle along the bottom of the rib cage, helps the lungs contract

Alveoli- ends of the respiratory tree involved in gas exchange

Bronchi- passageway of air, no gas exchange

Bronchioles- passageway of air split from the bronchi, leads to the alveoli.

Breathing

When you inhale, this brings the fresh, oxygen rich air into the lungs. It travels down the trachea, splits into bronchi, splits again into bronchioles which lead to the alveoli where gas exchange actually occurs. The alveoli are lined with capillaries that pass the carbon dioxide that they are carrying into the alveoli and pick up and oxygen. At the end of the process, there is more carbon dioxide in the alveoli than oxygen, and the body exhales and inhales to repeat the process.

Inter-related Body Systems

The Cardiovascular System- Provides oxygen to the blood to be circulated through the body.

The Muscular System- Many muscles are needed to expand and contract the lungs to a point that it brings in enough new air.

The Nervous System- Breathing is regulated by the body as an essential process, and happens without thinking about it.