Animal Systems Flashcards
What is the function of the circulatory system?
To transport nutrients and O2 from intestines and lungs to all cells, wastes and CO2 from cells to areas of disposal and to lungs to be exhaled
What are the four components of blood?
Red blood cells, white blood cells, platelets, plasma
Red Blood Cells
Makes up half blood’s volume, contains hemoglobin allowing for transport of O2
What is the circulatory system made up of?
Blood, blood vessels, heart
White Blood Cells
Less than 1% of blood, important in infection fighting
Platelets
Less than 1% of blood, tiny cells that help in blood clotting
Plasma
More than half of blood’s volume; protein-rich, clear, yellowish liquid that carries blood cells along
The Heart
A muscular pump made of cardiac muscle cells
What is Heart Rate?
The frequency of the heart beat
What are the three main blood vessels?
Arteries, Veins, and Capillaries
Arteries
Carry blood away from the heart and towards the tissues, thick muscular walls allow blood to be carried under high blood pressure.
Veins
Vessels carry blood toward the heart and from the tissues, walls are thinner since blood is under much less pressure
Capillaries
Arteries and veins linked together by capillaries, very small vessels (microscopic). Very thin walls allow for diffusion of O2,nutrients, CO2 and wastes.
What is the function of the digestive system?
The digestive system takes care of eating and processing food, and excreting wastes.
What are the parts of the digestive system?
In the digestive tract - mouth, esophagus, stomach, small and large intestine, anus. Accessory organs - liver, pancreas, gall bladder
What is the Digestive Tract?
A long tube with an opening at the end, lined with epithelial tissue which consists of goblet cells that can produce mucus. Also lined with muscle tissue to push the food along.
Mouth
Breaks down food Mechanically (teeth, tongue) and Chemically (enzymes [saliva] break larger molecules into smaller ones)
Esophagus
Muscular tube connecting mouth to stomach with layers of involuntary (smooth) muscle which push the food along.
Stomach
Muscular pouch designed to hold food and churn it with various digestive juices which are secreted from cells lining the stomach along with acids.
Small Intestine
Tube, about 6m long, uses smooth muscles to push food along, secretes enzymes to digest food, nutrients are passed across cell membrane into blood vessels that once in blood stream are delivered to all cells.
Large Intestine
Shorter portion of the intestine (about 1.5m). Water and fluids are absorbed from the waste and are eventually released from the anus
Accessory Organs
Liver, pancreas and gall bladder contribute to the digestion of food by adding digestive enzymes and fluids to food along the way.
Bile
Produced by the liver, it helps to break down fats.
What is the function of the Respiratory System?
It provides the body with O2 and rids the body of waste CO2, which must be exchanged to allow for cell respiration to occur in all our cells.
Respiratory Tract
Lined with epithelial cells, mucus and cilia help to moisten and filter the air to prevent dirt, dust and particles from entering the lungs.
What are the parts of the Respiratory Tract?
Trachea, Bronchi, Aveoli
Trachea
Air leaves the nose or mouth and enters the windpipe or trachea. It’s supported by rings of cartilage which keep the trachea open.
Bronchi
The trachea branches into the right and left bronchus and are also supported by cartilage and branch further into many tinier tubes called bronchioles.
Aveoli
Microscopic air sac at the end of the tiniest tubes extending from each bronchus, where O2 and CO2 are exchanged with the blood, each alveolus is surrounded by its own capillary. The transfer of gases occurs by diffusion.
Breathing
Inhalation occurs as rib muscles move out and the diaphragm moves down. Breathing is involuntary and is controlled by a part of the brain that detects the levels of CO2 in the blood.
What is the Diaphragm?
Thin sheet of muscle below ribs.
What are some diseases that can occur in the respiratory system?
Tuberculosis, Cancer, Asthma
What is the function of the Musculoskeletal System?
To support and protect the body and its vital organs and to allow movement.
What is the skeleton made up of?
The skeleton is made up of various types of connective tissue such as bones, ligaments, tendons and cartilage.
Bone
Hard and dense, consists of minerals (Ca and P) and collagen fibres. Canals inside the bone contain nerves and blood vessels. Only a small % of bone tissue is actually living.
Marrow
Found in bones, produces red and white blood cells and stem cells.
Ligaments
Tough, elastic tissues that connect bones (bone to bone) together at joints and are mostly made of long collagen fibres.
Tendons
Similar to ligament but less elastic, they connect bones to muscles.
Cartilage
Dense tissue made up of special cells -in a matrix of collagen fibres- to provide flexible, low-friction support for bones and prevent damage. (Can be found in ears, nose, between vertebrae and in joints)
Muscles
Attached to the skeleton to help it move, designed to contract and relax, consist of bundles of long mus. fibres containing specialized proteins. (When nerve cells send a signal, it causes the muscles to contract)
What are the three types of muscle?
Skeletal (vol.), Smooth (invol.), Cardiac
Skeletal Muscle
Attached to bones by tendons and allow voluntary movement of body parts
Smooth Muscle
Line internal organs (digestive tract) and blood vessels
Cardiac Muscle
Specialized cells making up the heart which contract and relax rhythmically.
How do muscles make bones move?
Nervous system sends a signal and the muscles pull on the bones it’s connected to.
Osteoporosis
Condition due to loss of bone tissue, making bones brittle and weak. More common in older women, can be diagnosed using bone density test. Foods high in vitamin D and Ca and exercise can help prevent
Vertebrates
Have musculoskeletal systems similar to ours
Invertebrates
No internal skeleton
Insects and Arthropods
Hard outer exoskeleton and internal muscles to help fly, walk and eat.
What is the function of the Nervous System?
It is responsible for the control of the body and communication among its parts, connecting brain to all other body parts through nerves. (Consisting of neurons)
What are the two main parts of the nervous system?
The central nervous system and peripheral nervous system
Central Nervous System
Consists of the brain and spinal cord. Brain is protected by cerebrospinal fluid and the skull. Spinal cord protected by cerebrospinal fluid and the vertebrae.
Brain
Receives info from all secondary organs (smell,taste,touch,hearing,vision) and forms a response if necessary. Also contains centres for thought and memory, allows us to interpret info and make decisions.
Spinal Cord
Extends from brain and down the back. Transfers info to and from brain. Is also responsible for reflex actions (not requiring conscious thought)
Peripheral Nervous System
Consists of all nerves extending beyond brain and spinal cord. Relays info about internal and external environments (to and from brain to other organs)
What are the three types of nerves in the PNS?
Nerves that control voluntary muscles, nerves that carry info to and from specialized neurons called sensory receptors, and nerves that regulate involuntary functions.
Where do you find sensory receptors?
Eyes, ears, taste buds, touch receptors
How many neurons are there in the brain?
100 billion
