Human System Review-Bio 20-1 AP Flashcards
Nutrient
Anything a cell needs ( gas, food, water, minerals, vitamins)
Food
An organic chemical which can be broken down in respiration to get ATP
Dehydration Synthesis
Making a larger molecule by taking out water
Hydrolysis
Using water to spilt a larger molecule into smaller parts
Carbohydrates
Make up 1% of protoplasm
Produced by photosynthesis & mainly used up in respiration for ATP.
Converted into needed body chemicals & fatty acids & non-essential amino acids
Can be identified by the formula (Carbon: Hydrogen: Oxygen)
Classes of Organic Compounds
Carbon, hydrogen and oxygen
Classes of carbohydrates
Monosaccharides, Disaccharides and Polysaccharides
Monosaccharides
One sugar units
Basic units of carbohydrates
5-carbon ring structure
(Ex. glucose, frctuose, galactose)
Disaccharides
2 sugar units
Two monosaccharides joined together with loss of water (Dehydration synthesis)
Glucose + Glucose =
Maltose [malt sugar] + water
Glucose + Fructose =
Sucrose [table sugar] + water
Glucose + Galactose
Lactose [milk sugar] + water
Polysaccharides
Many sugar units (Ex. Glygcogen, starch, cellulose)
Cellulose
Insoluble solid found in plant cell walls and is called plant fibre
We don’t have enzymes to digest it
-Joined by bonding about 3000 glucose together
- Forms layers not coils
- Ex. Celery & grass
Starch
Storage form of carbs in plants
Formed by bonding about 1100 glucose together as a helix or coils Animals convert it into glucose
Amylose and amylopectin are two forms
Glycogen:
Type of Polysaccharide
Storage form of carbs in animals
- Formed by bonding 700 glucose together
- Stored in cells of the muscles, brain and liver cells
Benedict’s Solution
For reducing sugars (ex. all monosaccharides)
Turns blue colour to red/ brown
Lipids
C, H, O compounds
Oils, fats, waxes and steroids (non-polar)
Function:
- Used in the structure of membranes.
- The storage form of energy- stores 2.25 times more energy per gram than other biological molecules.
The structure of some food
Iodine
Starch (Polysaccharides)
Turns yellow/ red liquid to black/blue
Saturated Fats
Lots of hydrogen
Usually solid @ room temperature
Most animal fats
Only have C -C single bonds
Fats
Sometimes called triglycerides
Formed by dehydration synthesis with enzymes
Structure: 3 fatty acids & 1 glycerol
Unsaturated Fats
Usually liquid @ room temperates
Most are found in plants as oils
C = C double bonds or triple bonds
Sudan IV
A test of lipid
Turns pink to red in the presence of lipid
It is a carcinogenic
Cholesterol
Formed by the bonding of one glycerol to a complex 4 ring, carbon structure
Most common steroid and is converted to vitamin D and hormones like testorone or estrogen
Animal Fats
Solid
Carries cholesterol
Long saturated fatty acids
Waxes
Semi-solids that are made by the bonding of 3 fatty acids to a long chain of alcohol instead of glycerol
Plant Fats
Liquid
No cholesterol
Short unsaturated fatty acids
Unglazed Brown Paper
Becomes translucent (see-through) in the presence of lipids
Peptide Bonds
Amino acids are connected together by peptide bonds
Proteins
Makeup structures such as hormones, enzymes, membranes
Energy is NOT the main function
The most abundant organic molecule
Synthesized at the ribosome
Made up of amino acids and amino acids bonded together on strands that form protein
Polypeptide
A chain of amino acids
Types of Protein
Primary
Secondary
Tertiary
Quaternary
Primary
Amino acids are in a linear sequence
Secondary
Hydrogen bonds between amino acids made alpha helix and beta sheets
Tertiary
3-D, R groups interaction alters helix
Quaternary
Globular proteins (Ex. enzymes)
Examples of Protein
Adrenalin, Insulin, Collagen [skin], Keratin [hair], Actin & Myosin [Muscle]
Denaturation
A slight change to the structure by breaking hydrogen bonds
Can be REVERSED
Coagulation
Breaking of bonds by extreme heat, acid or base
Can NOT be reversed
(Ex. frying an egg, high fever, stomach acid, base)
Biuret’s Reagent
Tests for peptide bonds
NOT individual amino acids
If it turns BLUE- Negative (No protein), turns PINK [+] turns VIOLET [++], turns PURPLE [+++]
Nucleic Acids
DNA & RNA
Structure: Sugar + phosphate + nitrogenous base
Genetic material that directs cell’s activity
Ways to increase the rate of chemical reactions
Increasing the concentration of a reactant in solution
Increasing the surface area of a solid reactant,
Increasing the temperature of the reaction system
Is increasing the temperature good for your body?
No, it is not good for your body as it will denature proteins in the body.
Catalyst
Another way to SPEED UP the reaction rate
It’s a chemical that speeds up a chemical reaction but isn’t used up in the reaction.
Can be recovered unchanged when the reaction is finished
Functions by lowering the amount of energy needed to start a reaction
Enzyme
A protein molecule that acts as a catalyst to increase the rate of reactions.
Each enzyme has a very specific shape that allows it to attach to a specific substance molecule called the REACTANT
When the substrate binds to the active site, its bonds become less stable and thus more likely to be altered and to form new bonds
They are a quaternary proteins
Active Site
The spot where the substrate binds to the enzyme
Substrate/ reactant
Is the substance that could fit into the enzymes
Factors Affecting Enzyme Action
Temperature
pH
Inhibitors
Inhibitors
Molecules that attach to the enzyme and reduce its ability to bind to the substrate
Non-Competitive Inhibitors
Attach somewhere else on the enzyme (NOT on the active site)
Changes the shape of the enzyme, making so the substrate no longer fits properly.
Competitive Inhibitors
Attach to the enzyme in its active site
Compete with the substrate to occupy the active site space
In biological systems, this is often the end product of enzymatic reactions as a form of negative feedback.
Ingestion
The taking in of nutrients
Digestion
The breakdown of complex organic molecules into smaller parts by enzymes
Absorption
The transport of digested nutrients to the cells of the body
Egestion
The removal of food waste from the body
Salivary Amylase
An enzyme that breaks down complex carbs (starch) into simple carbs
Salivary Glands
Produces saliva & salivary amylase
Teeth
Important for physical digestion
Grinds food into smaller pieces
Esophagus
Food moves from the mouth to the stomach through the esophagus
Peristalsis
Rhythmic, wave-like contractions of muscles that move food along the gastrointestinal tract
Stomach
Site of food storage and initial protein digestion.
Involved in the physical & chemical digestion that mixes food with the gastric fluids
Enzyme Pepsin starts protein digestion in the stomach
Digestive fluids in the stomach include hydrochloric acid (HCl), pepsinogens and mucus.
Has an ACIDIC enviroment
Mucus
Protects the stomach from HCl & Pepsin
Small Intestine
Completes digestion of macromolecules & absorbs their component sub-units
Most chemical digestion & absorption takes place here
Secretes digestive enzymes and moves its content along by peristalsis
Pancreas
Delivers pancreatic fluids to the duodenum and used for digestion in the small intestine
Storage for bicarbonate ions that neutralize stomach acid in the small intestine
Enzymes: Trypsin, chymotrypsin, pancreatic amylase, lipase are all found in pancreatic fluids
Liver
Secretion of the bile salts
Continually makes bile and blood proteins
Removes the highly toxic nitrogen group from amino acids forming urea
Converts the toxic part of hemoglobin
Converts glucose to glycogen and vice versa to maintain a constant blood sugar level
Stores glycogen, vitamins A, B12 and D
Converts harmful compounds to LESS harmful products (Ex. alcohol)
Gallbladder
Stores bile
Large Intestine
Reabsorbs water and salt from undigested food in the colon
Houses bacteria like E-Coli which are essential to life
Uses waste materials to make vitamins
Digestion DOES NOT occur here
Shorter but thicker than the small intestine
Digestion & Absorption in the Small Intestine
Most chemical digestion in the small intestine occurs in the duodenum
Lipase
Produced by the pancreas
Breaks down fats to glycerol & fatty acids
Fats + H2O = glycerol + fatty acids
Trypsinogen
Produced by the pancreas
Once activated to TRYPSIN by an enzyme called ENTEROKINASE it converts long-chain peptides into short-chain peptides
Protein Digestion
Protein digestion starts in the stomach with the enzyme pepsin.
In the small intestine, proteins are further broken down by trypsin and chymotrypsin, enzymes secreted by the pancreas.
Trypsin and chymotrypsin break peptide bonds between specific amino acids, forming shorter peptide chains.
Additional enzymes continue breaking down these short peptides, separating single amino acids from the ends.
Finally, peptidases from the pancreas and small intestine split the remaining peptide chains into individual amino acids, completing digestion.
Summary:
Digestion Starts: Stomach
Digestion Ends: Small Intestine
Carbohydrates Digestion
Starch digestion starts in the mouth with salivary amylase.
In the stomach, starch isn’t digested because the acidic pH (around 2) inactivates salivary amylase, which works best at pH 7.
Digestion resumes in the small intestine, where the pH is about 8.
Pancreatic amylase breaks down starch into disaccharides, and other enzymes convert these into monosaccharides like glucose, galactose, and fructose.
Digestion Starts in the MOUTH & ends in the SMALL INTESTINE
Carbohydrates absorption
Monosaccharides are absorbed into the cells of the intestinal villi by active transport.
From the intestinal lining, they enter the bloodstream and are carried directly to the liver.
The liver converts monosaccharides like galactose and fructose into glucose.
Glucose is then released back into the bloodstream and transported to body cells for energy.
Any excess glucose is converted into glycogen by the liver and stored in the liver and muscles for later use. When needed, glycogen is converted back into glucose to fuel the cells.
Absorption Pathway:
Small intestine → Bloodstream → Liver → Bloodstream → Body cells
Protein Absorption
Amino acids are absorbed into the villi of the small intestine through active transport.
They then diffuse into blood capillaries and are transported to the liver via the bloodstream.
In the liver, amino acids undergo various reactions before being sent back into the bloodstream to be used by cells that need them.
Absorption Pathway:
Small Intestine (Villi) → Bloodstream → Liver → Bloodstream → Body Cells
Fat Absorption
Glycerol and fatty acids are absorbed into the cells of the villi in the small intestine by simple diffusion.
Inside these cells, they are reassembled into triglycerides and coated with proteins to make them soluble.
The coated triglycerides enter the lymph vessels in the villi and are transported to the chest region, where they join the bloodstream.
Once in the bloodstream, the protein coating is removed by lipase in the blood vessel lining.
Lipase then breaks down the triglycerides again, making fatty acids and glycerol available for use by the body.
Absorption: Small Intestine [Villi] —> Lymph Vessels —> Bloodstreams
Fat Digestion
When fats enter the duodenum (the first part of the small intestine), they trigger the release of bile from the liver and gallbladder.
Bile emulsifies large fat droplets into smaller ones, increasing their surface area. (This is a physical process, not chemical digestion.)
Lipase, an enzyme secreted by the pancreas into the duodenum, chemically breaks down fats into glycerol and fatty acids through hydrolysis.
Digestion Starts & Ends: Small Intestine
Blood Capillaries
Absorption through active transport of amino acids & monosaccharides
Absorbs glucose & amino acids
Nucleic Acid Digestion & Absorption
Nucleic acids (DNA and RNA) are broken down in the small intestine by enzymes called nucleases, producing nucleotides.
Nucleosidases further hydrolyze nucleotides into their individual components: nitrogenous bases, sugars, and phosphates.
These components are then absorbed into the bloodstream via active transport.
Lacteals
Absorption through passive transport of fatty acids & glycerols (Tiny lymphatic vessels)
Sphincter
Control the passage of food from one area to another by use of a circular band of muscles
- Cardiac Esophageal Sphincter:
Between the esophagus & stomach
Pyloric Sphincter:
Between stomach & small intestine
Ileocecal Sphincter:
Between the small intestine & large intestine
Rectal Sphincter
Below the rectum
Salivary Amylase
Secreted by the salivary glands
Starts the breakdown of polysaccharides to monosaccharides
Hydrochloric Acid (HCl)
Kills pathogens
Helps convert PEPSINOGEN to PEPSIN
Secreted by the stomach
Pepsinogen
When converted to pepsin by HCl it initiates the digestion of PROTEINS
Pancreatic amylase
Secreted by the pancreas and continues to breakdown of carbs into disaccharides
Starch + Water = maltose
Bicarbonate Ions
Secreted in the pancreas and neutralizes HCl from the stomach
The orgin of secretion is the PANCREAS
Erepsin
Secreted in the SMALL INTESTINE and the pancreas it completes the breakdown of proteins
Turns short-chain peptides –> Individual amino acids
Peptides + water = amino acids
Maltase
Disaccharides secreted by the small intestine
Breaks down disaccharides to monosaccharides
maltose + water = glucose
Bile
Produced by the liver and stored by the gallbladder till it is delivered to the small intestine
Bile emulsifiers fat
Circulatory Systems:
Transportation system for oxygen, nutrients, and cell waste to move throughout the body
Major Functions of Circulatory System
- Transports gases (From the respiratory system) nutrient molecules (From the digestive system) and waste materials (From the executory system)
- Regulate internal temperature & transport hormones
- Protect AGAINST blood loss from injury & AGAINST disease-causing microbes or toxic substances introduced in the body
Major Parts of the Circulatory System
- 3 Major components:
- Heart: Pushes blood throughout the body with its pumping action & generates blood flow
- Blood Vessels: Serves as PATHWAYS for blood to move
- Blood: CARRIES nutrients, oxygen, carbon dioxide, water, waste and other materials throughout the body
Cardiovascular Systmes
“Cardio” = Heart
“Vascular” = Vessels
The cardiovascular system is the heart & blood vessels
Pulmonary Pathway
Pumped by the RIGHT SIDE of the heart
Transports oxygen-poor blood to the LUNGS
When it gets oxygen from the lungs the oxygen-rich blood is returned through the Pulmonary Veins
Vena Cava –> Right Atrium –> Rigtht AV Valve –> Left Ventricle –> Semilunar Valve –> Pulmonary Artery –> Lungs
Systemic Pathway
Moves oxygen-rich blood from the left ventricle of the heart to the body tissues (Body Systems)
It is pumped by the LEFT side
Pulmonary Veins –> Left Atrium–> Left AV Valve –> Left Ventricles –> Semilunar Valve –> Aorta –> Body
Coronary Pathway
Provides blood to the heart
It is pumped by the LEFT side
Aorta –> Coronary Artery–> Cardiac Veins
Structures of Blood Vessels
Arteries, veins, capillaries
Arteries
- Carry oxygen-rich blood AWAY from the heart
-
Highly elastic walls allow the artery to expand as blood moves through during the contraction of the ventricles and snap back again during the relaxation of the ventricles
Keeps blood flowing in the right direction
Provides a pumping motion to help force blood through the blood vessels [You can feel this when you feel your pulse]- MEMORY TIP: Arteries —> Away (Both start with “A”)
Veins
- Carry Oxygen-poor blood towards the heart
- Thinner walls & larger inner circumference than arteries
- NOT elastic, CANNOT contract to help blood move to the heart, instead muscles help keep the blood flowing toward the heart
- Have one-way valves that prevent blood from flowing backwards
- Muscles RELAXED = Valves CLOSED
- Muscles CONTRACTED = Valves OPEN
Capillaries
- Where gases, nutrients and other materials are transferred to tissue cells and wastes, including gases, move into the blood
- Smallest blood vessels
- Spread throughout the body in a fine network
- The capillary wall is a single layer of cells with a tiny diameter making it so that the blood cells pass through a single file
Pulmonary Artery
Carries deoxygenated blood (Oxygen-poor) AWAY from the heart
INSTEAD of the oxygenated blood arteries usually carry
Pulmonary Vein
Carries OXYGENATED blood (Oxygen-rich blood) to the heart
INSTEAD of the deoxygenated blood veins usually carry.
Heart Beat
Is an electrical signal coming from the heart
SA Node [Pacemakers] –> Atria Contract –> AV Node –> Purkinje Fibres–> Ventricles Contract
Sinoatrial (SA) Node
- A bundle of specialized muscle located in the wall of the right atrium
- Stimulates muscle cells to contract & relax rhythmically
- Generates an electrical signal that spreads over the two arteries and makes them contract simultaneously
It STARTS the impulses stimulating the heartbeat
Atrioventricular (AV) Node
- As the atria contracts the signal reaches the AV node
- AV nodes transmit the electrical signal through a bundle of specialized fibre called the bundle of His
- Those fibres relay the signal through two bundle branches that dive into fast, conducting Purkinje fibres, which start almost simultaneous contraction of all cells of the right & left ventricles
Purkinje Fibre
A nerve fibre that branches and carries electrical impulses throughout the ventricles
Heart Sounds
- The sound the heart makes can be described as a “lubb-dubb” sound
- This sound is made by the closing of the different heart valves
Lubb Sound
- When the atria relax they fill with blood
- The atria the contract, which increases fluid pressure and forces the AV valves open
- This causes blood to flow from the atria to the ventricles
- Next, the ventricles contract and this pressure forces the AV valves shut which produces the lubb sounds and pushes blood through the semilunar valves and into the arteries
Dubb Sounds
- Next, the ventricles relax and their volume increases
- This causes the pressure in the ventricles to decrease and blood is drawn to this area of lower pressure
- Blood is prevented from re-entering the ventricles by the semilunar valves
- The closing of the semilunar valves creates the dubb sound
Cardiac Output
Amount of blood PUMPED by the heart each minute
Heart Rate
Number of heartbeat per minute
Stroke Volume
Amount of blood forced out of the heart with each heartbeat
Formula For Cardiac Output
Cardiac Output = Heart Rate X Stroke Volume
Blood Pressure
Pressure against the vessel wall of the arteries
Systolic Pressure
MAX pressure during the ventricular contraction
Diastolic Pressure
LOWEST pressure before the ventricles contract again
Heart Pressure
Things That Can Impact Blood Pressure
Diet, Age, Stress, Exercise, Health Conditions
Increasing Heart Rate
Increase Blood Pressure
Increasing the amount of blood
Increasing Blood Pressure
Widening the Blood Vessels (Vasodilation)
Decreasing Blood Pressure
Enlarging the Blood Vessels
Decreasing Blood Pressure
Increasing elasticity of arteries
Decreasing Blood Pressure
Increasing viscosity of the blood
Increasing Blood Pressure
Average Blood Pressure
Systolic/ Diastolic = 120/80
Impact Exercise Have On The Heart
- Strong hearts are able to pump more blood with each heartbeat (Greater Stroke Volume)
- Cardiovascular exercise will increase a person’s resting stroke volume
- Enlarge ventricular chambers
- Increase the distensibility of their ventricles
- Strengthen the ventricle walls so that the person is able to pump more blood with each beat
Thermoregulation
Maintenance of body temp within a range that enables cells to function efficiently
What happens when the temperature is low?
When it is cold the hypothalamus turns on the warming systems.
It then sends a signal to the skeletal muscles to contract. Shivering occurs to generate heat. Body hair becomes erect to conserve heat.
The skin blood vessels constrict (Vasoconstriction) and there is a decreased blood flow to the skin.
Reduced heat loss from skin and retains the heat in the core of the body and to the brain.
Hypothalamus
A part of your brain that is responsible for coordinating many nerve and hormone functions
It also turns on cooling and warming systems when needed.
Helps regulate body temp by sending nerve impulse
Vasodilation
When the blood vessels become bigger
Vasoconstriction
When the blood vessels become smaller
What happens when the temperature is high?
When it is hot the hypothalamus turns on cooling systems.
It then sends a signal to the sweat glands to initiate sweating.
The evaporation of sweat causes cooling.
At the same time, a nerve message is sent to the skin’s blood vessels causing them to dilate. Increasing blood flow to the skin and the blood loses heat from the skin.
RESULT: The body temperature decreases and the hypothalamus turns off cooling systems.
What is in Blood?
Plasma, Red Blood Cells, White Blood Cells, and Platelets
Plasma
The fluid portion of blood
Contains water, vitamins, dissolved gases, proteins, sugars, hormones, minerals and waste products
The fluid portion of the blood
Carry all the blood cells
Plays a role in transporting carbon dioxide
Form Portion
The solid portion of the blood
It contains RBC, WBC and platelets
These are all produced in the bone marrow that is found inside the bone
Red Blood Cells
Also called Erythocyted
~44% of all blood volume
Has NO nucleus making more space for Oxygen gas
Specialized in oxygen transport
Hemoglobin
Iron-containing respiratory pigment found in RBC
- Special properties that allow it to pick up oxygen
- Transports oxygen to the cells through diffusion
It is like a magnet that attracts oxygen which creates oxyhemoglobin
Anemia
A condition that occurs if there are too few RBCs or too little hemoglobin inside the RBC
Reduces the amount of oxygen that is flowing through the body
Symptoms: Feel tired, appear pale
2 Types: Iron-deficient anemia & Sickle Cell Anemia (More severe & genetic)
Iron-deficient Anemia
A type of anemia that develops if you do not have enough iron in your body. It is the most common type of anemia.
Sickle-Cell Anemia
Is a group of inherited disorders that affect hemoglobin
Normally, RBCs are disc-shaped and flexible so they can move easily through the blood vessels.
In sickle cell disease, RBCs are misshaped, typically crescent- or “sickle”-shaped due to a gene mutation that affects the hemoglobin molecule.
When RBCs sickle, they do not bend or move easily and can block blood flow to the rest of the body.
White Blood Cells (WBC)
- Also called Leucocytes
- Helps with fighting infection
- Have Nuclei
- Appears colourless
- ~1% of total Blood Volume BUT increase by more than DOUBLE when fighting infection
Types of WBC:
Granulocytes, Monocytes & Lymphocytes
Granulocytes
- Consists of neutrophils, basophils and eosinophils
Monocytes
- Can be further specialized as macrophages which destroy bacteria
- Granulocytes & Monocytes engulf and destroy bacteria
Lymphocytes
- It can produce a protein that can incapacitate pathogens allowing them to be detected and destroyed
Platelets
Fragments of cells that form when larger cells in the bone marrow break apart
No nucleus
Plays an important role in blood clotting
Blood Clotting
- Platelets are activated & clump together to form a plug to stop the bleeding when a blood vessel is damaged.
- Then the platelets release a protein called THROMBOPLASTIN.
- Thromboplastin activates a plasma protein called PROTHROMBIN along with CALCIUM IONS [ca++]
- PROTHROMBIN along with another plasma protein, called FIBIRNOGEN, is produced by the liver
- Prothrombin transforms into THROMBIN
- Thrombin act as an enzyme by splicing two amino acids from the fibrinogen molecule.
- Fibrinogen is converted into fibrin threads, which wrap around the damaged area, trapping RBC and more platelets to form a clot and stops bleeding
First Line of Defence: Non-Specific Immune Response
GOAL OF THIS FIRST LINE OF DEFENCE IS TO PREVENT THINGS FOR GETTING INTO YOUR BODY [BLOODSTREAM]
Ex. Skin, Mucus to trap foreign things, tears, eyelids, eyelashes, vomiting and blinking rapidly
Physical & Chemical Defense [SKIN]
- In your respiratory system mucus layers trap microbes and foreign particles and cilia (hair-like structures) sweep these particles away
- In your stomach, acids and enzymes destroy microbes that enter your body
Second Line of Defense: Non-Specific Immune Response
GOAL: If something enters the body DESTROY it.
It will do this through MACROPHAGES.
Third Line of Defense: Specific Immune Response
GOAL: Targeted attack on a particular invader
EX. B-cells & T-cells
Physical Defense
Skin provides a protective barrier so bacteria or viruses cannot enter your body
Chemical Defense
The skin has acid secretions that inhibit the growth of microbes
Body’s Response to the Second Line of Defence
Pus, Inflammatory Response, Fever
Pus
The remaining fragment of protein and White Blood Cell
Phagocytosis
The process by which a WBC engulfs and chemically destroys a microbe
Macrophages
One of the methods of the second line of defence.
Leucocytes (WBC) engulf invading microbes through phagocytosis or produce antibodies.
Special leukocytes called monocytes move from the blood to tissues and develop into macrophages.
Then they attach to microbes and use enzymes to destroy the macrophage
NOTE: Macrophages engulf the invader BUT the foreign antigens are not destroyed
Neutrophils
Another method of the second line of defence.
They are a type of WBC and are attracted to chemical signals given off by damaged cells.
They move to the infected tissues engulf the bacteria and release enzymes that break down the microbe and the leucocytes (Neutrophils)
Complement Proteins
A plasma protein that helps defend against invading microbes by tagging the microbe for phagocytosis, puncturing cell membrane or triggering the formation of a mucous coating
Lymphocytes
Type of WBC that produces antibodies
They roam the body searching for invaders
Antibodies protect the body based on marks on the foreign invader
T-cells
Seek out intruders and signal an attack, identify the invader by its antigens, a different T cell gives the information to a B cell
B-cells
Type of lymphocytes
Produces antibodies based on the foreign entities antigen
Antigen-Antibody Reaction
- Antibodies are specific (can only target the type of particle they are made for) and used to attack a specific type of foreign particle
- Antigens are markers on the foreign particle that the antibody attaches to forming an antibody-antigen complex, this prevents the foreign particle from doing what it wants to.
Helper T-cells
They read the shape of the antigen of the foreign invader and release a chemical messenger called lymphokine
Lymphokine
A protein produced by the T-cells that acts as a chemical messenger between other T- cells and B-cells
It causes the B-cells to divide and a second message is sent from the T cells to the B-cells causing the production of antibodies
Killer T-cells
It is activated by the Helper T-cell
A type of T-cells that puncture the cell membrane of infected cells which kills the cells
Allergy
This occurs when the immune system makes a mistake and attacks harmless visitors from the environment [Outside the body], causing the body to swell, itch or create mucus.
Memory B-cells
During the infection, they hold an imprint of the antigen so that the body is better equipped for future attacks
Suppressor T- cells
A T-cells that turns off the immune response
Illness
The immune system fails to recognize foreign invaders
Autoimmune disease
The immune system attacks the normal body cells, rather than protecting them.
Immunodeficiency
The helper T-cells are destroyed
Agglutination
Is the clumping of red blood cells that can clog blood vessels, block circulation and cause severe damage to organs.
The presence of antibodies causes this if mixed with an incompatible blood type
Type A Blood
RBCs have type A surface antigens
Plasma has anti-B antibodies
Type B Blood
RBCs - have type B surface antigens
- Plasma has anti-A antibodies
Type AB Blood
RBCs have - type A & type B surface antigens
- Plasma has NEITHER anti-A or anti-B antibodies
Type O Blood
RBCs - have NEITHER type A NOR type B surface antigens
- Plasma has BOTH anti-A and anti-B antibodies
Rheus Blood Type:
- People either have Rh+ (HAS antigen) or Rh- blood (DOES NOT have antigen)
- Generally, people with positive blood can receive from positive or negative but people with negative blood can receive only from negative
Rh Factor & Pregnancy
- If a mother is Rh- and a father is Rh+ the baby can be Rh+
- The Rh+ blood cells of the child may leak across the placenta into the mother’s bloodstream which causes the mother’s immune system to produce anti-Rh antibodies
- This is not a problem for the first pregnancy
- For any later pregnancies, these anti-Rh antibodies can destroy the child’s RBCs
Hemolytic Disease of the Newborn (HDN)
- Occurs when the anti-Rh antibodies the mother has crossed into the placenta and destroys the baby’s red blood cells
- Can cause brain damage, deafness and death
- As the red blood cells break down the liver produces a substance called bilirubin which causes jaundice (skin and tissue turn yellow) which is a sign when diagnosing HDN
-
Treatment:
- Blood transfusion for the baby or inducing early labour so the situation doesn’t get worse
-
Prevention:
- Now mother’s blood type is tested prior to the birth of the first child and an injection can be given just after the birth of the first child to prevent the mother’s body from producing antibodies
Antigen
- Marker (ID) on the cell’s membrane
- A substance that is usually a protein that stimulates the formation of an antibody
Antibody
- “Y” shaped proteins that attach to foreign antigens
- Slows down the foreign cells allowing the leucocytes to attack and kill the foreign cell
Main Function of the Respiratory System
- Ensure that oxygen is brought to each cell in the body and that carbon dioxide can leave each cell & be removed from the body.
- Respiration is the general term to describe this process
Respiratory Surface Area
- The area must be large enough for the exchange of oxygen & carbon dioxide to occur at a fast enough rate to meet the body’s needs.
Requirement For Respiration
Huge Respiratory Surface Area
Moist Environment
Stages In Respiration
Breathing
External Respiration
Internal Respiration
Cellular Respiration
Moist environment
Respiration MUST take place in a moist environment so that oxygen & carbon dioxide are dissolved in water
External Respiration
- Exchange of oxygen & carbon dioxide between the air and the **blood*
Takes place in the lungs
Breathing
- Involves inspiration (Breathing in/ Inhaling) & expiration (Breathing out/ exhaling)
Lower Respiratory Tract
Bronchi–> Bronchioles–> Alveoli
–> Lungs –> Pleural Membrane
Internal Respiration
Exchange of oxygen & carbon dioxide between the body’s tissue (Body cells) & the blood
Takes place within the body
Cellular Respiration
- A chemical reaction inside the cells using oxygen and nutrients to get energy
Upper Respiratory Tract
Nasal Passages –> Pharynx–> Epiglottis –> Larynx –> Trachea
PATH OF AIR:
Air enters through the nose & mouth
Nasal Passages
Warm, moisten and clean upcoming air
Pharynx
A.K.A. Throat
The passageway for air into the respiratory system
Glottis
The opening of the trachea
Epiglottis
A flap that makes sure the food doesn’t go into your lungs & air does go into your lungs, when a person swallows the epiglottis closes over the glottis
Trachea
A.K.A. Windpipe
Air moves down here after passing through the larynx.
Has a C-shaped cartilage rings that give it structure
Branches into TWO smaller passageways.
Larynx
A.K.A. Voice Box
Made of cartilage contains vocal cords
Pleural Membrane
Each lung is surrounded by a thin, double-layered membrane called the Pleural Membrane.
Prevents friction between the lungs and the chest walls during breathing.
Helps create a negative pressure within the pleural cavity which keeps the lungs inflated and allows them to expand smoothly as the chest cavity enlarges during inhalation..
Protects the lungs
Maintains lung position.
Bronchi
The smaller passageways that the trachea separated into
Bronchi is PLURAL, Bronchus is SINGULAR
Enter the RIGHT & LEFT lungs
Bronchioles
Each bronchus subdivides into smaller and finer tubes called bronchioles within each lung
Lobes
Each lung is divided into regions called lobes
Each lobe is made of many lobules that extend from each bronchiole
3 lobes on the RIGHT lung
2 lobes on the LEFT lung
Layers of the Pleural Membrane
OUTER LAYER: Attaches to the inside of the chest wall
INNER LAYER: Attaches to the lung
INBETWEEN FLUID: Fills the space between so that they attach together
This allows the lungs to expand & contract with chest movement
Alveoli
Each bronchiole ends in a cluster of tiny sacs
(SINGULAR: Alvelous)
This is where gas exchange occurs
Each alveoli is covered by a membrane called the alveolar wall
The alveolar wall is one cell thick and is surrounded by a network of capillaries
Inspiration (Inhalation)
- Intercostal muscle contract
- Diaphragm moves DOWN (contracts)
- The rib cage moves up & outwards
- The volume of the thoracic cavity increases
- Air pressure in the lungs decreases causing air to move INTO the lungs
Expiration (Exhalation)
- Intercostal muscles relax
- Diaphragm moves UP (Relax)
- Rib cage moves down & inward
- The volume of the thoracic cavity decreases
- Air pressure in the lungs increases causing air to move OUT of the lungs
External Respiration
Occurs in the LUNGS
Gases are exchanged between the alveoli and the blood in the capillaries
Structure for Gas Exchange
Walls of the alveoli & the capillaries each are one cell thick, which allows gases to diffuse through their membrane
How does air move from:
Air moves from HIGH-pressure to LOW-pressure
Chemoreceptors
A specialized nerve recpetor that is sensitive to specific chemicals
Carbon dioxide LOWERS the pH of the blood (Making it MORE acidic)
This is detected by the chemoreceptors in your brain which sends signals causing you to breathe deeper
INCREASE in carbon dioxide = INCREASE Breathing Rate.
What Regulates Breathing
Carbon Dioxide regulates breathing NOT oxygen.
How Gases are Exchanged
- Most of the oxygen & carbon dioxide exchange is done by simple diffusion (Movement from HIGH concentration —> LOW concentration)
- About 30% of the oxygen transfer happens by facilitated diffusion:
- Protein-based molecules in the alveoli “carry” oxygen across the membrane
- This DOES NOT require energy because it is still with the concentration gradient
- This is done to SPEED UP gas exchange
- This DOES NOT require energy because it is still with the concentration gradient
- Protein-based molecules in the alveoli “carry” oxygen across the membrane
Internal Respiration
- After the gas exchange between the capillaries & alveoli, the blood goes back to the heart and is then pumped into the body
- Gases are then exchanged between the blood and cells
Blood –> Body Tissues
Gas Transportation (Oxygen)
~99% of the oxygen is carried in the red blood cell by hemoglobin
This is called “OXYHEMOGLOBIN”
The rest of the oxygen is dissolved in the bloodstream
Gas Transportation (Carbon Dioxide)
- Slightly less than 1/4 of the Carbon dioxide is carried in the blood by hemoglobin- which forms carbaminohemoglobin
- ~7% is carried in the plasma
- ~70% is dissolved & carried in the blood as bicarbonate into ($HCO_3^-$)
- Carbonic acid $(H_2CO_3)$ is formed in the blood when a carbon dioxide molecule $(CO_2)$reacts with a water molecule $(H_2O)$
- $CO_2 +H_2O = H_2CO_3$
- The carbonic acid breaks down into a hydrogen ion $(H^+)$ and a bicarbonate ion – which occurs in red blood cells
- The $(H^+)$ combines with the hemoglobin and the bicarbonate ion diffuses out of the red blood cells into the plasma, which is carried to the lungs
- When the blood reaches the lungs the whole process is reversed to form carbon dioxide and water
Spirometers
Measure the amount of air that moves in and out of the lungs
Spirograph
A graph that measures
Tidal Volume, Inspiratory Volume, Expiratory Volume, Vital Capacity, Residual Volume
Tidal Volume
- The volume of air that is inhaled and exhaled in a normal breathing movement at rest (Breathing normally)
Inspiratory Reserve Volume
An additional volume of air that can be taken into the lungs beyond tidal/regular
Expiratory Reserve
- The additional volume of air that can be forced out of the lungs beyond tidal
Vital Capacity
- Calculated by:
- Tidal volume + Inspiratory Reserve Volume + Expiratory Reserve Volume
Residual Volume
Amount of gas that remains in the lungs even after full exhalation
Nephron
Filtering units within the kidney
There are approximately 2 million of them
Renal Vein
Carries blood AWAY from the kidenys that has been filtered & has minimal waste
Renal Arteries
Carries blood TO the kidneys that are filled with waste and need to be cleaned
Ureter
Tubes that carry urine from the kidneys to the bladder
Bladder
Stores urine
Urethra
Tube that carries urine from the bladder out of the body
Kidneys
Filters blood so that waste can be removed
Help to regulate blood pH
The major metabolic waste products are carbon dioxide, sodium, chloride, urea & uric acid
Ammonia
Produced as a waste product during metabolism
Very toxic so the liver immediately converts it to less toxic waste products that ultimately form urine
Uric Acid
Forms from the breakdown of nucleic acids (DNA & RNA)
Urea
Forms from the breakdown of the amino acid (PROTEIN)
Sections of the Kidney
Renal Pelvis
Cortex
Medulla
Renal Pelvis
Receives urine before sending it to the ureters
Cortex
The OUTER layer of the kidney, UPPER position of the nephron
Medulla
The INNER layer of the kidney, a LOWER portion of the nephron
Renal Vein
Takes CLEAN blood from the kidney to the heart
Renal Artery
Takes DIRTY blood AWAY from the heart TO the kidney
What are the 4 processes involved in the formation of Urine?
Glomerule filtration, Tubular reabsorption, tubular secretion, Water reabsorption
Afferent arteriole
A small branch of the renal artery that carries blood to the glomerulus
Efferent Arteriole
A small branch of the renal artery that carries blood AWAY from the glomerulus to the capillaries
Glomerular Filtration
Move water & solutes NOT proteins & blood cells from the plasma into the nephron.
Formation of urine STARTS here.
Forces some of the water & dissolved substance in the blood plasma from the glomerulus into the Bowman’s Capsule
2 Things that allow this to happen:
Permeability of the capillaries of the glomerulus.
Higher Blood Pressure
Filtrate
The filtered fluid
Permeability of the Capillaries of the Glomerulus
- The capillaries of the glomerulus have many pores in the tissue walls which allow water & dissolved substances to easily pass through BUT are small enough that proteins & blood cells can not enter.
Higher Blood Pressure
- The Blood pressure in the glomerulus is 4x greater than the rest of the body to force blood through for filtration
Tubular Reabsorption
Removes useful substances such as sodium from the filtrate and RETURNS them into the blood for reuse by body systems
Recovery of substances in the Proximal Tubule
- Approx 65% of the filtrate that passes through the entire length of the proximal tubule is reabsorbed and returned to the body
- Cells of the proximal tubule have lots of mitochondria
The majority of glucose is reabsorbed in the PROXIMAL TUBULE
Loop of Henle in the Proximal Tubule
- Function is to reabsorb water and ions from the glomerular filtrate
- The deeper portion of the loop of Henle enters a salty environment in the medulla
- The descending limb is permeable to water and only slightly permeable to ions
- The salty environment draws water out through osmosis leaving a high concentration of $Na^+$ at the bottom of the loop
- When the tubule goes around the bend and ascends up the permeability changes
- Becomes impermeable to water and slightly permeable to solutes causes sodium ions to diffuse from the filtrate and pass into blood vessels
- At the thick-walled portion of the ascending limb, sodium ions are moved out of the filtrate by active transport
- This does two things:
- Helps replenish the salty environment of the medulla
- Makes the filtrate less concentrated than the tissues and blood in the surrounding cortex tissue
Tubular Secretion
Moves wastes & excess substances from the blood into the filtrate
Tubular Reabsorption & Secretion in the Distal Tubule
- Active reabsorption of the sodium ions from the filtrate in the kidneys depends on the needs of the body
- Passive reabsorption of negative ions such as chloride occurs by electrical attraction
- Reabsorption of ions decreases the concentration of the filtrate, which causes water to be reabsorbed by osmosis
- Potassium (K+ ) are actively secreted into the distal tubule from the bloodstream
- Hydrogen ions (H+ ) are also actively secreted in order to maintain pH of the blood
- Other substances that happen to be in the body that are not naturally there (such as different medications) are secreted into the distal tubule
Water Reabsorption
Removes water from the filtrate and returns it to the blood for reuse by the body systems
Reabsorption from the collecting Duct
- Collecting duct extends deep into the medulla and the concentration of ions in the medulla increases (due to active transport of ions from the ascending limb of the loop of Henle)
- This causes passive reabsorption of water from the filtrate in the collecting duct by osmosis
Urine
- If a person is dehydrated the permeability to water in the distal tubule and collecting duct is increased so that more water is reabsorbed into the blood to conserve water in the body
- Reabsorption of water in the collecting duct causes the filtrate to be about four times as concentrated by the time it exits the duct
- Filtrate (which is now ~1% of the original filtrate volume) is now called urine and leaves the body
Osmorecpetors
Cells that are sensitive to osmotic pressure in the blood and surrounding extracellular fluids.
Most are found in the hypothalamus
Dehydrated
Blood plasma is too concentrated (You are DEHYDRATED)
Osmotic pressure INCREASES
This causes the osmoreceptors in your hypothalamus to send a signal to your pituitary gland (another part of your brain) which releases the hormone ADH (antidiuretic hormone)
Hydration
When blood plasma is too dilute (Too much water and not enough solute) the osmotic pressure DECREASES.
This causes the osmoreceptors in your hypothalamus to send a signal to stop or decrease the release of ADH
Increase in ADH
ADH travels to your kidney where it INCREASES the permeability of the distal tubule and collecting duct allowing more water to be reabsorbed in the blood
Decrease in ADH
When ther is too much water the osmoreceptors in your hypothalamus to send a signal to stop or decrease the release of ADH
- Distal tubule and collecting duct become less permeable to water and MORE water is excreted through urine
Maintaining Salt Balance
- Controlled by the hormone Aldosterone
- If the $Na^+$ concentration drops:
- Aldosterone stimulates the distal tubules and collecting ducts to reabsorb Na+
- This leads to passive reabsorption of chloride ions and water
- Aldosterone stimulates the distal tubules and collecting ducts to reabsorb Na+
- Aldosterone also stimulates the section of potassium ions into the distal tubules and collecting ducts if the concentration of potassium ions in the blood is too high
Maintaining pH
- pH of body fluids is about 7.4
The body can maintain this by:- Acid-base buffer system in the body by adding/removing hydrogen ions
- Changes to breathing rate – changes carbon dioxide levels
- Kidney’s controlling pH by excreting $H^+$ and reabsorbing $HCO_3^-$ [Bicarbonate ions]
Dialysis
Dialysis is a treatment that acts like an artificial kidney to clean your blood.
Diabetes Mellitus
CAUSE:
Low levels of insulin produced
by the pancreas, leading to
HIGH blood sugar
SYMPTOMS:
HIGH concentration of glucose
in the urine, frequent urination
Bright’s Disease (A.K.A. Nephritis)
CAUSE:
Inflammation of the nephron.
The Nephron can become
permeable to large solutes like
proteins or even blood parts
SYMPTOMS:
Proteins in Urine, Frequent
urination
Kidney Stone
CAUSE:
Development of crystalline
the formation called the kidney
stones
(Usually formed due to excess
calcium)
SYMPTOMS:
Extreme pain
Urinary Tract Infection (UTI)
CAUSE:
Bacterial or Viral infection
If the BLADDER is involved, it
is called CYSTITIS
If the URETHRA is involved
URETHRITIS
SYMPTOMS:
Painful burning secretion during
urination, feeling as if you need
to pee even if you DO NOT.
Bloody or brown urine
Renal Tubular Acidosis
CAUSE:
Accumulation of acid in the
BODY, due to a failure of the
kidney to properly filter blood
SYMPTOMS:
Tired, muscle weakness can lead
to kidney stones, urine has a
very HIGH pH (Very BASIC)
General Function of Muscles
Muscle tissue is specialized to convert CHEMICAL ENERGY into KINETIC ENERGY - energy of MOVEMENT
All muscles can contract (SHORTEN)- when they contract some part of the body or the ENTIRE body moves
Smooth Muscle Cells
- Long & tapered at each end
- Have one nucleus
- Usually arranged in parallel lines forming sheets
- Found in many parts of the body such as walls of certain blood vessels, the iris of the eye, walls of internal organs
- Contracts INVOLUNTARY
- Slower to contract than skeletal muscle, it can sustain prolonged contractions & does not fatigue easily
3 Types of Muscle Cells
Smooth Muscle
Cardiac Muscle
Skeletal Muscle
Cardiac Muscle Cells
- Forms the wall of the heart
- Cells are tubular and striated (Have bands of light & dark)
- Have ONE nucleus
- Branched- create a net-like structure
- Contracts INVOLUNTARY
Controlled by the nerves of the autonomic nervous system
Skeletal Muscle Cell
- Are tubular and striated
- “Meat” (Flesh) of animal bodies in skeletal muscle
- Contraction is VOLUNTARY- consciously controlled by the nervous system
- Humans have over 600 skeletal muscle
- Very long cells with many nuclei- length need for energy & materials require them to be controlled by many nuclei
- Usually referred to as fibres rather than cells
Tendon
Attaches each end of a muscle to a different bone
Skeletal Muscle Functions
- Supports the body contraction of skeletal muscle opposes the force of gravity & enables us to stand
- Allows body to move- allows for movement of bones, arms, legs, eyes, facial muscles, breathing
- Helps maintain body temperature- muscle contraction causes ATP to break down which releases heat that can be distributed throughout the body
- Helps to protect internal organs
- Stabilizes joint
Cooperation of Skeletal Muscle
- When muscles contract, they SHORTEN this means muscles can only PULL not PUSH
- When a muscle contracts, there needs to be a force available to later stretch it back to its returned state- to do this muscles work in pairs each performing the opposite action
- Ex. in your arm the bicep muscle causes the arm to flex (bend) as the muscle shortens and the triceps muscle, causes the arm to extend (straighten). When the triceps muscle contracts, this stretches the relaxed bicep muscle.
Skeletal Muscle Consists of bundles of fibres
Each skeletal muscle in the body lies along the length of a bone
- Muscle fibres can be up to 20 cm long and are organized into many longer bundles making up the muscle
- A layer of connective tissue wraps around each fibre, another layer wraps around each bundle of fibres, and another wraps around the whole muscle itself
- Blood vessels & nerves run between the bundles of muscle fibres
- Rich blood supply provides muscle fibres with nutrients & oxygen to power contraction & remove cell waste
- Nerves trigger & control muscle contractions
- Most of the volume of a muscle fibre consists of hundreds of thousands of cylindrical subunits called myofibrils
- Each myofibril is made of even finer myofilaments, which contain protein structures that are responsible for muscle contractions
- The rest of the volume of muscle fibre consists of numerous mitochondria & other organelles common to cells
Myosin
Protein that makes the muscle contracts
Thick myofilaments
Actin
Protein that makes the muscle contracts
Thin myofilaments
Myofilament
A thread of contractile proteins found within muscle fibres
Actin & Myosin are a type of myofilaments
Organization of Skeletal Muscle fibres
Muscle–> Muscle fibre bundles –> Muscle fibres –> Myofibrils –> Myofilaments
Tropomyosin
Prevents myosin from binding to actin
Steps of Muscle Contractions
- Calcium ions flood into sarcoplasm (cytoplasm of muscle cell)
- Calcium binds to the protein troponin which causes tropomyosin to shift position & expose the binding site on the actin molecule
- Myosin uses ATP
- Myosin head binds to the binding site on actin with the help of the protein tropomyosin
- Myosin pulls actin towards the center of the sarcomere (Muscle fibre)
- ATP causes detachment of the myosin head from actin
- Calcium releases & dissolves
- Troponin/ Tropomyosin release (Goes back to normal spot)
