SBI3U - Exam Review

Flashcards covering vitamins, mineral, digestive system structures and disorders, enzymes, respiration, circulation, blood components, genetics, plant biology, evolution and natural selection.

Vitamin A (Carotene)

Essential for vision, immune function, and skin health.

Vitamin B1 (Thiamine)

Helps convert food into energy and supports nerve function.

Vitamin C (Ascorbic Acid)

Supports immune function, aids in collagen production, and acts as an antioxidant.

Vitamin D

Helps the body absorb calcium and supports bone health.

Vitamin E

Acts as an antioxidant and helps protect cells from damage.

Magnesium

Supports muscle and nerve function, regulates blood pressure and helps in protein synthesis.

Potassium

Helps regulate fluid balance, muscle contractions, and nerve signals.

Sodium

Maintains fluid balance and is essential for nerve and muscle function.

Mucosa

The innermost layer that secretes mucus, enzymes, and acids to aid in digestion.

Submucosa

Contains blood vessels, nerves, and connective tissues that support the mucosa.

Muscularis

Made of three muscle layers that help churn and mix food.

Serosa

The outer protective layer that reduces friction between the stomach and surrounding organs.

Lower esophageal sphincter (LES)

Located between the esophagus and stomach; prevents stomach acid from moving back up into the esophagus.

Pyloric sphincter

Located between the stomach and small intestine; regulates food movement into the small intestine.

Duodenum

Microvilli absorb nutrients.

Jejunum

More folds than the duodenum, it continues the breakdown and absorption of proteins and carbs

Ileum

Less villi than duodenum and jejunum, continues to absorb nutrients

GERD

Stomach acid back into esophagus. caused by diet, medication, etc

Inflammatory Bowel Disease

Inflammation of the colon and small intestine

Ulcers

Open sores in the lining of the digestive system

Type 1 Diabetes

When the pancreas can't produce insulin

Type 2 Diabetes

Cells can't absorb insulin/ pancreas doesn't produce enough

Gallstones

Hard rocks in gallbladder

Salivary Enzyme

Origin: salivary glands, Act/pH: mouth/7, Digests: starch, glycogen, Products of Digestion: maltose

Pancreatic Enzyme

Origin: pancreas, Act/pH: small intestine/8, Digests: starch, glycogen, Products of Digestion: maltose

Carbohydrases (sucrase, maltase, lactase)

Origin: small intestine, Act/pH: small intestine/8, Digests: sucrose, maltose, lactose, Products of Digestion: gluctose + fructose, glucose, gluctose + galactose

Pancreatic Lipase

Origin: pancreas, Act/pH: small intestine/8, Digests: lipids, Products of Digestion: fatty acids, glycerol

Proteases (pepsin, trypsin, chymotrypsin)

Origin: stomach, pancreas, pancreas, Act/pH: stomach/1-2, small intestine/8, small intestine/8, Digests: protein, small polypeptides, small polypeptides, Products of Digestion: peptides, smaller peptides x2

Peptidases

Origin: pancreas, small intestine, Act/pH: small intestine/8, Digests: peptides, Products of Digestion: smaller peptides than amino acids

4 Stages of Respiration

1. Breathing (ventilation) - air enters and leaves the lungs (inspiration and expiration) 2. External Respiration (gas exchange) - the exchange of oxygen and CO2 between the inside of the lungs and the blood that occurs simultaneously 3. Internal Respiration - exchange of O2 and CO2 between the blood and the body's tissue cells that occur simultaneously 4. Cellular Respiration - energy-releasing reactions in cells

3 Requirements of Respiratory System

1. Must be large enough to meet the body's needs 2. Must be moist so gasses can dissolve 3. Must be thin and close to circulatory fluid

Outer Skin

Organism must live in moist environment and have high surface to body volume ratio Eg. Worm

Gills

Folds on outer body which increase surface area available for gas exchange ~ Oxygen from water diffuses across the gill surface into capillaries ~ Fish use counter-current system O2 and CO2 flow in opposite directions to the flow of O2-rich water

4 Structural Features of Respiratory Tract

1. Thin semi-permeable membrane where diffusion can occur 2. Large surface area for gas exchange 3. Good supply of blood 4. Breathing System

Mouth, Nose, Nasal Cavity

Air is warmed and moistened here before it travels to the lungs ~ Cilia line the passages with mucus to trap dust

Pharynx

Connects the mouth and nasal cavity to the larynx ~ Tonsils and lymph tissues are found here

Epiglottis

Flap of tissue that closes the glottis off and prevents food from entering the trachea

Larynx (Voice Box)

Surrounded by thick cartilage ~ Made up of 2 ligaments ~ Cords vibrate to produce sound

Trachea (Windpipe)

Made up of rings of cartilage ~Lined with cilia ~ Throughout the upper respiratory tract, mucus is secreted to trap foreign particles (0.9L/day)

Lower Respiratory Tract

Trachea branches into 2 bronchi, which further divide into a network of bronchioles, which are also lined with cilia ~ Each bronchiole ends in a cluster of alveoli ~ The wall of alveoli is 1-cell thick

Mechanics of Breathing

1. Inhalation - Diaphragm contracts, causing it to shorten and flattenExternal intercostal muscles, located between each rib, contract and pull the ribs outward and upwardTogether, they reduce the pressure inside the lungs, filling them with air 2. Exhalation - Diaphragm relaxes and moves back up External Intercostal muscles relax, allowing the ribs to fall inwards and downwards Together, increasing the pressure inside the lungs, causing air to flow out

Inspiratory Reserve Volume (IRV)

The extra air you can inhale after a normal breath.

Tidal volume

The amount of air you breathe in and out during normal breathing.

Expiratory reserve volume

The extra air you can exhale after a normal breath.

Vital capacity

The total air you can exhale after a deep inhale (inspiratory reserve + tidal volume + expiratory reserve).

Residual volume

The air left in your lungs after you exhale as much as possible.

Total lung capacity

The total amount of air your lungs can hold (vital capacity + residual volume)

Lung Cancer 2 Types

1. Non-Small Cell Lung Cancer 2. Small Cell Lung Cancer

NSCLC

Size: Large, mature cells - Spread: Less aggressive - Risk: 90% of patients have a history of smoking, 10% don't - % of all cancer: 85% of all lung cancer - Subcategories: Adenocarcinoma, large cell carcinoma, squamous cell carcinoma

SCLC

Size: Smaller, flatter, immature cells - Spread: Very aggressive - Risk: Typically occurs in females with a long history of smoking - % of all cancer: 15% of all lung cancer - Subcategories: Small-cell carcinoma, combined small-cell carcinoma

Smoking

Tobacco smoke contains 7,000 chemicals, 60 of which are known to cause cancer - Cancer Chemicals: tar, carbon monoxide, arsenic, ammonia, acetone, toluene, methylamine, pesticides, polonium - Smoking leads to Chronic Bronchitis - People who smoke are 25 times more likely to get lung cancer or die from lung cancer

Chronic Obstructive Pulmonary Disease

Inflammation to lung "pipes" preventing air flow in/out of lungs - Caused by exposure to cigarette smoke/ air pollution

Influenza

Caused by influenza viruses - Typical symptoms DO NOT include vomiting/diarrhea - Symptoms: fever, cough, sore throat, body aches, fatigue

Asthma

Inflammation and narrowing of the airways in the lungs - Symptoms: Asthma attack (shortness of breath, wheezing, coughing, tightened chest) - Triggers: allergens, respiratory infection, exercise, irritants

Pneumonia

Serious respiratory infection that inflames the alveoli (air sacs) in one or both lungs, causing them to fil with pus or fluid - Symptoms: fever, a cough with phlegm, and difficulty breathing

Performances of Circulatory System

1. Transport gasses, nutrient molecules, and waste 2. Regulate internal temperatures 3. Transport chemical substances (hormones) around the body 4. Protect against blood loss from injury, diseases, and toxic substances

Features of the Circulatory System

1. Fluid that transports materials through the body (blood) 2. Network of tubes in which the fluid circulates (veins) 3. A pump that pushes the fluid through the tubes (heart)

Open Circulatory System

Fluid flows freely within the body and makes direct contact with/organs and tissues - Circulating fluid = Hemolymph (blood and tissue fluid)- 1 or more hearts push blood through vessels, when the heart relaxes, hemolymph is drawn back to the heart through open-ended pores - Main function: transporting nutrients & waste Eg. Insects, crustaceans

Closed Circulatory System

Blood is kept physically contained with vessels - Blood flows a continuous fixed path & is confined to a network of vessels that keep the blood separate - Substances diffuse between circulatory system and other cells Eg. Humans

Atrium

Collects blood from the body & pumps it to the ventricle

Ventricle

Pumps blood around the body

2-Circuit Circulatory System

The more complex system separates circulation to the lungs and the rest of your body by a 4-chambered heart - Pulmonary Circuit: moves blood to the lungs for gas exchange - Systemic Circuit: moves blood to rest of the body tissues to deliver O2, nutrients, and other substances

Cardiac Circulation

Blood flow within the heart

Blood Vessels

1. Arteries - highest pressure pulse 2. Veins - lowest pressure pulse 3. Capillaries - moderate pressure, leaky walls, gas exchange

Arteries (and arterioles)

Carries blood away from heart - Highest pressure due to 3 structural layers:

Veins (and venules)

Less elastic and greater volume (2x of arteries) - Muscles contract, squeezing the veins, allowing blood to be pumped back to heart - 1-way valves prevent backwards flow

Capillaries

Smallest blood vessel, reaches every corner of the body - Single layer of endothelial cells which controls flow of substances in and out of cells - Unlike veins and arteries, blood flow through capillaries is not controlled by the nervous system - Have pre-capillary sphincters that contract and relax depending on the blood flow needed in the specific area

Aorta

Main artery of the body, distributing to all organs

Carotid

Neck region

Jugular

Located on side of neck - Affects head region

Hepatic

Associated with liver

Renal

Kidney area

Vena Cava

Largest VEIN in the body - Principal vein of the body, brings deoxygenated blood back to heart

Celiac

Serves coelom (major body cavity) & contained organs (ex. stomach)

Blood Pressure

Every time the heart beats, blood surges through the arteries, causing an increase in pressure -> arteries stretch in diameter (systolic pressure) - Diastolic pressure: when the arteries relax between contractions

Average Blood Pressure

Healthy BP: 120/80

Blood Tissue

Blood tissue is made of 2 main elements 1. Plasma: 55% of blood2. Cells: 45% of blood volume

Plasma

Made of water (92%), 7% dissolved blood proteins (albumin, globulins, fibrinogen), and 1% other substances (dissolved gases, sugars, minerals, fatty acids, and waste products)

Cells

Consists of RBCs, WBCs, and platelets that are formed in bone marrow

Red Blood Cells

Erythrocytes - Make up 44% of total blood volume - Biconcave disks that don't contain a nucleus- Specialized for O2 transport (hemoglobin)

White Blood Cells

Leukocytes - Make up 1% of total blood volume - All WBCs contain a nucleus

Platelets

Thrombocytes - When a blood vessel is broken, platelets stick to collagen fibres and create a mesh that traps more and more platelets

Origins of Blood Cells

RBC: Bone marrow WBC: Bone marrow, lymph glands Platelets: Bone marrow, lungs

Size of Blood Cells

RBC: Small (8 micrometers) WBC: Larger (10 micrometers) Platelets: Smallest (2 micrometers)

Function of Blood Cells

RBC: Carry O2 and CO2 WBC: Engulf foreign particles/ form antibodies Platelets: Play a role in clotting of blood

Life Span of Blood Cells

RBC: 120 days WBC: A few hours - a few days Platelets: 2-8 days

Genetics

the study of heredity and variation of inherited characteristics

DNA

nucleotides - composed of a nitrogenous base, phosphate group, and a sugar (phosphate and sugar form the backbone)

Adenine + Thymine

2 carbon-nitrogen ring bases

Cytosine + Guanine

1 carbon-nitrogen ring bases

Diploid

2 sets (1 from each parent) - somatic (body) cell - 2n chromosomes

Haploid

1 set of chromosomes -n - gamete cells

Asexual Reproduction

1 parent - offspring is identical (same genetic code) - usually occurs in single-cell organisms/plants

Fission

simplest form - involves a cell duplicating its genetic information and splitting into 2

Spore Reproduction

occurs in fungi, bacteria - spores produced are tiny, thick-walled and very resistant structures

Budding

single cells form a "bud" which becomes larger and then pinches off from the parent

Cloning

involves putting a cell in a liquid nutrient and adding chemicals to cause it to grow and differentiate into exact duplicates

Vegetative Propagation

some plants reproduce by forming structures that can grow into a whole new plant when separated from the parents

Sexual Reproduction

occurs in multi-cellular organisms - offspring receives half their genetic code from each parent

Internal Fertilization

the union of gamete cells inside the female body