Chapter 10

Question 1

Chemicals from food you eat are used to….

Answer 1

provide building blocks to build molecules, to generate energy for your body’s activities, & to assemble essential nutrients that your body cannot produce.

Question 2

Food supplies over ___ substances that your body needs but cannot produce itself

Answer 2

40

Question 3

Nutrients are

Answer 3

the chemicals in the food you eat that help your body perform all its functions
- there are 6 types of nutrients in food: carbohydrates, proteins, fats, vitamins, minerals, & water.

Question 4

Macronutrients are

Answer 4

nutrients that you need in large amounts daily.
- Macronutrients = Carbohydrates, proteins, fats, & water

Question 5

Micronutrients are

Answer 5

nutrients that you need less of on a daily basis
-Micronutrients = Most vitamins & minerals

Question 6

The food you eat usually contains _______ & ______ molecules

Answer 6

large, complex
- they are too big to pass through cell membranes & are not exactly the same as the smaller ones found in your body
- the digestive system must dissemble the food you eat into smaller molecules –> these molecules then become sources of energy, or assemble them into more complex molecules & use them to build and maintain cell structure and function.
- Ex. cheese is made up of proteins that are too large for our cells to use in their present state. Your digestive system dissembles them into their basic “building block” molecules. Your cells then use them to build your own proteins

Question 7

All organisms use the ______ components to make their molecules

Answer 7

same
- Ex. lions, pandas, humans, & trees make their proteins from the same 20 kinds of building block molecules

Question 8

Carbohydrates are (3)

Answer 8

compounds made up of Carbon, Hydrogen, & Oxygen atoms and are major source of energy for your body.
- U can use carbs as an energy source just minutes after a meal or u can store them for later use
- Foods with simple carbs include sugars from fruit, honey, milk

Question 9

Glucose is (4)

Answer 9

is a type of sugar molecule that is a major source of fuel supply for the work done by your cells
- ur cells break down glucose molecules & extract their stored energy
- ur cells use carbon chains of simple sugars as raw material to manufacture other kinds of molecules
- glucose molecules that ur cells don’t use immediately are incorporated into larger carbs or are used to make fat molecules

Question 10

Starches are

Answer 10

complex carbs.
- they are found in foods like whole-grain cereals, bread, rice, & potatoes.
- complex carbs are broken down by ur digestive system into simple sugars –> the simple sugars are absorbed into blood & carried to cells in the body –> excess blood sugar is converted into glycogen

Question 11

Glycogen is (3)

Answer 11

a chain of many glucose molecules
- in humans, most glycogen is stored in the liver and in muscle & fat cells. –> When the body needs energy, it breaks down glycogen, releasing glucose.

Question 12

Fibre/Cellulose (3)

Answer 12

is a type of complex carb
- our digestive system can’t break it down but u need it to include it in ur diet as fibre supplied bulk to help ur muscles move food & wastes through ur digestive system.
- they may have other benefits like reducing the risk of heart disease.

Question 13

A protein is (5)

Answer 13

a complex molecule that is constructed from 20 kinds of smaller molecules called amino acids
- they contribute to almost all ur day-to-day functions. Ex. proteins form hair & muscles, and they provide long-term nutrient storage
- some proteins circulate in the blood & defend the body from harmful micro-organisms
- Other proteins convey messages from one cell to another
- some proteins work with enzymes to control the chemical reactions in a cell

Question 14

Enzymes are

Answer 14

proteins that speed up specific chemical reactions without being consumed in the reaction

Question 15

Essential amino acids (5)

Answer 15

are the 8 amino acids that your cells cannot make from other molecules
- if u lack even 1 essential amino acid, you cannot make protein properly.
- Animal products like meat, milk, eggs, & cheese provide all 8 essential amino acids
- those that don’t eat animal products must eat combinations of plant foods to obtain all the essential amino acids
- some vegetarian combos of complete protein include corn & beans, rice & lentils, and hummus with pita bread

Question 16

Fats (5)

Answer 16

AKA lipids
- are molecules formed from fatty acids & glycerol.
- fats store energy in ur body & help ur body absorb fat-soluble vitamins.
- fatty tissues cushion ur organs & provide ur body with insulation.
- there are several types of fat

Question 17

Saturated Fats (5)

Answer 17

have only single bonds between carbon atoms in the fatty acids
- Each of these carbon atoms has the maximum number of hydrogen atoms, so the fat is called “saturated”
- Saturated fats= most animal fats like lard & butter
- Diets rich in saturated fats may promote fat deposit build-ups in blood vessel walls which can reduce blood flow & contribute to heart disease.
- Only a small percentage of ur daily intake of fats should be saturated fats

Question 18

Unsaturated Fats

Answer 18

have at least one double bond in a fatty acid chain so we say it’s “unsaturated”
- found in fruits, vegetables, nuts, seeds, & fish
- Unsaturated fats like olive oil & sunflower seed oil, are usually liquids @ room temp
- Small amounts of unsaturated fats are an important part of a healthy diet

Question 19

Trans Fats

Answer 19

AKA Hydrogenated fats
- they are unsaturated fats have been hydrogenated, meaning they have been processed to accept more hydrogen atoms
- they are solid @ room temp & have a longer shelf life than other unsaturated fats. –> Ex. margarine that is solid @ room temp is trans fat
- They are often used in frying fast foods
- they should be avoided as consuming trans fats as they contribute to heart disease & other health problems

Question 20

Vitamins are

Answer 20

organic nutrients that u need in small amounts to regulate ur body processes & perform chemical reactions
- organic nutrients = nutrients that contain carbon
- if u picture carbs, proteins, & fats as building blocks, vitamins are the tools to help put them together.

Question 21

What are the 2 types of vitamins?

Answer 21

water-soluble & fat-soluble
- water-soluble vitamins cannot be stored in ur body & should be included in ur everyday diet. Ex. vitamin C, the B vitamins
- small amounts of fat-solube vitamins can be stored in the fatty tissue of ur body for future use. Ex. Vitamins A, D, E, K

Question 22

Minerals are

Answer 22

inorganic nutrients & do not contain carbon
- u need a variety of minerals in ur diet like calcium, iron, phosphorus, copper, sodium, & zinc to perform many different tasks. –> Ex. u use calcium to make bones & teeth.
- u need to consume mineral-rich foods each day to replace the minerals u lose in sweat, urine, & digestive waste

Question 23

Vitamins & , minerals are found naturally in

Answer 23

many foods like meat, eggs, dairy products, whole-grain products, tofu, green leafy vegetables, & some fruit
- people who are not able to eat enough of a variety of foods from the basic groups sometimes take vitamin & mineral supplements
- however large doses of vitamin & mineral supplements may be harmful, so its important to read the recommended dose on labels & consult ur heath practitioner.se

Question 24

Why is water the most important nutrient?

Answer 24

• ur every cell needs water to complete its processes
• many of the body’s chemical reactions take place in water
• water makes up the bulk of blood,
  extra-cellular fluid, & other bodily fluids
• many guides recommend 1litre of water daily–> more when ur physically active or its hot
• without enough water to replace what u lose through sweat, urine, & respiration, u can suffer from dehydration, which leads to problems with many body systems

Question 25

Converting food into energy

Answer 25

- During cellular respiration, molecules like glucose make cellular energy by reacting with oxygen. - 40% of energy from food is converted into energy for performing cell functions - 60% is converted into thermal energy, radiating from ur body as heat --> heat generated by cellular respiration is not wasted: retaining some heat enables ur body to regulate its temp. --> when exercising, ur cells increase cellular respiration rate. That's why u feel warm after exercising. ---> ur body loses heat through sweating & other cooling methods.

Question 26

When u sit in class, u radiate about as much heat as a ______ light bulb

Answer 26

100-W

Question 27

A calorie is

Answer 27

the amount of energy required to raise the temp of 1g of water by 1 degrees Celsius.

Question 28

Dietary Calories

Answer 28

calories u will learn about in this unit - written with an uppercase C - 1 dietary calorie = 1000 calories

Question 29

Calories in fats, carbs, & protein

Answer 29

Fats are energy rich: 9 calories per gram Carbs & proteins: 4 calories per gram WHY? - The carbon atoms in fats usually have more carbon-to-hydrogen bonds than carbon atoms in carbs or proteins. --> breaking these bonds releases a great deal of energy, so a 1g of fat releases more energy than 1g of protein or carbs

Question 30

Female teenagers need ______ calories & male teenagers need ______ calories for the basic metabolic processes that sustain life plus energy for an active lifestyle.

Answer 30

2200, 2500

Question 31

Daily physical activity of at least ____ minutes helps burn any excess calories & maintain a healthful weight. It also strengthens the _______, _______, & _________.

Answer 31

30, heart, bones, muscles

Question 32

Nutrient Vs percentage of total daily calories recommended

Answer 32

Carbs: 45-65% proteins: 10-30% Fats: 25-35%

Question 33

The science of nutrition is the study of .....

Answer 33

food & its effects on the body

Question 34

Nutrition Labels

Answer 34

- Health Canada requires that nutritional info be placed in a standardized manner on all packaged foods in order to identify the nutritional value --> they show nutrient contents & nutritional claims in a format that is easy to read & understand - reading them helps track daily requirements for important nutrients like dietary fibre, protein, vitamins, & healthy fats as well as unhealthy fats, sugar, & sodium that contribute to heart disease, high bp, & stroke

Question 35

A nutraceutical is

Answer 35

- is a substance that is purified from foods and taken like a medicine to provide health benefits including disease prevention. Ex. omega-3 fish oil pill that's taken as a supplement - called nutraceuticals or functional foods is a new food industry that's based on the idea that foods can be disease-fighters

Question 36

Functional Food is

Answer 36

a food that has health benefits, including disease prevention, that are beyond the normal nutritional benefit of the food - Fruit & veggies with high levels of vitamin A, C, E, & beta-carotene are identified as good candidates - Orange juice: rich in calcium, Eggs: rich in omega-3, milk: rich in vitamin D - Ex. Study by National Cancer Institute in the USA states that foods like garlic, cabbage, carrots, licorice, soy, & ginger as possible cancer-fighters. - Ex. wheat bran can reduce risk of colon & breast cancer. - rn Canada has 100s of companies in food industry & is becoming a world leader in such foods supply

Question 37

Probiotics are

Answer 37

foods that contain substances that support health and that may help to strengthen the body's natural defence against disease - Probiotic products like probiotic yogurt, help increase beneficial bacteria back into the large intestine - it is one of the fastest-growing areas of dietary products

Question 38

The search to understand how our bodies digest food actually began ___________ of years ago

Answer 38

hundreds - In 1700s, Lazzaro Spallanzani (natural history proff) devised a simple experiment to determine how food is broken down. --> subjects (humans & birds) swallowed a small sponge attached to a thread. after time, he pulled out the sponge to examine. --> He observed that the juice that filled the sponge could break down meat. --> concluded that an area in the body produced special juice that could digest food - Spallanzani's theory debunked the previously held theory that food was "cooked" in the heat of stomach and that's how it is broken down. - Scientists today, who use technology now, are "standing on the shoulders" of curious thinkers like Spallanzani who lived 100s of years ago

Question 39

Industry experts expect that there will be continued growth in the "_________" food business

Answer 39

Designer - the demand for food designed to fight disease will increase as consumers become more knowledgeable about health benefits of foods & rising health care cost

Question 40

Canada's Food Guide to Healthy Eating

Answer 40

- It provides the public with needed info to make healthy food choices - Recommended servings on PAGE 283 - According to the guide ... 1 serving of vegetables & fruit= medium fruit or 125mL vegetables 1 serving of grain = 1/2 bagel, or small waffle 1 serving of milk & alternatives = 200mL milk, or 200mL yogurt 1 serving meat & alternatives = 30mL peanut butter or 75g chicken - Other guidelines in TABLE ON PAGE 283

Question 41

To eat in a healthy way, you need to eat the _____ foods & the ____________ of different foods

Answer 41

right, right amount

Question 42

What are the 4 stages of Food Processing? (just list them in order of occurrence)

Answer 42

1) Ingestion 2) Digestion 3) Absorption 4) Elimination

Question 43

Stages of Food Processing: Ingestion

Answer 43

- it's the act of eating or drinking

Question 44

Stages of Food Processing: Digestion

Answer 44

- it's the process of breaking food down into molecules that are small enough for the body to absorb - There are 2 types of digestion: Mechanical & Chemical

Question 45

Mechanical Digestion

Answer 45

like chewing & churning of stomach, grinds food into smaller pieces, increasing it's surface area (which makes chemical digestion easier)

Question 46

Chemical Digestion

Answer 46

- is breaking the chemical bonds within the large molecules of carbs, fats, & proteins into smaller molecules during hydrolysis

Question 47

Hydrolysis is

Answer 47

a process that breaks bonds in food molecules by adding water to them in the presence of specific enzymes.

Question 48

What is each Macronutrient broken down into?

Answer 48

Fat --> glycerol + fatty acids = used to build fats Protein --> amino acids = used to build proteins Carbs --> sugars (like glucose) = source of energy & source of chain of carbon atoms that ur body can used to construct other molecules containing carbon.

Question 49

Stages of Food Processing: Absorption

Answer 49

- It's when cells absorb small molecules like amino acids and simple sugars in the small intestine. - from there, they enter the circulatory system where the molecules are transported in the blood to body cells, where they combine to make bigger molecules or are broken down to provide energy. - If there are more molecules then needed immediately, they are converted into fat for storage.

Question 50

Stages of Food Processing: Elimination

Answer 50

- It's the process of removing from the digestive tract any undigested materials. --> these materials travel through the large intestine & are eliminated as feces.

Question 51

In a digestive sac,...

Answer 51

food enters and wastes exit through the same opening - Ex. a sea anemone has a digestive sac

Question 52

An Alimentary Canal is

Answer 52

AKA gastrointestinal tract a digestive tract with 2 openings, a mouth & an anus --> Food enters through the mouth at one end and is churned & mixed as it travels along the tube. --> Further along, nutrients are absorbed from the digested food & then the wastes are disposed through the anus - Alimentary canals are more efficient than digestive sacs for obtaining nutrients from food as it has more specialized regions for processing food. - more complex animals have an alimentary canal

Question 53

Alimentary Canal Length

Answer 53

- The length of an animal's alimentary canal is often correlated with diet. --> typically herbivores & omnivores have longer alimentary canals, relative to their body size, than omnivores --> this is cuz vegetation is harder to digest as it has cell walls. --> longer alimentary canal provides more time for digestion & more surface area of nutrient absorption. - In humans & many others, the alimentary canal is much longer than distance between mouth & anus. --> Ex. A person 1.8m tall can have a 9-m alimentary tract. It fits cuz portions with & loop back & forth

Question 54

If the body is made out of the nutrients u digest, how do we prevent self-digestion?

Answer 54

- by digesting food in specialized organs

Question 55

6 main organs that make up the alimentary canal

Answer 55

- mouth, pharynx, esophagus, stomach, small intestine, & large intestine

Question 56

Accessory organs & glands of digestive system

Answer 56

include salivary glands, pancreas, liver, & gallbladder, which secrete digestive juices in the alimentary canal

Question 57

6 Main Organs: Mouth

Answer 57

- functions in ingestion & beginning of digestion - teeth & tongue = mechanical digestion --> tongue moves food towards teeth and down the throat --> Incisors, cuspids, & bicuspids cut into & tear food. --> molars grind & crush food into fine paste, making it easier to swallow & increases surface area for easier chemical digestion - the salivary glands secrete saliva for chemical digestion

Question 58

6 Main Organs: Pharynx is

Answer 58

the upper portion of the throat. It's a short tube shared by the digestive & respiratory system - when u swallow, the epiglottis (a cartilage flap) temporarily seals off the airway & prevents the food from moving into the air passageway as it passes through the pharynx & into the esophagus.

Question 59

In a typical day, salivary glands in your mouth secrete more than ___ of saliva

Answer 59

1L

Question 60

Saliva is

Answer 60

a watery liquid that contains digestive enzymes, mucus, & other chemicals to chemically digest food in mouth - Digestive enzymes in saliva include amylase, which breaks down chemical bonds in starches (a carb), like pasta & bread, to form sugars. --> that's y if u chew on starchy food for long, it will taste sweet. - Another enzyme, lysozyme, helps fight infection by digesting cell walls of bacteria that may enter the mouth. - mucus (a sticky substance) in saliva, lubricates food so that it can slide down the tube without harming the tissues that line the tube. - Chemicals in saliva neutralize certain acids in food, preventing teeth from decay - saliva also moistens food & makes it easier to chew.

Question 61

Bolus is

Answer 61

chewed clump of food

Question 62

6 Main Organs: Esophagus is

Answer 62

a long, muscle-encased tube which connects the pharynx to the stomach - Even though the esophagus is vertically oriented in the body, gravity plays no role in pushing the bolus down the esophagus --> instead, its pushed through peristalsis

Question 63

Peristalsis

Answer 63

is the involuntary contraction and relaxation of longitudinal and circular muscles in a wave-like motion throughout the digestive tract, allowing for the propulsion of the food from the pharynx to the anus

Question 64

a sphinctor is

Answer 64

a muscular valve that acts like a door. - GOOGLE: A ring-shaped muscle that relaxes or tightens to open or close a passage or opening in the body

Question 65

Heartburn

Answer 65

- not related to heart - a sphincter at the end of the esophagus (cardiac sphinctor) closes to keep food from coming back up the stomach. - if this muscle opens at inappropriate times, like when u overeating, acid from the stomach can flow back into the esophagus, causing a burning sensation: heartburn

Question 66

6 Main Organs: Stomach is

Answer 66

an elastic, muscular sac that continues the chemical & mechanical digestion of food. - with accordion-like folds & highly elastic wall, ur stomach can stretch to hold up to 2L of food & drink, enough for ur body's needs for many hours

Question 67

Chemical Digestion in Stomach

Answer 67

- bolus is bathed in gastric juice - HCI in gastric juice breaks apart the cells in food & kills bacteria swallowed with food - 1 gastric enzyme, pepsin, helps break large protein molecules into smaller molecules - Mucus lubricates & protects the stomach wall from the HCI, preventing stomach from eating itself.--> even with mucus, cells of stomach are eroded and every 3 days, enough new cells are generated to completely replace the stomach lining. - gastric glands don't secrete gastric juice constantly. --> when u see, smell, or taste food, a brain signal is sent to ur stomach to stimulate the gastric glands to secrete gastric juice. --> ur gastric glands secrete up to 3L of gastric juice daily.

Question 68

Mechanical Digestion in Stomach

Answer 68

- about every 20 seconds, the stomach contents are mixed by churning of stomach wall. --> turns bolus into acid-rich liquid called chyme. - The muscles contract, creating churning motion that stirs the chyme & eventually forces it into small intestine --> flow of chyme into small intestine is regulated by a sphincter. - it typically takes 2-6 hours for the stomach to empty.

Question 69

6 Main Organs: Small Intestine is

Answer 69

a long (6m), narrow (2.5 cm) tube where digestion is completed & absorption of most nutrients takes place. - Digestion takes place in first portion, and absorption takes place along the rest of the length. - peristalsis move chyme along the intestine, a journey that takes about 3-5 hours

Question 70

Digestion in Small Intestine

Answer 70

first part of small intestine = duodenum - fats are undigested till the duodenum cuz they are insoluble in water So how do fats undergo hydrolysis? - in duodenum, chyme mixes with several digestive juices like bile. --> Although bile has no enzymes, it has substances that prepares fats for hydrolysis --> fats tend to clump together, making it difficult for enzymes to reach the molecules (less surface area). --> bile separates small fat droplets, which enables digestive enzymes to break down fats more efficiently - Pancreatic juice contains enzymes that further break down carbs, proteins, & fats. - Pancreatic enzymes, along with enzymes secreted by the lining of the small intestine, complete the chemical digestion of food.

Question 71

Bile is

Answer 71

a yellow or greenish alkaline liquid produced by liver (body's greatest internal organ) - bile is stored in a sac-like structure called the gallbladder until it's secreted into the duodenum

Question 72

Pancreatic juice is

Answer 72

a clear alkaline liquid that neutralizes the acidic chyme & contains enzymes that further break down carbs, proteins, & fats. - Pancreatic enzymes, along with enzymes secreted by the lining of the small intestine, complete the chemical digestion of food.

Question 73

Absorption in Small Intestine

Answer 73

- the small intestine is highly specialized for absorbing nutrients --> its wall is folded into many small finger-like projections called villi (singular villus). The cells lining each villus have microscopic projections called microvilli. - the villi increase the surface area of intestine, making absorption more efficient - at its core, each villus has a network of microscopic blood vessels & a small lymph vessel. --> once fatty acids & glycerol are absorbed, these building blocks are recombined into fats that are then transported into the lymph vessel. --> Sugar & amino acids are absorbed into bloodstream through blood vessels in each villus

Question 74

Where does the nutrient-rich blood travel to once absorbed into bloodstream by the blood vessels in villi? (2)

Answer 74

-nutrient-rich blood from small intestine travels to liver, where many nutrients are converted into new substances like protein. - The liver also modifies & detoxifies substances absorbed by the digestive tract before the blood carries these materials to the heart for distribution to the rest of the body.

Question 75

6 Main Organs: Large Intestine is (6)

Answer 75

AKA colon is a short (1.5m) wide (5cm) tube - undigested food passes through a sphincter from the small intestine to this one. - As material enters the large intestine, it passes by a small sac-like organ called appendix --> in some mammals, the appendix processes cellulose & other materials. --> In humans, the appendix contains white blood cells & plays a role in immunity. - the large intestine absorbs any access water from this waste, making it more solid - the wastes move along colon by peristalsis, taking about 12-24 hours

Question 76

Water absorption in large intestine (3)

Answer 76

- Saliva, gastric juice, & other digestive juices contain large amounts of water. --> together, about 7L of fluid are secreted into the alimentary canal each day --> some is absorbed with nutrients in small intestine - the large intestine absorbs most of the remaining water - together, the small & large intestine absorbs 90% of the water that enters the alimentary canal

Question 77

Feces are

Answer 77

undigested food material and other waste products

Question 78

the rectum is

Answer 78

the final portion of the large intestine/ colon

Question 79

How is digestive waste removed from the body (2)

Answer 79

- feces are stored in rectum until they can be eliminated. - 2 rectal sphincters, 1 voluntary & other involuntary, regulate the opening of the anus

Question 80

Bacteria in colon produce .... (2)

Answer 80

important vitamins, including vitamin K & some B vitamins - these vitamins are absorbed into the bloodstream from the colon.

Question 81

Discomfort in digestive system can be caused by ....

Answer 81

eating too much, eating too quickly, or eating an inappropriate combination of foods

Question 82

Gas in the digestive system is a result of... (2)

Answer 82

swallowed air or the breakdown of undigested food in colon - Gas is made of odourless CO2, oxygen, hydrogen, & nitrogen --> when it's passed through the rectum, it also includes small amounts of sulphur produced by bacteria there & the gas may smell unpleasant

Question 83

Persistent or intensive discomfort in digestive system may be caused by....

Answer 83

inflammation, infection, malabsorption (difficulty in the digestion or absorption of nutrients from food), or another disorder

Question 84

Endoscopy (3)

Answer 84

is when a narrow tube is inserted into the throat & passed into the esophagus, stomach, & upper intestine - a small camera in the narrow tube enables the doctor to see the internal structures & to identify abnormalities - sometimes the tube has tiny scissors that are used to cut a small piece of tissue for viewing under a microscope (biopsy)

Question 85

A biopsy is (2)

Answer 85

Google: a procedure to remove a piece of tissue or a sample of cells from your body so that it can be tested in a laboratory. - A biopsy is used to determine if the cells are normal & can also identify presence of Helicobacter pylori bacteria, which burrow into the stomach wall & cause inflammation.

Question 86

Colonoscopy is (3)

Answer 86

when a thin, lighted tube with an attached camera is inserted through the rectum - used to diagnose intestinal disorders, as it allows doctors to see further along the intestines - if unusual growth is detected, the doctor may opt for a biopsy. --> if the biopsy indicates that the cells are abnormal or cancerous, it's sometimes possible to surgically remove those cells during the diagnostic procedure

Question 87

A less invasive diagnostic tool to examine digestive tract is... (2)

Answer 87

a procedure where the patient swallows a pill that contains a camera. Called "pill cam" or capsule endoscope --> the pill proceeds through the intestines, it takes pics of the structures. --> the pill is later eliminated in feces/

Question 88

Sum table on 295

Question 89

The leading cause of death in Canadian adult men & women is _____________________

Answer 89

Cardiovascular Disease

Question 90

Cardiovascular Disease is (2)

Answer 90

any disease that affects the heart & blood vessels. - research shows that certain cardiovascular diseases cause changes to the lining of arteries, reducing the blood flow rate. --> when flow of blood in arteries is restricted, the cells cannot always obtain necessary nutrients efficiently & cell function is reduced or ceases.

Question 91

"Laughter is the best medicine" (4)

Answer 91

- stressful experiences can decrease the diameter of arteries, causing cardiovascular diseases - Scientists have investigated changes in the rate of blood flow in arteries before & after exposure to laughing. Also investigated the effects to joyful music. --> in both types of experiments, results showed an increase in arterial diameter - Essentially, including positive & joyful experiences in our daily lives could be good medicine

Question 92

All the cells in an animal need to ___________________, _______________, & ______________________ (3)

Answer 92

gain nutrients, exchange gases, remove waste products - some aquatic animals that have bodies only a few cells thick, transport materials across their cell membrane to & from their environment - larger animals use an internal transport system to bring resources close enough to all cells for exchange of materials to occur - Most animals have a CIRCULATORY SYSTEM that transports oxygen & carbon dioxide, distributes nutrients to cells, & removes cellular wastes.

Question 93

Your cells need a constant supply of ___________ & ___________

Answer 93

nutrients, oxygen

Question 94

The 3 primary components of the circulatory system are the __________, ___________, & _________________

Answer 94

blood, heart, blood vessels - blood is pumped by the heart into the blood vessels

Question 95

Open Circulatory Systems (3)

Answer 95

Many invertebrates have open circulatory system in which blood is NOT entirely contained within blood vessels. - Ex, grasshoppers, molluscs, arthropods - in these systems, a tubular heart (like a sline) pumps blood through vessels that open into spongy chambers called sinuses --> from sinuses, the blood bathes the body tissues, then collects in another set of sinuses & makes its way back to the heart!!!!

Question 96

Closed Circulatory Systems (4)

Answer 96

- Earthworms, squids, octopuses, & vertebrates all have closed circulatory systems. - in this system, blood remains contained entirely within blood vessels that extend throughout the body - nutrients, oxygen, & waste move in and out through the thin walls of the smallest blood vessels

Question 97

In which system is blood circulated more efficiently : open or closed circulated system

Answer 97

- Blood is circulated more efficiently in a closed circulatory system that an open circulatory system. --> cuz blood is completely contained within blood vessels can be pumped under higher pressure than blood in open-ended vessels.

Question 98

Cardiovascular System (4)

Answer 98

- The closed circulatory system in humans & other vertebrates is sometimes called the cardiovascular system. (Greek kardia = heart, Latin vas= vessel) - our system has a network of 100, 000 km blood vessels (would encircle Earth two & half times) - supplies oxygen & nutrients, removes CO2 & other wastes in trillions of cells - it is very efficient --> normally it takes 1 minute for blood to make a complete circuit through ur body. --> increased activity like running, causes ur blood to circulate more quickly, keeping ur cells supplies with oxygen & nutrients.

Question 99

Blood is (4)

Answer 99

a highly specialized connective tissue--> part fluid (plasma) , part cellular (red & white blood cells, & platelets - we have 4-6L of blood - it transports oxygen, water, nutrients, and other chemicals to ur cells, and transports waste from tissues to areas where they can be removed - it helps regulate body temp, fight infections, & heal wounds

Question 100

Plasma (5)

Answer 100

= 55% of blood volume - straw-colored liquid - it's 90% water, which helps control body temp (google: When the body temperature increases, water from the plasma comes out as sweat from sweat glands. This reduces the body temperature) - it is 10% is proteins, dissolved nutrients, & wastes like CO2 - Plasma proteins transport fatty acids & vitamins, & fight viral & bacterial infections

Question 101

Red Blood Cells are (6)

Answer 101

are cells that carry oxygen from the lungs to all tissues of the body - a cellular component of blood - remaining 45% of blood volume is MOSTLY red blood cells - one cubic mm of blood contains 5 million red blood cells - 1 red blood cell has about 250 million hemoglobin molecules. --> Oxygen molecules bind to iron part of hemoglobin molecule, giving blood the crimson colour - once oxygen is released, red blood cells transport CO2 to lungs

Question 102

Hemoglobin is

Answer 102

a protein that binds oxygen in the lungs & releases it throughout the body

Question 103

Where are red blood cells reproduced?

Answer 103

- in bone marrow at the rate of 2 million per second in a healthy adult

Question 104

Red blood cell Structure (5)

Answer 104

- when they mature, they lose their nuclei & mitochondria --> gives them their shape: flat disk curving inwards in middle on top & bottom --> shape increases surface area for oxygen transfer compared to a spherical shape with same volume --> shape gives them flexibility so that they can pass through blood vessels of different shapes & sizes - Since adult red blood cells has no nucleus, it cannot replace its proteins, grow, or divide. - have a lifespan of a red blood cells of 100-120 days --> as they age, they become fragile & eventually break down. --> the iron from broken-down red blood cells is recycled in bone marrow where it becomes part of new blood cells

Question 105

White Blood Cells are (5)

Answer 105

cells that protect against infection, fight parasites, & attack bacteria. - a cellular component of blood - they do not have to stay with the blood vessels--> can move through vessel walls to attack foreign organisms - usually, there are 4,000-11,000 white blood cells in 1 cubic mm of blood. -->dramatically increased when body has an infection - Sometimes u notice pus forming at cuts. the pus= white blood cells + dead bacteria

Question 106

Similarity & difference between red & white blood cells

Answer 106

- both are produced in bone marrow - white blood cells keep their nuclei (undergo mitosis) & can live for years - White blood cells are the ones responsible for Leukemia (blood cancer) as they are the only cells that have nucleus

Question 107

Platelets are (4)

Answer 107

cell fragment that originate when the cytoplasm of certain bone marrow cell divide --> the fragments, each enclosed in a cell membrane, break off & enter the blood - a cellular component of blood - 1 cubic mm of blood has 250,000-500,000 platelets - the blood-clotting that stops blood flow upon injury is due to platelets--> platelets stick to the blood vessel damage site. --> they break apart & release substances called clotting factors. --> this makes nearby platelets sticky & activates a series of reaction among other clotting factors in the plasma, creating fibrin. --> within a few minutes this network of threads and cells builds up, eventually forming a patch that stretches over the torn tissue, forming a scab. This will protect the while new tissue grows.

Question 108

Fibrin is

Answer 108

a stand-like protein that threads trap red blood cells & platelets.

Question 109

How come some people's wounds don't clot normally with the use of platelets? (2)

Answer 109

- some people have hemophilia, in which they do not have the necessary protein to form blood clots - their wounds bleed for longer than normal periods & they may need medical assistance to stop the flow.

Question 110

Blood Vessels are

Answer 110

tubes that form a pipeline within the body. - Its walls are made up of smooth muscle tissue that regulates the diameter of the blood vessel, and connective tissue that enables the blood vessel to expand & contract as blood flows through it. - Epithelial tissue lines the wall of all blood vessels. - there are 3 types of bloods vessels: Arteries, Capillaries, & Veins

Question 111

Blood Vessels: Arteries are (5)

Answer 111

large blood vessels that carry blood from the heart to the tissues. - the walls of arteries are made up of epithelial tissue wrapped in layers of smooth muscle & connective tissue - the blood in arteries is under pressure due to the heart's pumping action. --> the pressure ensures that the blood flows in one direction, towards the tissues. - Arteries have thick walls because they need to withstand high pressure generated by the heart - Further from the heart, the arteries branch into smaller & smaller vessels. --> the narrowest arteries (arterioles) flow into capillaries.

Question 112

Arterioles are

Answer 112

the narrowest arteries that flow into capillaries

Question 113

Blood Vessels: Capillaries are (4)

Answer 113

microscopic blood vessels with a high surface area resembling a network of tiny tubes - Capillaries are used to by the circulatory system to have close contact with all the cells in the body to distribute nutrients & oxygen - some capillaries are so narrow that only a few cells can travel through them at a time - The walls of capillaries consist of a very thin layer of epithelial tissue encased in a moist membrane --> enables nutrients & oxygen to pass out of the blood, & waste products to pass into the blood.

Question 114

Blood Vessels: Veins are (5)

Answer 114

blood vessels that bring blood from the capillaries back to the heart. - the walls of veins, like arteries, consist of epithelial tissue surrounded by smooth muscle & connective tissue --> however muscle layer in veins are thinner than arteries cuz the blood in veins is under very little pressure - the main force that pushed blood though the veins comes from the skeletal muscle tissue where many veins are located. --> contracting these muscles squeezes the veins & forces blood through them. --> most veins contain flaps of tissue (valves) that restrict blood flow to the heart only. - small veins merge into larger ones

Question 115

How do nutrients pass from the blood vessels into the individual cells of ur body?

Answer 115

Process of diffusion: molecules move across a membrane from an area of higher concentration to an area of lower concentration

Question 116

The Diffusion Gradient is (2)

Answer 116

the gradual change in the concentration of solutes in a solutions as a function of the distance through a solution. - other words: if the blood in a capillary has a higher concentration of oxygen than the fluid next to it, the oxygen moves spontaneously into the fluid by diffusion

Question 117

Where does the process of molecules diffusing out of the blood into the cells occur? (4)

Answer 117

the capillaries - Capillaries are in close contact with body cells. --> no further than 10 micrometers from a capillary & the blood in it. - critical to the main function of circulatory system: distribution of oxygen & nutrients, & removal of waste products

Question 118

Can molecules in the capillaries enter cells directly?

Answer 118

Nope --> body cells are surrounded by fluid, so molecules must enter fluid first, and then the cells.

Question 119

The exchange of small molecules between capillary & the fluid.

Answer 119

- some small molecules (O2 or CO2), diffuse across cell membranes or pass through gaps between the epithelial cells of the capillary wall into the fluid. Ex. O2 diffuses from blood into fluid, & CO2 diffuses fluid into the blood.

Question 120

The exchange of large molecules between capillaries & the fluid.

Answer 120

- Large molecules are sent into the fluid with the help of other transport processes like blood pressure. - blood pressure = the force blood exerts against artery walls. --> drives blood through the arteries, into the capillaries, & through the capillary walls. - once in the fluid, needed molecules move into the cells by diffusion - cell wastes move out of the cells into the fluid & eventually into the blood.

Question 121

The lymphatic system is

Answer 121

a network of vessels, nodes (connecting points), & organs that collects the fluid that leaves capillaries, "screens" it for microorganism, & returns it to the circulatory system. --> when blood passes through capillaries, some of its components move through capillary walls & into the fluid between cells. --> Daily, 3-4L of fluid leave the blood to surround ur cells.

Question 122

What is fluid collected by the lymphatic vessels called?

Answer 122

lymph --> it's a clear, watery fluid made up of protein molecules, salt, glucose, & other substances - it's collected in a system of lymph vessels, where valves prevent lymph from flowing back towards capillaries - the combination of muscle contractions squeezing the vessels & the one-way valves helps fluid move through the lymphatic system --> lymph is drained into the circulatory system near heart.

Question 123

What would happen if lymphatic system did not drain lymph form the tissues

Answer 123

the lymph would accumulate, causing swelling called edema

Question 124

What is the spleen?

Answer 124

An organ that helps remove old or damaged blood cells, stores platelets, & helps control the amount of blood & blood cells that circulate through the body - located in the upper left part of the abdomen under the ribcage.

Question 125

Some lymph vessels run alongside the small intestine to....

Answer 125

pick up fats & fat-soluble vitamins from the digestive tract & transports them into the bloodstream

Question 126

The lymphatic system also helps improve ____________

Answer 126

immunity 1)White blood cells mature in an organ called the thymus 2)Hundreds of lymph nodes (= small, bean-shaped enlargements) are scattered along lymph vessels throughout the body. --> filter out harmful micro-organisms & abnormal cells.

Question 127

When & who invented the stethoscope? (4)

Answer 127

- In 1816, French doctor Rene Laennec (with accents) wanted to better diagnose his patients by hearing their heartbeat & other chest sounds. - He rmred that placing wood at ur ear, the sound was amplified, so he rolled a piece of paper (which is made of wood), placed on end on the patient's chest and the other at his ear, and the sound was much clearer. - He invented the first stethoscope, which was later refined to what we have today - He wasn't exactly correct as its not the wood that amplifies sound but the hollow tube that focuses & reflects the sounds

Question 128

Anatomy of the Heart (5)

Answer 128

- size of clenched fist, its a hollow organ located between lungs & is almost entirely muscle. - structure of heart enables it to pump oxygen-poor blood to lungs & oxygen-rich to body. - the pericardium encloses the heart. - the mammal heart has 4 chambers: the right atrium, the right ventricle, the left atrium, & the left ventricle - valves in the heart prevent blood from flowing backwards

Question 129

Cardiac Cycle is

Answer 129

the entire process of pumping blood out and filling the heart with blood - heart contracts=blood pumped out, heart relaxes= blood enters heart - in average person, takes approximately 0.8 seconds

Question 130

The Pericardium is

Answer 130

a protective sac that enclosed the heart. - its filled with fluid that lubricates the surfaces of the heart and the roots of the major blood vessels

Question 131

Artia are (3)

Answer 131

(singular, atrium) the 2 upper heart chambers which receive blood returning to heart - since they only pump blood the short distance to the ventricles, they have fairly thin walls

Question 132

Ventricles are (2)

Answer 132

the 2 lower heart chambers, which pump blood out of the heart to the body - have thick muscular walls that enable them to pump blood throughout the body.

Question 133

Types of Heart Valves

Answer 133

1) valves between artia & ventricles= atrioventricular valves 2) valve between right ventricle & pulmonary artery= pulmonary valve (pulmonary comes from latin word for lung) 3) valve between left ventricle & aorta= aortic valve (aortic comes from greek word for "to lift")

Question 134

What causes the "lub dub" sound of the heart? (2)

Answer 134

- with each heartbeat, the valves open, allowing blood to flow through. --> Then they close preventing blood from flowing back - When the valves close, they cause the familiar heart sound of "lub dub". --> the "lub" sound is the atrioventricular valves closing, while the "dub" sound happens when the pulmonary & aortic valves close

Question 135

What are the 2 circuits of blood flow

Answer 135

- though it's 1 organ, the heart acts like 2 pumps - 1 pump pushes blood into lungs and the pathway is called the pulmonary circuit - other pump pushes blood to rest of the body and the pathway is called the systematic circuit - this double pathway ensures that the oxygen-rich blood is constantly delivered to cells

Question 136

Pulmonary Circuit

Answer 136

- In this circuit, blood travels from the right side of ur heart through the pulmonary arteries to ur lungs - in the lungs, blood picks up oxygen & releases CO2, which u then exhale - The pulmonary veins return the oxygen-rich blood to the left side of the heart - Most arteries in ur body carry oxygen-rich blood & most veins carry oxygen-depleted blood --> however, it's the opposite in pulmonary circuit. --> pulmonary arteries carry oxygen-depleted blood to lungs & pulmonary veins carry oxygen-rich blood from lungs to heart

Question 137

Systematic Circuit (6)

Answer 137

In this circuit, oxygen-rich blood from lungs gathers in the left atrium & is then pumped to the left ventricle - the blood is then pumped through the aorta, the artery that supplies oxygen-rich blood to all the systems of the body. - From the aorta, oxygen-rich blood flows through the branching arteries to the capillaries. --> oxygen & other nutrients diffuse out of blood, & CO2 & other wastes diffuse in - The now oxygen-depleted blood returns to right atrium through vena cava veins: superior vena cava & inferior vena cava (vena latin for vein & cava latin for cave or hollow) - blood is pumped into right ventricle, which pumps it to the lungs through pulmonary arteries - After being replenished with oxygen in the lungs, blood returns to heart through pulmonary veins & gathers in the left atrium.

Question 138

Coronary Arteries are (3)

Answer 138

a pair of arteries branching from the aorta that cover the surface of the heart like a crown and is used to supply the heart muscle cells with nutrients. - they exist cuz heart recieves very little oxygen & nutrients for its cells from blood it pumps through its chambers - In Latin, "coronary"= crowned

Question 139

The teenage heart beats over...

Answer 139

100, 000 times daily, on average 60-100 times per minute

Question 140

The rate at which ur heart pumps & the amount of blood that it pumps are affected by factors like...

Answer 140

age, fitness, & emotions - Ex. Athletes may have heart rate lower than 60 (Exercise strengthens the heart muscle, enabling it to pump a greater volume of blood with each heartbeat. More oxygen gets delivered to the muscles, so the heart needs to beat fewer times than it would in a less-fit person while at rest) - Ex. Children & babies usually have heart rates over 100

Question 141

A Pacemaker is

Answer 141

a specific region of heart muscle that sets the rate at which ur heart contracts - located in wall of right atrium - generates electrical impulses that rapidly spread over walls of both atria, making them contract --> impulses then spread to heart region called the atrioventricular (AV) node. --> from there, the electrical impulses spread to ventricles, causing them to contract, which sends blood to rest of the body. - it ensure that the heart beats in rhythmic cycle: first atria contract, forcing blood to ventricles, which are relaxed. Then ventricles contract, forcing blood to arteries, while atria are relaxed. --> repeats at rate of 1 second during rest

Question 142

How is the pacemaker controlled?

Answer 142

-controlled by both nervous system & endocrine system (which creates hormones) - 2 sets of opposing nerves control the pacemaker by speeding it up & by slowing it down - Hormones, secreted into blood, also control the pacemaker. Ex. hormone epinephrine AKA adrenaline, increases the heart rate when body is under stressed.

Question 143

A Sphygmomanometer is

Answer 143

a pressure cuff used to measure blood pressure - made in mm of mercury (mm Hg), a standard unit of liquid pressure - the measurement is represented by 2 numbers separated with a slash like 120/70. - the first # is called systolic pressure = highest recorded pressure in an artery when ventricles contract - second # is Diastolic pressure= lowest recorded pressure in an artery during relaxation phase of the heartbeat

Question 144

What factors does blood pressure depend on?

Answer 144

- depends on 2 factors 1) Cardiac Output = the amount of blood is pumped by the heart each minute. Ex. if the volume of blood pumped through an artery increases, the blood pressure would also increase 2) Resistance of Arteries AKA Arterial Resistance --> related to elasticity in the arteries. Ex. If the arteries do not expand easily & resist the flow of blood, the pressure on the arterial walls increases

Question 145

Blood pressure varies according to an individual's....

Answer 145

height, weight, fitness level, as well as time of day, physical activity, hydration, & other factors. - With age, blood pressure can increase - smoking or high fat diets can increase blood pressure by causing arteries to become less elastic

Question 146

Blood pressure in healthy young adults

Answer 146

- in healthy young adults, it varies between 110-130 over 70-90 with an average of 120/80 - A blood pressure consistently about 140/90 is considered high

Question 147

What is an Exercise Stress Test?

Answer 147

- test used to monitor the structure & function of circulatory system components including the heart, blood, & blood vessels. - patient performs exercise on a stationary bike or treadmill while hooked to an electrocardiograph that measures the electrical activity of the heart. --> heart rate, respiratory rates, blood pressure, & how tired the patients feels is also monitored - it helps diagnose coronary artery disease, determine a safe level of exercise, & predict risk of severe conditions like heart attacks.

Question 148

Plaque is (3)

Answer 148

a patchwork of cholesterol, calcium, & fat deposits sticking to the interior walls of arteries. - plaque builds up throughout a person's life --> thus, baby arteries have smooth clear surfaces - Significant buildup of plaque can ultimately lead to cardiovascular disease.

Question 149

Atherosclerosis is (5)

Answer 149

a narrowing of the arteries resulting from plague building up inside the artery wall. - as pathways narrow bp increases - Sometimes the narrowing completely blocks blood flow, and if such blockage were to happen in one of the coronary arteries, the heart becomes deprived of O2 & nutrients. - partial blockage cases= occasional chest pains called angina pectoris. --> treatment= angioplasty, where a small metal mesh tube is placed in artery, & it expands to artery from closing up - severe blockage=blood clot could clos up artery, causing heart attack

Question 150

A Heart Attack is (5)

Answer 150

when the blood supply to the heart tissue is slowed or stopped usually due to narrowing coronary arteries cuz of atherosclerosis. - During a heart attack, the heart usually doesn't stop beating. - symptoms include chest pain & upper body pain, that can be accompanied with shortness of breath & nausea - if treatment is immediate, some of the heart muscle will die & be replaced by scar tissue. - very rare in teens

Question 151

Arteriosclerosis is

Answer 151

an advanced stage of plaque buildup, which occurs when the deposits on the artery wall harden - Arteries are flexible & can expand & contract, helping control bp --> with arteriosclerosis, the arteries lose their ability to stretch --> this increases bp & the chance for blood clots to form within the blood vessels - treatment includes heart bypass surgery, where a surgeon will take a vein or artery from another body part & use it to makes a detour around the blocked part of the coronary artery

Question 152

Sudden Cardiac Arrest is (4)

Answer 152

when the heart suddenly stops functioning, as from drowning, electrocution, trauma, or choking - most common cause is coronary heart disease, where the coronary arteries become blocked --> coronary blockages causes the heart to beat irregularly so that blood isn't pumped efficiently & in a regular rhythm. - if the heart rhythm is not reset immediately, like by a cardiac defibrillator, death will be within minutes

Question 153

Arrhythmia is (4)

Answer 153

a condition in which the heart beats irregularly, too quickly, or too slowly - Most arrhythmia arises from problems with the electrical activity of the heart - symptoms include dizziness, chest pain, & shortness of breath - treatment to restore normal heartbeat includes implanting an artificial pacemaker or a small defibrillator under the skin of chest of abdomen

Question 154

Hypertension is (6)

Answer 154

AKA high bp is when blood pressure is 140/90 or higher for an extended period of time --> which damages the heart & blood vessels --> the heart must work harder to pump blood throughout the body, & over time, the heart muscles expand. --> if these muscles expand too much, they become weakened & can no longer push blood throughout the body. - hypertension also exerts greater pressure on artery walls, causing small tears. --> these tears can speed up atherosclerosis, which further increases bp - teens can have high bp via genetic factors, excess body weight, diet, or lack of exercise.

Question 155

Heart Failure is (4)

Answer 155

a condition in which the heart can't pump blood efficiently, cuz it can't fill with enough blood or can't send blood out to the body with enough force - it's a common condition, affecting both children & adults - if diagnosed early, people with heart failure can live longer & lead more active lives by improving their lifestyle & following treatment plans - in most severe cases, heart transplant may be necessary

Question 156

An aneurysm is (5)

Answer 156

a bulge in the wall of an artery. - can be caused by injuries , genetic conditions, or disease - as blood rushes through the artery, it further weakens the bulging wall & may burst through, causing serious internal bleeding - can occur in any artery but usually in aorta branches. - can be detected using Magnetic Resonance Imaging (MRI), a non-invasive imaging technology that produces 3d views of organs & tissues

Question 157

A stroke is

Answer 157

when a blood clot forms in an artery going to the brain. - tissues downstream from the blockage can die from lack of O2. - effects of strokes include partial paralysis, loss of speech, memory loss, & sometimes death. --> depend partially on location of brain where blockage occurred.

Question 158

List 5 controllable choices that promote Cardiovascular Health

Answer 158

- Eat a healthy diet - Maintain a Healthy Weight - Exercise Regularly - Avoid Smoking & Second-hand Smoke - Get Regular Health Checkups

Question 159

5 controllable choices that promote Cardiovascular Health: Eat a healthy diet

Answer 159

- Good choices for the heart include foods that are high in fibre & low in salt and LDL cholesterol. - Low-Density Lipoprotein (LDL) is found in foods high in saturated or trans fat like beef, butter, cheese, ice cream, deep-fried food, bakery food, margarines, & packaged snack foods

Question 160

Cholesterol is (5)

Answer 160

a fat that is a part of ur cell membranes & is used to synthesize hormones, bile, & vitamin D - its made in liver, carried to tissue by blood. - Cholesterol is transported by 2 types of lipoproteins= carriers made of fat & proteins - High-Density Lipoprotein (HDL) is called "good cholesterol" cuz it helps remove excess cholesterol in tissues & arteries - Low-Density Lipoprotein (LDL) is called "bad cholesterol" cuz it becomes part of the plaque in the arteries

Question 161

5 controllable choices that promote Cardiovascular Health: Maintain a healthy Weight (2)

Answer 161

- avoid fat diets - consult a health practitioner for diet plans and a counsellors for coping strategies

Question 162

5 controllable choices that promote Cardiovascular Health: Exercise Regularly (2)

Answer 162

- regular exercise reduces chances of condition that strain heart like high bp, high cholesterol, & diabetes - Aim for 40-60 minutes of moderately intense activities most days of week

Question 163

5 controllable choices that promote Cardiovascular Health: Avoid Smoking & Second-hand Smoke (3)

Answer 163

- Tobacco smoke contains thousands of chemicals that can damage the tissues of ur heart & blood vessels 1)Nicotine= a chemical found in tobacco smoke, narrows blood vessels & increases heart rate & bp 2) the carbon monoxide in cigarette smoke replaces some oxygen in blood, forcing ur heart to work harder to supply enough oxygen

Question 164

5 controllable choices that promote Cardiovascular Health: Get Regular Health Checkups (1)

Answer 164

- health practitioners can check ur bp, heart sounds, pulse rates, weight, & other indicators of ur health & track them from year to year --> can make suggestions early on to avoid issues later in life

Question 165

what cancer is currently the leading cause of cancer deaths globally?

Answer 165

lung cancer

Question 166

Why are traditional means of detecting cancer not the best?

Answer 166

- X-rays & CT scans only detect the cancer once it is well developed - its really hard to detect cancer in early stages with this tech

Question 167

"Sniffing out" cancer in early stages (5)

Answer 167

- over 3 weeks, a research team trained dogs to detect cancer by exposing them to cancer patients breath - healthy patients were used as experimental control - it had an accuracy between 88-97% - scientists found out that lung cancer cells produced unique chemicals that form gases that are expelled from the patients' body in the breath which dogs could pick up on - this research can lead to developing tech to screen lung cancer simply using exhaled breath.

Question 168

Cellular respiration is.... (5)

Answer 168

a process that produces energy needed to fuel all cell activities - it occurs in mitochondria. - cells must have a constant O2 supply, & must constantly dispose of CO2 - if O2 isnt enough, energy isn't produced efficiently, & cells ae harmed - In order for cells to obtain enough O2, large volume of air must enter body --> about 21% of air= O2

Question 169

In animals with lungs, the transfer of gases from environment 2 the body & 2 the cells occurs in 3 phases: ____________, __________________, ______________________

Answer 169

breathing, transporting of gases, & exchange of gases in cells

Question 170

The respiratory surface is (2)

Answer 170

a very special membrane that gas exchange usually occurs in for multicellular organisms - Although animals live in a wide variety of environments, the process of diffusion via the respiratory surface governs the function of their respiratory surface.

Question 171

A respiratory surface has certain characteristics to ensure that diffusion occurs efficiently which are..... (3)

Answer 171

1) A respiratory surface is a very thin & moist membrane that is permeable to the gases being diffused 2) The surface area of the membrane is large so as to maximize diffusion 3) A diffusion gradient must be maintained cuz diffusion moves gases from higher concentration to lower concentration --> other words: there must be a difference in concentrations of oxygen & CO2 on either side of the membrane surface. --> In most organisms, the circulatory system serves to transport gases to & from the membrane so that appropriate gas concentrations can be maintained

Question 172

Can animals use their entire body surface as a respiratory surface? (3)

Answer 172

- Yes, ex. earthworms - Animals that breath through their skin are usually small or have flat bodies that give a high ratio of respiratory surface to body volume - Animals that breathe through their skin live in damp places or in water to keep their body surface moist.

Question 173

Gas Exchange in Aquatic Animals (4)

Answer 173

- they live in water, thus respiratory surface is always moist - cuz source of useful gas is dissolved in water, an appropriate volume of water must come in close contact with thin respiratory membranes & yet not damage them --> hence, most have gills= folds in body surface specialized for gas exchange. Are extensions of body surface - gill design enables water to flows that gases diffuse from water & across respiratory membranes --> O2 diffuses directly into capillaries & CO2 diffuses out of capillaries & into the environment --> capillaries transport gases to and from gills to body cells

Question 174

Advantages & disadvantages that terrestrial animals that exchange gases by breathing air have compared to aquatic animals that exchange gases in water.

Answer 174

ADVANTAGES 1) There is a higher concentration of oxygen in air than water 2) Air is both lighter & easier to move than water - terrestrial animals need to spend less energy than aquatic ones to exchange gases across respiratory surface DISADVANTAGES 1) terrestrial animals lose moisture to their environment - most terrestrial animals have evolved internal respiratory surfaces like tracheal systems & lungs to minimize loss of moisture.

Question 175

A tracheal system is

Answer 175

a system of tubes that extend through their bodies in many insects - air enters & leaves system though openings in body surface - larger tubes=tracheae branch into smaller & smaller tubes=tracheoles which extend to nearly every cell in the insect's body - gas exchange occurs along the moist membranes at the tips of the tracheoles

Question 176

Do insects need a circulatory system to exchange gases? (4)

Answer 176

No - small insects can receive enough O2, & get rid of enough CO2 through diffusion across their membrane - Larger insects pump in more air through rhythmic body movements that compress & expand the air - their flight muscles help to rapidly pump air through tracheal systems --> thus insects consume much more O2 when they fly

Question 177

Lungs are (4)

Answer 177

internal, thin-walled sacs with large surface area that is the site of gas exchange in birds, mammals, reptiles, & some amphibians - Human lungs: right=3 lobes, left= 2 lobes cuz of heart - in lungs O2 diffuses into blood & is transported through blood vessels to body cells. - CO2 diffuses out of blood, enters lungs, & moved out of body through breathing - Aquatic reptile & mammals that breath air must hold their breath under water

Question 178

The structures of the human respiratory system in order include....

Answer 178

the mouth, the nose (same level in order), pharynx, larynx, trachea, & lungs, - work together to move gases in & out of body

Question 179

Gas Journey to lungs: step 1 (3)

Answer 179

As u inhale, air enters respiratory system. - many air impurities in air like dirt & bacteria, are filtered by hair & mucus in ur nose. - Air is warmed & moisture is added

Question 180

Gas Journey to lungs: step 2 (2)

Answer 180

Air passes into pharynx, where passageways for air & food cross. - pharynx is always open unless when u eat (rmr epiglottis)

Question 181

Gas Journey to lungs: step 3 (3)

Answer 181

- From pharynx, air goes to larynx (voice box)--> the 2 vocal cords in larynx vibrate, producing sound - then air enters trachea (windpipe) --> C-shaped rings of cartilage maintain tubular shape of trachea. - the trachea splits into 2 bronchi (singular= bronchus), which are air tubes that connect the trachea to lungs

Question 182

Gas Journey to lungs: step 4 (3)

Answer 182

- in each lung, the bronchus repeatedly branches into finer & finer tubes = bronchioles - bronchi & bronchioles are surrounded by smooth muscle. --> as muscles contract or relax, they control size of airways

Question 183

Gas Journey to lungs: step 5 (2)

Answer 183

- Each bronchiole ends in grapelike clusters of tiny air sacs called alveoli (singular=alveolus) - ur cells contains millions of these tiny air sacs, which provide a very larger surface area for gas exchange

Question 184

why are alveoli suitable for gas exchange? (3)

Answer 184

1) they have thin walls 2) great surface area 3) have direct contact with capillaries

Question 185

Respiratory System Lining (3)

Answer 185

- from ur nose & mouth all the way to ur lungs, is lined with moist epithelial tissue. - In trachea & bronchi, epithelial cells are lined covered in cilia & , a fine layer of mucus. --> the mucus traps foreign particles & removes them from the air, purifying it. --> the cilia then sweep mucus-trapped particles up towards pharynx where they can be coughed out or swallowed.

Question 186

Breathing is (3)

Answer 186

AKA ventilation the process of moving air into & out of ur lungs - on average u breathe about 15 times/min or more than 21,000 breaths daily

Question 187

What is the size of ur lungs? (3)

Answer 187

about size of football each - together have a total capacity of 6L but u only use 0.6 L of the volume in normal breath. - when exercising vigorously, u can use up to about 20x the oxygen u use at rest

Question 188

The process of ventilation is a largely a __________ process.

Answer 188

passive - meaning the process works without ur attention & without using extra energy

Question 189

what 2 structures change the volume & thus the air pressure of the chest cavity during process of breathing? (3)

Answer 189

Diaphragm & Rib Muscles - Inhale= diaphragm & rib muscles contract.--> inhalation expands chest cavity, increasing volume of lungs, resulting in reduced air pressure within the alveoli. --> since air moves from high pressure areas to low pressure areas, air rushes in through ur nose or mouth & fills the alveoli - When diaphragm & rib muscles relax, ur lung volume decreases, causing higher air pressure in the alveoli. Air rushes from ur lungs out through ur nose or mouth as u exhale

Question 190

Gas Exchange in Lungs (5)

Answer 190

- the inner surface of each alveolus is lined with a layer moist epithelial cells - O2 inhaled dissolves in the film of moisture on these epithelial cells - The oxygen then diffuses into a web of capillaries surrounded each alveolus & enters red blood cells, binding to hemoglobin --> hemoglobin increases the efficiency of gas exchange by creating diffusion gradient. Other words, when the hemoglobin in a red blood cell binds to O2, it removes oxygen from the plasma. - oxygen then keeps on diffusing from the alveolus into the plasma cuz the O2 concentration is lower in the alveolus - By binding oxygen, the hemoglobin actually increases the blood's ability to transport oxygen about 60x

Question 191

Transporting O2 & CO2

Answer 191

- ur cells access O2 they need from nearby blood vessels - As cellular respiration produces energy, CO2 is produced as a by-product of that process - CO2 diffuses the opposite way to oxygen, from the capillaries across the epithelial cells & into the alveoli - The CO2 is carried away from the cells & deposited in the lungs --> then CO2 is expelled back up the trachea, through the nose or mouth, & into the environment

Question 192

Breathing is controlled by the________________

Answer 192

medulla oblongata--> a part of the brain located near the top of the spinal cord --> it sends nerve signals to the diaphragm & rib muscles, causing them to contract & relax

Question 193

What controls the breathing rate?

Answer 193

- surprisingly, it is usually the level of CO2 that controls breathing rate --> When CO2 dissolves in a solution containing water, it forms Carbonic acid (H2CO3) - CO2 diffuses through a capillary wall, most of it dissolves in the plasma - Ex. when u exercise heavily, cell metabolism increases carbon dioxide output. This causes more CO2 to dissolve in the plasma. The increased CO2 dissolved in the plasma slightly lowers the pH of the plasma (more H+ ions). A drop in pH level causes the brain to send nerve impulses that increase breathing rate. As a result, more CO2 is exhaled, & the pH returns to normal, a state called homeostasis

Question 194

Homeostasis is

Answer 194

the state of internal stability maintained by the body

Question 195

__________________ is one of the best things u can do for ur respiratory health. (4)

Answer 195

Regular exercise - helps strengthen all body muscles including heart & diaphragm. - vigorous activities like swimming & skiing increase ur lung capacity & help ur body use O2 more effectively. - Inactivity & a sedentary lifestyle decrease ur ability to exchange O2 for CO2

Question 196

A sedentary lifestyle is

Answer 196

one that lacks enough vigorous physical activity.

Question 197

The structures & function of the respiratory system can be altered by..... (2)

Answer 197

disease or exposure to viruses or environmental pollutants - Ex. environmental pollutants can trigger respiratory allergies like hay & fever, & cause the tissues in the airways to swell

Question 198

Common Cold & Respiratory System

Answer 198

- common cold is a group of symptoms like coughing, sneezing, & a sore throat - can be caused by number of viruses that pass through the protective lining of nose & throat - sometimes accompanied by sinusitis

Question 199

Sinusitis is (4)

Answer 199

a condition caused by viruses or bacteria in which the sinuses become swollen & irritated - Sinuses=moist air spaces around the nose --> when they become inflamed, u may notice change in voice - Includes a stuffy or runny nose, pain or swelling around eyes & cheekbones, & a feeling of pressure in the head - Dry air, lack of sleep, allergies, stress, second-hand smoke, & not eating properly all lower resistance to cold & sinusitis

Question 200

Influenza is (5)

Answer 200

AKA flu is a common viral infection of the upper respiratory system - it's spread by airborne droplets & contact with contaminated objects - can cause more serious respiratory illnesses, especially in elderly, infants, & people with heart & lung disease - Ex. it can develop into pneumonia

Question 201

Pneumonia is

Answer 201

a serious infection of the lungs - the alveoli in the lungs fill with fluid, which prevents O2 from reaching the blood - can be caused by a variety of viruses, bacteria, fungi, & parasites

Question 202

Asthma is (5)

Answer 202

a chronic disorder of the respiratory system in which airways become narrowed. - smooth muscles surrounding the bronchi & bronchioles contract, narrowing the airway, making breathing very difficult --> makes it fatal - can be caused by exposure to airborne pollutants, cold air, cigarette smoke, some drugs, & respiratory infections - usually, a doctor may prescribe use of puffer to improve breathing --> it administers a regulated amount of bronchodilator= drug that causes narrow airways to expand

Question 203

Bronchitis is (4)

Answer 203

a condition in which the bronchioles & the trachea become irritated or infected, causing them to swell & produce excess mucus - excess mucus causes frequent coughing & difficulty breathing - It may become chronic, or long-lasting, when person exposed to cigarette smoke or other harmful pollutants --> the swollen airways & excess mucus may last for months or years - Heart must work harder to transport an adequate amount of O2 through the body

Question 204

Emphysema is (7)

Answer 204

- comes from Greek word meaning to puff up - Emphysema means over-inflated lungs--> Google: it's characterized by abnormal permanent enlargement of lung air spaces - occurs when the cilia lining the airways become damaged. --> cuz the cilia no longer filter & channel particles, the bronchioles become clogged & less air reaches the alveoli --> Air pressure builds up--> lungs appear inflated --> pressure eventually tears alveoli walls & some cells become oxygen deprived, causing heart & breath rat to increase --> body becomes stressed fatigued from spending more & more energy breathing - causes include smoking & longtime exposure to workplace chemical hazards like working in underground mines

Question 205

Chronic Obstructive Pulmonary Disease is (5)

Answer 205

AKA COPD a serious condition that occurs when chronic bronchitis & emphysema are found together - affected people may need external O2 source like a canister connected to nostrils - Meds like bronchodilators can be used to reduce inflammation & improve the airflow - if untreated, could lead to respiratory failure

Question 206

Cystic Fibrosis is (8)

Answer 206

a fatal genetic disease where abnormally thick mucus blocks airways - the mucus traps bacteria in lungs & leads to infection that damages lung tissue. - the mucus is very hard to dislodge, making breathing difficult - must participate in daily physical therapy to ease the flow of air. - affects may systems including the respiratory & digestive - Recent estimate: 1 in 3600 Canadian children are born with it - In 1989, Lap-Chee-Tsui (geneticist @ UFT) identified the gene for it - research for cure is ongoing

Question 207

SARS is (7)

Answer 207

AKA Severe Acute Respiratory Syndrome a serious pneumonia-like respiratory disease that is caused by type of coronavirus - the virus is spread through sneezing or coughing - causes an unusual lung inflammation, fever, & cough - breathing becomes very difficult & hospitalization may be necessary - some cases= fatal - 1st case= Nov 22, China. --> by the time it ran its course in July 2003, it had spread in 37 countries & caused about 800 global deaths

Question 208

SARS in Canada (4)

Answer 208

- all cases= Ontario - Doctors Sheela Basrur, Collin D'Cunha, James Young & others helped install infection control procedures - April 2003, Vancouver & Winnipeg scientists mapped genetic sequence of virus linked to SARS, important step to fighting the disease - SARS spread has been contained, but may still be present in animal populations & could return to human population

Question 209

Lung Cancer is (4)

Answer 209

a disease that starts when lung cells begin to behave abnormally by growing too fast & grouping together in abnormal ways - tumour= group of cancer cells - victims may develop recurring lung infections, chronic coughs, or difficulty breathing - 85% lung cancers are linked to smoking

Question 210

Lung Cancer treatment (3)

Answer 210

- there are 2 types of lung cancer & their treatments differ - some cases, surgery is used to remove lung tumours --> amount of lung tissue removed varies from a small wedge to an entire lung - drugs or different types of radiation may also be used to try to destroy the cancer cells

Question 211

Respirometer usage usage in respiratory conditions (2)

Answer 211

- doctors use them to measure a patient's breathing movements & lung capacity - blood & mucus samples are observed so abnormalities are identified

Question 212

Ultrasound, X-ray, CT scan, & MRI scan usage in respiratory conditions (1)

Answer 212

- after observing ur nose & throat, doctor may order a Ultrasound, X-ray, CT scan, or MRI scan to reveal the size & shape of airways & abnormality presence like tumours

Question 213

Florescent dyes & two-photon imaging microscope usage in respiratory conditions (1)

Answer 213

- with these tools, researchers can investigate molecular structure of individual cells of the respiratory systems like that of lung cancer cells

Question 214

Endoscope usage in respiratory conditions (2)

Answer 214

- used to remove obstruction in nasal passages - if problem source is in trachea or lungs, a endoscope called a bronchoscope may be inserted through nose or throat & passed into the lungs

Question 215

Laser usage in respiratory conditions (1)

Answer 215

- info from imaging tech may call for surgery, & lasers can be used to destroy obstructions during surgery

Question 216

Lung Transplant usage in respiratory conditions (2)

Answer 216

- considered when all other treatments fail - if lung damage is severe like in cystic fibrosis, a double lung transplant may be recommended

Question 217

Your _____________, _______________, & _____________ are closely connected in their structures & functions

Answer 217

Respiratory, circulatory, digestive - a problem in any one of these systems affects function of others & ur overall health

Question 218

What are 4 conditions that effect the respiratory, circulatory, & digestive systems?

Answer 218

1) Tuberculosis 2) Heart Failure 3) Smoking 4) Diabetes

Question 219

How does tuberculosis affect ur respiratory, circulatory, & digestive system (4)

Answer 219

-tuberculosis=bacterial infection that's spread when an infected person coughs or sneezes, releasing the bacteria into the environment - the bacteria usually target lungs.--> respiratory system - once in lungs, the bacteria sometimes crosses through the alveoli into the bloodstream --> Circulatory system - the blood then transports the bacteria to other tissues & organs, infecting them too. --> digestive system

Question 220

How does Heart Failure affect ur respiratory, circulatory, & digestive system (4)

Answer 220

- it's primarily a circulatory system problem - it can result in reduced nutrient transportation to cells, affecting digestive system - can result in leakage of fluid from capillaries in the lungs to the alveoli, causing respiratory problems

Question 221

Smoking (6)

Answer 221

- Cigarette smoke basically consists of microscopic carbon particles that are coating with toxic chemicals - toxic substances in tobacco smoke irritate the cells lining the bronchi & destroy the cilia. --> Without cilia, these cells lose their ability to move particles out of the respiratory system - smoker must cough frequently to try to clear the mucus that is no longer moved by the cilia --> when they lose the ability to remove these harmful particles from the lungs, smokers are at a greater risk for diseases caused by these particles - adding to cigarette smoke toxins, damage to respiratory system increases risk of damage from air pollution, dust, & airborne bacteria

Question 222

Smoking & Cancer (4)

Answer 222

- chemicals in cigarette smoke cause cancer - smokers=85% of all lung cancer cases - smokers have increases risk for cancer of gallbladder, pancreas, mouth, & throat --> connection to digestive system - women who smoke during pregnancy are more likely to babies born prematurely and/or with lower birth weight

Question 223

Smoking & Cardiovascular disease (4)

Answer 223

- after cancer, cardiovascular disease=2nd highest death cause in smokers - smoking raises bp & cholesterol levels in blood - smoking damage to respiratory system makes heart to work harder to deliver enough O2 to cells --> smokers have higher heart attack & stroke rate.

Question 224

Affects of second-hand smoking (3)

Answer 224

- some cigarette smoke toxin are in greater concentration in second-hand smoke, - it too can cause cancer - Children of smokers have a higher risk of developing colds, asthma, & allergies, & have more frequent hospitalizations for bronchitis & pneumonia

Question 225

Benefits by stopping smoking (2)

Answer 225

- huge health benefits no matter age or how long person has been smoking - after 10-15 years of not smoking, chances of lung cancer & heart disease return to normal

Question 226

Rather than viewing a problem as if it affected only 1 organ or organ system, doctors consider the health problem in the context of _______________________in the body

Answer 226

interacting systems - this approach to diagnosis & treatment of health problems has led to development of many new products & technologies

Question 227

Example of need to view a condition & its treatment holistically is ____________

Answer 227

diabetes

Question 228

Diabetes is

Answer 228

a group of diseases in which high levels of blood glucose result from a problem in insulin secretion, insulin action, or both.

Question 229

Insulin is (6)

Answer 229

a chemical produced by pancreas that controls the level of blood glucose - discovered by Canadians: Frederick Banting & Charles Best, in 1921 - If it isn't present or functioning properly, glucose builds up in blood & can't be used by cells for energy. ---> diabetes patients may suffer from fatigue cuz the sugar that is usually used to make energy by cellular respiration is not available to cells but remains in blood - over time, high blood glucose can result in serious health issues like blindness, kidney problems, & heart disease - high blood glucose can damage coronary arteries by increasing artery plague --> can lead to atherosclerosis, which can increase bp

Question 230

Type 1 Diabetes (4)

Answer 230

- pancreas cells are damaged & thus can't produce insulin - exact cause isn't understood - although several genes are associated with onset of this disease, appears that cellular environment also play a role in its development - rn Type 1 diabetes can't be prevented, but effects can be controlled.

Question 231

Type 2 Diabetes (4)

Answer 231

- in this type, the body cells don't respond to insulin appropriately - Type 2 diabetes cases are increasing dramatically --> reasons 4 this increase including rising obesity rates & the increasingly sedentary lifestyle of Canadians --> recent research= 29% Canadians watch TV for 15 or + hours/week, 15% Canadians report using computer for 11 or + hours/week for leisure. --> This sedentary lifestyle increases extra weight - excess body fat seems to interfere with the body's ability to use insulin effectively

Question 232

Diabetes Treatment (5)

Answer 232

- patients must have their insulin replaced, usually through daily injections - to administer correct amount, diabetics test their blood sugar via blood tests - physical activity, nutrition, & emotional state all effect blood sugar levels, & so insulin must be administered accurately - patients must make careful choices of physical activities & foods to control blood sugar levels - planning & timing of meals is also important in maintaining levels

Question 233

Genetic tech & Diabetes (4)

Answer 233

- enabled doctors to identify genes that seem to control the body's response to diabetic meds --> more personalized approach can occur - experimental treatment for Type 1 diabetes includes transplanting cells from donor pancreas to patient's to produce insulin - possibly, we can deliver the insulin gene into cells lining small intestine using nanoparticles--> by adding the gene to intestinal cells, the cells can be reprogrammed to produce insulin needed

Question 234

Tech innovations & diabetes (3)

Answer 234

- imaging tech like MRI & CT scans enable docs to view internal organs in 3d - in recent years, NASA imaging tech used to view landforms from space have been used to analyze pancreas images - sophistication of imaging tech has increased but availability outside urban centres is still a challenge

Question 235

Research shows that a healthy & active lifestyle can reduce the risk of Type 2 diabetes by_____.

Answer 235

50% - exercise can improver overall health levels by increasing blood flow to cells, normalizing bp, & reducing blood glucose levels.