analysis

Question 1

ingestion

Answer 1

food enters oral cavity

Question 2

digestion

Answer 2

teeth chew the food, saliva moistens.
Enzyme in saliva called amylase breaks down carbs
Muscular tongue pushes food back to pharynx
food streches walls of esophagus and moves down through wave contractions called peristalisis

Question 3

food enters the stomach as

Answer 3

bolus. A small ball of food that has been moistened so it can be swallowed. Enters stomach through the cardiac sphincter. Stomach has extensive folds called rugae. Layers of smooth muscle help contract and break down muscle even further.

Question 4

esophagus to stomach

Answer 4

peristaltic contractions move food to stomach where storage and mixing of food occurs
Cardiac sphincter at the top. Pyloric sphincter at the bottom to keep food from getting out. n

Question 5

step 2 digestion

Answer 5

food moves in and out of the stomach through sphincters. Stomach contracts and relaxes to churn food. Hydrochloric acid: breaks down food, destroys foreign organisms in food.
pepsin: enzyme that breaks down proteins into polypeptides.
mucus: protects stomach lining from acid and ulcers. Some absorption of water, medicine, and alcohol here.

Question 6

gastrin

Answer 6

nerves in an inner layer in the stomach detect food and initate release of the hormone gastrin. Gastrin released into bloodstream. Transported to gastric cells of stomach where it stimulates gastric juice release.

Question 7

pepsin

Answer 7

the active form of pepsinogen. Protein digesting enzyme produced in the stomach.

Question 8

chyme

Answer 8

the pulpy acidic fluid which passes from the stomach to the small intestine, consisting of gastric juices and partly digested food. Is released into the duodenum through the pyloric sphincter.

Question 9

3 parts of the small intestine

Answer 9

duodenum, jejunum, illeum. Secretes the enzyme peptidase which completes digestion of proteins.

Question 10

duodenum

Answer 10

enzymes added, digestion. Neutralizes acidic chyme from stomach and inactivates pepsin back to pepsinogen.

Question 11

jejunum

Answer 11

digestion, some absorption.

Question 12

ileum

Answer 12

majority of nutrient absorption

Question 13

stage 3 absorption

Answer 13

primary site of nutrient absorption to the blood. 80% of nutrient absorption occurs here- diffusion. Only the small intestine can absorb lipids (fats), carbohydrates, and amino acids (from proteins). Small intestine is lined with villi and microvilli:
Finger-like projections that increase surface area for absorption.

Question 14

vili

Answer 14

small fingerlike projections

Question 15

micro vili

Answer 15

microscopic projections of epithelial cells.

Question 16

capillary network

Answer 16

All nutrients, except fats, enter bloodstream via capillaries.

Question 17

Lacteal

Answer 17

Lymphatic vessel through which fats enter circulatory system.

Question 18

large intestine

Answer 18

Also known as the colon
Primary function is to reabsorb fluids and electrolytes. Fecal matter is stored here before elimintaion through the anus. Harmless bacteria live here producing vitamins K and B. Small and large intestine join at the caecum with the illeocal valve

Question 19

Appendix

Answer 19

Small organ attached to cecum.

Question 20

egestion/excertion

Answer 20

occurs in the large intestine, toxic wastes are removed.

Question 21

liver

Answer 21

the largest organ in the body. produces bile, which breaks down fats. LIver filters the blood by extracting toxins and preparing for nutrient circulation. Stores glucose as glycogen.

Question 22

gallbladder

Answer 22

recieves, stores, and concentrates bile from liver. When fats enter duodenum, duodenum releases hormone CCK (Cholecystokinin). CCK signals gallbladder to secrete bile to duodenum to digest fats

Question 23

carbohydrate structure.

Answer 23

Many of the carbohydrates we ingest are in polysaccharide form, and must be broken down into monosaccharides in order to be absorbed into the bloodstream. Monosaccharides - the smallest and most usable form of carbohydrates are absorbed by villi and enter bloodstream for transport to body cells.

Question 24

chemical digestion of carbohydrates

Answer 24

Salivary amylase: Breaks the long sugar chain starch into smaller maltose molecules.Pancreatic amylase: Acts on remaining polysaccharides (long sugar chains) in the small intestine.
Jejunum: Cells in the inner lining produce enzymes that breaks down disaccharides (smaller sugar molecules).

Question 25

Protein Structure

Answer 25

Proteins are created with chains of amino acids. The proteins you ingest in your food are typically complex and need to broken back down into amino acids that can easily be absorbed by your bloodstream.

Question 26

chemical digestion of proteins

Answer 26

Protein digesting enzymes are first released as inactive forms so that they do not digest the cells that produce them. The inactive enzymes only become active when they reach the digestive tract. Pepsin is produced in the stomach lining and breaks protein molecules into long-chain amino acids. As it enters the small intestine and pH become alkaline, it reverts to it’s inactive form, pepsinogen. Proteases in the small intestine (from the pancreas) break proteins into amino acids. Single amino acids are absorbed by villi directly into the blood stream.

Question 27

Structure of Fats

Answer 27

Fats are often in the form of triglycerides when we ingest them, and need to be broken down into smaller molecules to be absorbed by the blood stream.

Question 28

Chemical Digestion of Fats

Answer 28

Mechanical digestion of fats (in mouth and stomach) converts pieces of fat into smaller fat globules. Duodenum: Bile from the gallbladder makes fat globules [emulsifies them] smaller and spreads them through the chyme. Lipase (enzyme from pancreas) chemically digests (splits) fat into glycerol and fatty acids. Smaller fat molecules are absorbed by villi into the bloodstream.

Question 29

Chrons disease

Answer 29

Chronic inflammatory bowel disease. Most common in small/large intestine. Causes: Possible hereditary link to autoimmune disease (25%). Possible bacterial or viral infection.Abdominal pain. Intestinal bleeding. Diarrhea. Nausea & vomiting. Loss of appetite. Weight loss. Fever.Barium x-ray. Colonoscopy.

Question 30

stomach (gastric) cancer

Answer 30

Cancer of tissues lining stomach. Exact cause unknown Risk factors:H. pylori infection. Smoking. Poor diet. Nausea and vomiting. Heartburn and indigestion. Fatigue. Stomach pain. Feeling full after eating little.Endoscopy & biopsy. CT scans. Barium Swallow X-ray. Radiation therapy & chemotherapy To shrink tumor. Gastrectomy Partial or total removal.

Question 31

cirrhosis

Answer 31

Scarring of the liver. Leads to loss of liver function. Caused by chronic damage to liver (e.g., hepatitis & alcoholism). Fatigue Loss of appetite. Easy bruising & bleeding. Nausea & vomiting. Fluid retention in abdominal region.Blood tests. Liver Biopsy. CT or MRI scan. Ultrasound.Damage cannot be reversed. Avoidance of alcohol. Liver transplant.

Question 32

respiration

Answer 32

the exchange of oxygen and carbon dioxide between an organism and its external environemnt.The respiratory system supplies O2 to cells & removes CO2.

Question 33

includes 3 different processes

Answer 33

Ventilation (or Breathing) Gas Exchange (2 types that differ in location) External Respiration Internal Respiration Cellular Respiration

Question 34

ventilation

Answer 34

The movement of gases between the external environment and the respiratory membrane of organisms. A "respiratory membrane" is the location where the exchange of gases occurs by diffusion. In humans this membrane is the lung.

Question 35

External gas exchange

Answer 35

External Respiration: The exchange of gases between the atmosphere and the blood. Gas exchange between the alveoli and blood vessels (pulmonary capillaries). The alveoli must be moist to allow for diffusion.

Question 36

External respiration continued

Answer 36

O2 diffuses into the capillaries and CO2 diffuses out to the alveoli. The blood carries the oxygen from the lungs to the body cells.

Question 37

internal respiration

Answer 37

the exchange of gases between the blood and body cells. Oxygen diffuses from the blood to the cells; Carbon dioxide diffuses from the cells to the blood.

Question 38

3. Cellular Respiration

Answer 38

Occurs in the cytoplasm and mainly the mitochondria We breathe in oxygen so that it can react with glucose in the mitochondria and release energy (ATP).

Question 39

Nostrils (Nasal Cavity)

Answer 39

Air enters through nostrils Contains mucus and tiny hair (cilia) that trap dust and foreign particles Warms and moistens incoming air

Question 40

Pharynx

Answer 40

Located at the back of the mouth where nasal and oral cavities join Branches into trachea and esophagus

Question 41

Larynx

Answer 41

Also called voicebox Located in trachea below epiglottis Contains vocal cords (2 thin elastic bands). The incoming air causes the cords to vibrate, producing sound. Different position of vocal cords produces different sounds. Larynx is protected by a thick band of cartilage, called the Adam's apple.

Question 42

Trachea

Answer 42

Also called windpipe The trachea filters the air we breathe and branches into the bronchi. The Epiglottis is located at the top of the trachea - the epiglottis prevents food from entering the trachea and lungs. If food does get into the trachea, the cough reflex removes the food. Tubular Structure lined with cartilage rings on the outside and ciliated mucus-secreting cells on the inside.

Question 43

Lungs

Answer 43

Bronchi (Singular: bronchus) Animals have two bronchi (left and right) Branch off of the trachea and carry air directly into the lungs, and branch into many smaller airways called the bronchioles. Bronchioles Network of smaller tubes located within each lung Dilation and contraction of the bronchioles can increase or decrease the resistance of air movement. Each bronchiole ends in alveolar sac.

Question 44

Lungs-Alveoli

Answer 44

Bronchioles become smaller and smaller until they reach a dead end in air sacs called alveoli. This is where the actual gas exchange (Oxygen and Carbon dioxide) occurs between air and blood via capillaries 150 million alveoli per lung Increases surface area of gas exchange

Question 45

Diaphragm

Answer 45

Band of dome-shaped muscle separating the chest/thoracic cavity (lungs and heart) from the abdominal cavity (all other organs). Regulates the pressure in the chest cavity and helps in our efforts to inhale and exhale.

Question 46

inhalation

Answer 46

Ribs move out, chest cavity enlarges. Pressure decreases (more space for gas). Air will rush in from higher pressure

Question 47

Exhalation

Answer 47

Ribs compress, chest cavity gets smaller * Pressure increases (less space for gas) * Air escapes to lower pressure environment

Question 48

breathing

Answer 48

Involuntary inhalation and exhalation. * Delivers O2 to alveoli and removes CO2 * Medulla oblongata * Brain region that controls breathing.

Question 49

control of breathing

Answer 49

Chemoreceptors detect change in blood pH * Blood high in CO2 has lower than normal pH. * Drop in pH causes medulla oblongata to stimulate breathing * Note: Chemoreceptors are nerve cells in the medulla oblongata

Question 50

OXYGEN TRANSPORT

Answer 50

Most oxygen is carried throughout the body by attaching to hemoglobin (Hb) in red blood cells. Hb readily picks up oxygen in areas of high concentration and releases it in areas of low concentration. Oxygen is temporarily bound to Hb by hydrogen bonds. * oxygen + hemoglobin → oxyhemoglobin * Some oxygen is carried by dissolving in the plasma of blood

Question 51

carbon dioxide transport

Answer 51

Most carbon dioxide is carried as bicarbonate ions (HCO3-) in the blood. It is picked up by red blood cells in areas of high concentration and converted to bicarbonate. Then, in areas of low concentration, it is converted back to carbon dioxide and released from red blood cells. * CO2 + water → carbonic acid → HCO3- * Some carbon dioxide is carried by Hb as carboxyhemoglobin in red blood cells. As well, some carbon dioxide is carried by dissolving in the plasma of blood

Question 52

the circulatory system has 4 main functions:

Answer 52

1. Transport O2 and nutrients (eg. glucose) 2. Transport Wastes (eg. CO2 and urea) 3. Maintain body temperature 4. Circulate chemical messengers (hormones)

Question 53

There are 3 main parts of the Circulatory System:

Answer 53

1. Blood 🡪 transports various materials 2. Blood vessels 🡪 network of tubes where blood moves through 3. Heart 🡪 a pump that pushes blood through blood vessels

Question 54

MAIN FUNCTIONS OF BLOOD

Answer 54

transports materials. Removes wastes from body tissues/ cells and transports them to organs for removal from the body

Question 55

erythrocytes

Answer 55

Disk – like shape for flexibility and increased surface area Contain hemoglobin molecule that allows RBC to bind carry O2. Produced in the bone marrow Function: To transport oxygen to all parts

Question 56

blood cells

Answer 56

Red blood cells- eryhtocytes White blood cells- leukocytres platelets (thrombocytes)

Question 57

White Blood Cells (WBC)

Answer 57

Makes up less than 1% of blood volume. Defends the body from disease and infection. Destroys foreign microbes and damaged cells. A high number of WBC may indicate an infection (or leukemia). Pus = living and dead WBCs and foreign microbes.

Question 58

Platelets

Answer 58

Cell fragments. Produced in bone marrow Plays a role in blood clotting.

Question 59

Arteries – Arterial System

Answer 59

Have thick, muscular, elastic walls Carry blood AWAY from the heart Blood flows through under HIGH pressure. Arteries branch into smaller and narrower vessels called arterioles, which then branch further into capillaries. Arterioles have smaller diameter than arteries and are less elastic, BUT the contraction and relaxation of arterioles is the major determinant of the overall blood pressure.

Question 60

There are 5 types of Blood Vessels: (this is their order)

Answer 60

1. Arteries 2. Arterioles 3. Capillaries 4. Venules 5. Veins

Question 61

Capillaries

Answer 61

Smallest and tinniest blood vessels with very thin walls (only one cell thick) So thin, that blood cells travel in single file. Capillaries link arteries and veins together (connects arterial & venous systems).

Question 62

Veins – Venous System

Answer 62

Thinner, less elastic walls. Carry blood back towards the heart Blood flows through under LOW pressure Most veins must work against gravity Contain valves that make sure blood moves in the right direction employ the work of smooth muscles to help push blood back to heart. Veins collect blood from smaller and narrower vessels called venules, which then receive blood from capillaries