Bio D.1-D.3

What are macromolecules?

Large organic molecules with three main types: carbohydrate, lipids/fats, proteins

How are molecules assembled and broken down?

Assembled through dehydration synthesis and broken down through hydrolysis

What is the main role of carbohydrates?

Provide shot-term energy

What are the three classifications for carbohydrates?

Monosaccharides, Disaccharides, Polysaccharides

What is the main function of lipids?

Long-term energy storage

What is the difference between saturated and unsaturated fatty acids?

Saturated fatty acids have only single bonds (solid at room temp) and unsaturated fatty acids have double bonds (liquid at room temp)

What is hydrogenation used for?

Converting unsaturated fats to saturated fats

What are proteins?

Amino acids molecules bonded together that do NOT provide cells with energy

What are enzymes?

Biological catalysts made of proteins

What are the two models of proteins?

1. Lock and key

2. Introduced fit

What are accessory organs?

Those which aid in digestion but do not actually handle food (salivary glands, liver, gallbladder, pancreas)

What is the digestive tract?

Those which actually move food through the body (mouth, esophagus, stomach, small intestine, large intestine, rectum, anus)

Explain the mouth

-where digestion begins

-contains salivary glands

-physical digestion occurs here (creation of bolus)

-the breaking down of food increases surface area for chemical digestion

Explain the esophagus

-where food travels from the mouth to the stomach

-bolus food stretches its walls which activates wavelike muscle contractions

-has an esophageal sphincter at the end which closes tightly to prevent stomach acid from splashing up

Explain the stomach

-food undergoes both physical and chemical digestion from the churning process and stomach acid

-chyme is produced as food mixes with gastric juice

-this is where protein digestion begins

Explain the small intestine

-its main function is to complete the digestion of macromolecules to absorb nutrients

-4x the length of the large intestine

-covered in microvilli

-divided into three regions: duodenum, jejunum, and ileum

What is the duodenum?

The first 30 cm of the small intestine that serves as an important site for chemical digestion of chyme. It is the shortest and widest section which forms a U-shape

What is the jejunum?

The second section of the small intestine that contains even more folds and secretory glands. It continues the break down of food

What is the ileum?

The last section of the small intestine that absorbs nutrients and pushes remaining material to the large intestine. It contains smaller and fewer villi

Explain the large intestine

-the final part of the digestive tract

-only 1.5 m long with a greater diameter than the small intestine

-its main function is to concentrate and eliminate waste material

-contains the colon which is the largest part of the large intestine

What is the newly hypothesized purpose of the appendix?

It serves as a storage site for the “good” bacteria that aids in digestion

What does the pancreas do?

delivers 1L of pancreatic fluid to the duodenum every day which contain enzymes that digest proteins into smaller polypeptides

What does the liver do?

produces bile that emulsifies fats

What does the gallbladder do?

serves as a storage site for bile that can inject bile salts as needed into the small intestine

What are disorders that accessory organs can have?

-Hepatitis (inflammation of liver)

-Cirrhosis (chronic disease of liver)

-Gallstones (form in gallbladder)

What are the main digestive system disorders?

-Ulcers

-Chron’s disease

-Colitis

What is respiration?

Involves the gas exchange between an organism and the environment that supplies oxygen to the cells of the body for the breakdown of glucose.

List the parts of the respiratory tract

Nasal passages, pharynx, epiglottis, glottis, larynx, trachea, bronchi, bronchioles, alveoli, lungs, and diaphragm

Explain the nasal passages

-lined with ciliated (hair-like) cells and cells that secrete mucus, these cells filter and moisten air

*cilia also increase surface area

-the turbinate bones increase surface area

-heat from the blood vessels warms the air

Explain the pharynx

-the passageway into the respiratory system (aka the throat)

-air space at the back of the mouth and nasal cavity

-carries food and water to the digestive system

-two openings from the pharynx (esophagus and trachea)

Explain the epiglottis

-a flap of cartilage that lays behind the tongue

-serves to close the opening to the trachea when a person swallows

Explain the glottis

-the opening to the trachea

-must be covered when swallowing in order to prevent food/water from entering the lungs

Explain the larynx

-commonly called the voice box

-contains the vocal chords

-located at the upper end of the trachea

-the adams apple is a layer of cartilage that protects the larynx

What are vocal chords?

Vocal chords are two thin sheets of elastic ligaments that vibrate as air is force past them

Explain the trachea

-also called the windpipe

-carries air to lungs

-covered in cilia that are coated in mucus

-rings of cartilage that keep the trachea open

Explain the bronchi

-carries air from the trachea into the left and right lungs

-supported with cartilage rings

-lined with cilia and mucus

Explain the bronchioles

-smaller airways inside each lung

-less than 1 mm in diameter

-made of smooth muscle (do not contain cartilage)

-lined with cilia and mucus

Explain the alveoli

-tiny clusters of air sacs found at the end of bronchioles

-the site of gas exchange

Explain the lungs

-the primary organ of the respiratory system

-divided into lobes (right lung has 3 lobes, left has 2 to leave room for the heart)

Explain the pleural membrane

-thin, fluid-filled membrane surrounding the lungs

-allows the lungs to expand and contract with the movement of the chest

Explain the diaphragm

-a dome shaped sheet of muscle just below the lungs

-separates the lungs from the stomach and liver

-aids in breathing movements

Explain intercostal muscles

-muscles between the ribs

-allows ribs to expand and contract

What is the process for inhalation?

The intercostal muscles contract, lifting the rib cage up and out. At the same time the diaphragm contracts and pulls downward. As the lungs expand, air moves in.

What is the process for exhalation?

The intercostal muscles relax, allowing the rib cage to return to its normal position. The diaphragm also moves upward, resuming its domed shape. As the lungs contract, air moves out.

How does breathing work?

breathing relies on the movement of gases from an area of high pressure to low pressure

What is the lymphatic system?

Network of vessels, glands, and nodes spread throughout the body, closely associated with the capillaries of the cardiovascular system. It collects lymph fluid and helps maintain the balance of fluids in the body.

What is the main purpose of the lymphatic system?

protect the body against infections

What is an antigen?

a substance, usually protein, that stimulates the formation of an antibody

What is an antibody?

a protein formed with blood that reacts with an antigen

What is a pathogen?

an organism causing disease to its host

Where do white blood cells mature?

lymph nodes

Why do lymph nodes swell when you are sick?

lymph nodes contain macrophages (a type of white blood cell that traps and destroys bacteria) and infections lead to an increase in the number of macrophages to fight off sickness which causes swelling

What is the first line of defense in immunity?

physical and chemical barriers of the body

What is the second line of defense in immunity?

also called the non-specific line of defense, white blood cells known as phagocytes will act to engulf and destroy foreign pathogens in bloodstream (this results in an inflammatory response)

What are the three types of phagocytes?

Monocyte, Macrophage, and Neutrophil

What is the third line of defense in immunity?

also known as the specific line of defense or antibody-meditated immunity, specific white blood cells called lymphocytes target pathogens according to the specific markers the represent