Human Bio Year 11 ATAR Sem 1

What is the main function of the digestive system?

To break down food and absorb the nutrients obtained from digestion.

Where does most nutrient absorption occur?

Small intestine

What does bile do?

Emulsifies fats (breaks them down into smaller pieces)

What is peristalsis?

The wave-like muscle contractions that move food through the digestive tract.

Main organ of the excretory system?

The kidneys

3 main functions of the kidneys?

1. Filter waste from the blood

2. Balance salt and water levels in the body

3. Regulate blood pressure and blood cell production

What is the functional unit of the kidneys?

Nephron

What is the function of a nephron?

The main functions of the nephron is to filter waste from the blood, reabsorbing useful substances like glucose, and secreting waste into the urine.

3 main processes in urine formation?

1. glomerular filtration

2. tubular reabsorption

3. tubular secretion

Where does filtration occur?

Glomerular Capsule/Bowman's Capsule

What is Dialysis?

An artificial process that removes waste and toxins from the blood when kidneys fail

Two types of dialysis?

Peritoneal dialysis and hemodialysis.

Main Function of the Circulatory System

Transport nutrients and oxygen through the body

List the 3 types of blood vessels

arteries, veins, capillaries

Which side of the heart pumps oxygenated blood?

Left side

What prevents backflow of blood into the heart

Valves in the heart prevent backflow by only opening in one direction and close tightly if blood is about to go the wrong way

What are alveoli and what is their function?

Alveoli are tiny air sacs in the lungs where gas exchange takes place.

What is diffusion?

The movement of particles from an area of high concentration to an area of low concentration. It is passive and doesn't require energy

Define osmosis

Osmosis is the movement of water molecules across a semipermeable membrane from an area of high water concentration to an area of low water concentration.

How does gas exchange work in the alveoli?

Oxygen (blood to alveoli) and carbon dioxide (alveoli to blood)

Why are alveoli good for gas exchange?

1. They are one cell thick and surrounded by elastic connective tissue to force air out

2. Large surface area that makes more space for gas exchange

3. Lots of capillaries

Define Facilitated Transport

Facilitated transport is the passive movement of molecules across a cell membrane through protein carriers.

What is the role of the trachea?

The role of the trachea is to transport air to and from the lungs

What is the difference between inspiration and expiration?

Inspiration is the active process of bringing air into the lungs. During inspiration the diaphragm contracts and the lung volume increases. Expiration is the passive process of releasing air. During expiration the diaphragm is more relaxed and the lung volume decreases.

What is the role of the trachea?

To carry air to and from the lungs.

What are the functions of the bronchi and bronchioles in the respiratory system?

The bronchi carry air from the trachea into each lung and bronchioles are smaller bronchi that distribute air throughout the lungs and lead to the alveoli, where gas exchange occurs

Which of the structures related to pulmonary circulation carries oxygenated blood?

Pulmonary vein

What are RBC's, WBC's, and Platelets also known as?

RBC=erythrocytes

WBC=leucocytes

Platelets=thrombocytes

Process for aerobic respiration

Glycolysis occurs first (glucose molecule broken down into 2 pyruvate). Pyruvate converted to acetyl CoA and CO2 removed from pyruvate molecules. Then enters citric acid cycle. Electron transport system (oxygen molecules form water) uses oxygen.

How much ATP at max can be produced per glucose molecule?

38 ATP

Define metabolism and explain the connection between metabolic reactions and weight gain.

Metabolism is the sum of all the chemical reactions occurring in the body. Catabolism is the break down of food molecules into smaller ones to produces energy. Anabolic reactions use energy from catabolic reactions. If more catabolic reactions than anabolic, the excess is stored as fat

How do cells work together to form multicellular organisms?

Cells form tissues > tissues form organs > organs form systems (multicellular organisms are made up of multiple systems)

Vigorous exercise is a type of anaerobic exercise. What can commonly cause muscle pain felt in these types of exercises?

Lactic acid build up in the muscles.

The inferior vena cava brings blood back to the heart from the

liver

The production of urea occurs mainly in the

liver

Which of the following minerals is essential for regulating the chemical composition of body fluids

sodium

Which organelle is associated with the modification and packaging of proteins of the cell

Golgi body