Animal tissues, organs and organ systems Flashcards
What is function of spongy mesophyll
To allow carbon dioxide to diffuse through the leaf and increase surface area
What is the function of the layer of palisade cells
Absorbs light
What is the function of epidermis
Allows light to reach the palisade cells
What is the function of waxy cuticle
Protects the leaf without blocking out light
What is xylem and phloem and what do they do
Tissues which transport substances around plant
- Xylem - Distributes water and dissolved minerals upward through the plant from roots to the leaves
- Phloem - Carries food downwards from leaves to the roots
What is mesophyll
Tissues which carry out photosynthesis
What is epidermal tissue
Tissue which covers the plant
What are organ systems
A group of organs that perform a particular function
What is an organ
A group of tissues
What is epithelial tissue
Covers some parts of bodies providing protection
What is a glandular tissue
Produces substances such as enzymes and hormones
What is a muscular tissue
A type of tissue that contracts to bring about movement
What is a tissue
A group of cells with similar cell structure and function
How are capillaries adapted to their function
- Function : Enables transfer of substances between the blood and tissues
- Walls are one cell thick - short diffusion path
- Permeable walls - Substances can diffuse across
- Narrow Lumen - Blood moves slowly - more time for diffusion
How are veins adapted to their function
- Function : Carry blood towards the heart
- Wide lumen - enables low pressure
- Valves - prevent backflow of blood
How are arteries adapted to their function
- Function : Carry blood away from the heart
* Thick muscle layer - adds strength to resist high pressure
What are 3 types of blood vessels in the body
- Arteries
- Veins
- Capillaries
What is the approximate value of the natural resting heart rate
70 beats per minute
What is purpose of coronary artery
Coronary arteries supply the heart muscle with oxygenated blood
What is the purpose of valves in the heart
Prevent the backflow of blood
What are four main blood vessels associated with the heart
•Aorta (left) - Carries oxygenated blood from heart to the body
•Pulmonary vein (left) - Carries oxygenated blood
from the lungs to the heart
- Vena cava (right) - Carries deoxygenated blood from the body to the heart
- Pulmonary artery (right) - Carries deoxygenated blood from the heart to the lungs
Why is the wall of the left ventricle thicker
The left ventricle has to pump blood at a higher pressure around the whole body
How many chambers does the heart have and what are they called
4 - right atrium, right ventricle , left atrium, left ventricle
Where does blood pumped by left ventricle go
Body tissues
Where does blood pumped by the right ventricle go
The lungs
How does double circulatory system work
- One pathway carries blood from the heart to the lungs - where exchange of oxygen and carbon dioxide takes place
- One pathway carries blood from heart to the tissues
What is the purpose of the circulatory system
Carries oxygen and other useful substances to bodily tissues and removes waste substances
What is the heart
An organ that pumps blood around the body
Where is bile made and stored in the body
Bile is made by the liver and stored in the gallbladder
What is the role of enzymes in digestive system
Enzymes acts as biological catalysts which speed up rate of biological reactions without being used up
What is role of lipases in the digestive system
Lipases break down lipids into fatty acids and glycerol
What is the lock and key hypothesis of enzyme function
The shape of the enzyme active site and the substrate are complementary so can bind together to form an enzyme - substrate complex
How does the shape of an enzyme affect its function
Enzymes have a specific active site which is complementary to their substrate
What is the role of the large intestine in the digestive system
Absorbs water from undigested food producing faeces
What is the role of the liver in the digestive system
Produces bile (stored in the gallbladder) which emulsifies lipids and allows the lipase enzyme to work more efficiently
What is the role of the small intestine in the digestive system
This is where soluble food molecules are absorbed into the blood stream
What is the role of the stomach in the digestive system
Produces hydrochloric acid which kills any bacteria
What is the role of the pancreas and the salivary gland in the digestive system
The pancreas and the salivary gland are glands which produce digestive juices containing enzymes
What is the main function of the digestive system
To digest food and absorb the nutrients
What is role of lipases in the digestive system
Lipases breaks down lipids into fatty acids and glycerol
What is a tissue?
A group of cells with a similar structure and function
What is an organ?
A group of tissues working together for a specific function
What is an organism ?
Work together to form organisms
What are 3 main nutrients in food ?
Carbohydrates (e.g. starch), protein and lipids (fats)
What are main organs that make up digestive system ?
The main organs that make up the digestive system (in order of their function) are the mouth, oesophagus, stomach, small intestine, large intestine, rectum and anus
What do digestive enzymes do?
Break down large insoluble molecules into smaller soluble ones
Where are digestive enzymes made?
In glands
What are the three digestive enzymes you need to know?
Amylase (a Carbohydrase), Protease and Lipase
Where is amylase made?
The salivary glands, pancreas and small intestine
Where is protease made?
In the stomach, the pancreas and the small intestine
What does protease do?
Catalyses the breakdown of proteins into amino acids
Where is lipase made?
In the pancreas and small intestine
What does lipase do?
Catalyses the breakdown of lipids (fats and oils) into fatty acids and glycerol
What do enzymes do ?
Speed up chemical reactions
What happens to the active site?
It is where the substrate attaches to
What is substrate ?
Molecule that the enzyme breaks down
