Strand 1 Living Things Flashcards
(44 cards)
Why do we dissect Toadz and give some materials on dissecting a toad ?
We dissect a toad because its digestive system is similar to many animals and humans some of the materials that we need to dissect a toad is : toad, dissecting forceps and a scapel.
What are some of the precautions we should take when dissecting a toad
Be careful not to cut too deeply because it may damage the heart or any other internal organs
Why do we dissect the bottom side
Because the backbone is found on the top side
What is the digestive system
It is the digestion system whereby foods are broken down into simpler forms for digestion
What are the two types of digestion
Mechanical digestion – teeth grind and break up food into smaller pieces and it occurs in the mouth.
Chemical digestion( enzymes)– Breakdown of food into small simplest form that is suitable for absorption
What is peristalsis
Wave like contraction that pushes food around
Describe the movement of food through the tract
Ingestion – taking food in
Physical digestion – grinding up a food
Chemical digestion – breakdown of food
Absorption – simple molecules are absorbed
Assimilation – making new compounds from the absorbed molecules
Egestion – undigested food in removed
The food test of starch glucose protein
Starch – (iodine solution used ) iodine solution is added .. positive results- bluish black negative - light brown
Glucose - ( benedicts solution or fehling solution used )small amount added n heat gently positive - brick red negative - light blue
Protein - (biuret solution used) several drops positive- purple negative- light blue
Another name of walls of the alimentary canal and what is it
Another name for alimentary canal is small intestine and it acts as a Steve which means that it only allows small materials to pass through it
How are molecules broken down into smaller molecules
By the visking tube which behaves like the walls of the intestine it has small holes and only glucose is able to pass through it is also known as semi permeable
What is circulatory system, what is it made of?
The circulatory system carries digested food oxygen and water to the cells it is made up of blood ,blood vessels and heart
Another name for red blood cells what is it made of and what does it do
Red blood cells are also known as erythrocytes end it is made up of haemoglobin which binds oxygen and gives blood its red color
What is white blood cells what does it do
White blood cells are leukocytes and it provides protection against illness and diseases
Platelets?
They are produced from red bone marrow and it helps blood to clot when the skin is cut
Plasma?
Is 90% water and contains dissolved substances such as hormones waste materials and digested food
Arteries? Veins? Capillaries?
Arteries carry blood away from the heart and contain blood under high pressure
Veins carry blood to the heart end it contains blood under low pressure
Capillaries joint arteries to veins and it has very low blood pressure and also it is where gas exchange takes place
Heart?
The heart pumps blood around the body average heart pumps over 5 L of blood in the walls of the heart contains muscle fibers
What are the two main circulation loops
The heart live in Loop and the heart body loop ( definition)
What is the respiratory system
The main organ is lungs where oxygen is added to the blood and carbon dioxide is removed
What is respiration
Gas exchange or process where by digested food is combined with oxygen to release energy that is needed by the body cells to carry out function
What is the word equation for respiration
Glucose plus oxygen equals carbon dioxide plus water
What is the lungs? And what is alveoli
Lungs are two sponge bags of tissue of tiny airspace is called alveoli
Alveoli Has very thin walls and has millions of tiny airspace
Name the process of Inhaling in the process of exhaling
Inhaling – diaphragm muscles pull the diaphragm downwards increasing the volume in the Thorax
Exhaling- muscles between ribs relax and thorax returns to its original shape or size
The comparison of expired and inspired air
Oxygen – inspired air equals 21%, expired air equals 16%
Carbon dioxide – inspired air equals 0.04%, expired out equals 4%
Nitrogen - inspired air equals 78%, expired out equals 78%
Temperature – inspired and equals variable, expired air equals always high
