4. THE CHEMICAL BASIS OF LIFE Flashcards
1
Q
- What are organisms composed of?
A
- matter
2
Q
- What is the definition of matter?
A
- anything that takes up space and has mass
3
Q
- What is matter made up of?
A
- elements
4
Q
- What is the definition of elements?
A
- substances that cannot be broken down into other substances through chemical reactions
5
Q
- How many elements exist in nature, and where are they listed?
A
- 92 elements exist in nature
- they are listed in the Periodic Table
6
Q
- What are compounds?
A
- a substance consisting of 2 or more elements
- that are combined in a fixed ratio
- compounds have different characteristics from elements
7
Q
- What elements make up 96% of living matter?
A
- carbon (C)
- hydrogen (H)
- oxygen (O)
- nitrogen (N)
8
Q
- Which elements make up most of the remaining 4% of living matter?
A
- Calcium (C)
- Potassium (K)
- Sodium (Na)
- Phosphorous (P)
9
Q
- Which elements are only required by the organism in minute quantities?
They make up 0.01% of living matter
A
- Iron (Fe)
- Iodine (I)
- Selenium (Se)
- Zinc (Zn)
- THEY ARE CALLED TRACE ELEMENTS
10
Q
- What is the name given to the condition of iodine deficiency in the body?
A
- hypothyroidism is when there is an iodine deficiency in the body
- it leads to Goitre (an enlargement of the thyroid gland)
11
Q
- What is Iodine?
A
- it is an essential trace element for the production of thyroid hormones
- thyroxine and triiodothyronine are examples of thyroid hormones
12
Q
- What is the name given to a condition caused by an Iron Deficiency?
A
- Anaemia
- Iron (Fe) is a part of the haemoglobin structure
- it holds oxygen in the haemoglobin molecule
13
Q
- What does each element consist of?
A
- a specific atom
14
Q
- What is an atom?
A
- it is the smallest unit of matter that still retains the properties of an element
- an element and it’s atom have the same symbol
15
Q
- What are atoms composed of?
A
- smaller parts called subatomic particles