The Study Of Life

Question 1

Name and define the characteristics of life

Answer 1

Movement: an organisms ability to move a body part or parts

Respiration: the controlled release of energy from food

Nutrition: the way organisms obtain and use food

Reproduction: the ability of an organism to produce new individuals of its own kind and pass on genetic information to the next generation

Organised into Cells: all living things organised into cells - basic unit of life

Growth: to increase in size and development, change in form or shape

Excretion: the removal of waste products of metabolism from an organism

Response: a reaction to a stimulus (change) in the environment

Question 2

Define metabolism and the two types of reactions

Answer 2

Metabolism: the sum of all chemical reactions that occur in the cells of an organism, controlled by enzymes.

Anabolic reactions: small molecules are joined together, forming larger molecules, using energy

Catabolic reactions: large molecules are broken down into smaller molecules, releasing energy

Question 3

What is biological organisation and what is continuity of life?

Answer 3

Biological organisation: Refers to the different levels of complexity of an organism

Continuity of life: The ability of an organism to exist from one generation to the next

Question 4

Define a cell, an organelle, the stains and the two types of cell

Answer 4

• the smallest unit of life that can carry on all the characteristics of life
• structures found incident the cell which carry out a specific function
  Methylene blue: animal

Eukaryote: nucleus, membrane bound organelles in cells eg. human cell

Question 5

Define a cell membrane,
cytoplasm,

Answer 5

CELL MEMBRANE
-Phospholipids bilayer: 2 layers phospholipids, proteins sandwiched in between
- gives cell shape+support, semi-permeable membrane, substances enter by osmosis, active or passive transport

CYTOPLASM:
- Site of all chemical reactions in the cell, consists of cytosol+organelles

Question 6

Define cell wall, mitochondria

Answer 6

• fully permeable composed of polysaccharide cellulose, gives cell strength+support

MITOCHONDRIA
- ‘powerhouse of cell,’ membrane enclosed, non nuclear DNA, provides energy in respiration, large amounts in high energy cells eg. muscle cells

Question 7

Nucleus

Answer 7

NUCLEUS
- involves in cell division, control centre
- Contains DNA found as chromatin (DNA+Protein = chromosomes)
- DNA contains genes for making proteins, which determines the function of the cell
- Nucleuolus makes RNA, used to make ribosomes

Question 8

Ribosomes

Answer 8

Ribosomes are composed of RNA and protein. They function in protein synthesis. They make protein using amino acids. This will be discussed in a later chapter of your text.

Question 9

Golgi Apparatus

Answer 9

Golgi apparatus: produces the membranes that surround the lysosomes,
proteins received from are further processed and sorted for transport to their eventual destinations: lysosomes, the plasma membrane, or secretion

Question 10

Lysosomes

Answer 10

Lysosomes: Lysosomes are membrane-enclosed organelles that contain digestive enzymes capable of breaking down worn out cell parts