L1 - Introduction to Cell Biology

Question 1

What are the 7 processes of life?

Answer 1

• Movement
• Respiration
• Sensitivity
• Growth
• Reproduction
• Excretion
• Nutrition

Question 2

What are neurones?

Answer 2

Nerve cells that process and transmit information through electrical and chemical signals.

Question 3

Give 3 examples of movement in living organisms.

Answer 3

• Plant cells can move towards light (phototropism)
• Bacterial and sperm cells ‘swim’ using a flagellum
• Blood cells (neutrophils) chase bacteria before engulfing

Question 4

What is the equation for cellular respiration?

Answer 4

C6H12O6 + 6O2 → 6H2O + ATP

Question 5

What are the 2 types of respiration?

Answer 5

• Cellular Respiration

- Physiological Respiration

Question 6

Describe the difference between cellular respiration and physiological respiration.

Answer 6

• Cellular respiration is the process of oxidising organic food molecules (glucose) to carbon dioxide and water.
• Physiological respiration is the movement of O2 from outside environment to cells within tissue; and transport of CO2 in the opposite direction.

Question 7

What is meant by sensitivity, in reference to living organisms?

Answer 7

Living things can detect and respond to changes in the environment.

Question 8

What is meant by growth, in reference to living organisms?

Answer 8

Foetal growth and an onwards increase in size, maturity and complexity.

Question 9

Describe briefly how reproduction occurs in animals, and its importance.

Answer 9

• Genetic information in the nucleus is replicated.
• Mitosis: Cell can divide to form 2 identical daughter cells.
• Allows cells in tissues to divide for growth and repair.

Question 10

Why are nutrients important for sustaining life?

Answer 10

Provide the raw materials for energy to fuel life processes, growth and repair.

Question 11

Why is excretion important for sustaining life?

Answer 11

Chemical processes essential for life produce toxic / unwanted waste which must be excreted.

Question 12

Name the 3 organelles present in both animal and plant cells. Describe their roles.

Answer 12

• Nucleus: control centre, contains genetic information in the form of DNA
• Cytoplasm: gel-like mix in which biochemical reactions occur
• Plasma Membrane (around cell): functions as a selective barrier, controls movement of materials in and out of cell.

Question 13

Name the 3 organelles present in plant cells. Describe their roles.

Answer 13

• Rigid cell wall: (composed of cellulose fibres) provides cell with strength, structure and protection
• Large vacuole (fluid-filled space / vesicle in cytoplasm, enclosed by membrane): helps to maintain cell turgor, responsible for storage / movement of substances
• Chloroplasts: contain chlorophyll (green pigment) which is used in photosynthesis

Question 14

What is photosynthesis

Answer 14

Use of sunlight to synthesise nutrients from CO2 + H2O with release of O2.

Question 15

Describe the 8 levels of organisation.

Answer 15

1) Chemical components (atoms, molecules)
2) Cell components (organelles)
3) Cells
4) Tissues
5) Organs
6) Organ system
7) Organism
8) Population

Question 16

What are tissues?

Answer 16

A collection of interconnected cells that work together to perform a similar function.

Question 17

What are organs?

Answer 17

A group of tissues in living organisms adapted to perform a specific function.

Question 18

What are organ systems?

Answer 18

A group of organs that work together to perform one or more functions.