Topics 1&2 - Cell Structure and Function

Question 1

Learning Objectives

Answer 1

1. Describe the** main concepts of the body**; Inside Vs Outside, Dorsal Vs Ventral, Major body fluid, Layers of Organisational scale, dimentaionality, complexity, dymanic nature of systems and how they operate together
2. Explain major themes organising the human body; scale, concept of SA:V ratio (Examples in lungs and digestive tract)
3. Explain how a single cell can survive and function in isolation
4. Distinguish betweeen the main structures, functions and organelles of a cell.

Question 2

Evolution

Answer 2

“Survival of the fittest”
Organism which is most ‘fit’ for the environment, reproduce most successfully and pass on genes

Question 3

Cell Theory

Answer 3

All organelles are made of cells
Cells are the basis of life
Cells comes from preexisting cells which multiplied

Question 4

Tissues

List the 5 examples

Answer 4

Complex organisational arrangement of cells to fullfill specific functions
- Epithelial
- Connective
- Muscle
- Nervous
- Adipose

Question 5

Organs

Answer 5

Made up of different combinations of tissue types to have a specific function in the body

Question 6

Cells

Answer 6

• Humans consist of cells and water
• Made up of approx. 37 trillion cells

Question 7

Complexity of the Human body

Not important for Syllabus

Answer 7

• Energy supplies
• Scaffolding
• Population systems
• Pumps, ventilation and plumbing
• Purification plant
• Protection
• Control systems
• Create, construct, repair

Question 7

Apoptosis

Answer 7

The programmed ‘death’ of cells as part of development
- Lose approx. 10 a day

Question 8

‘Normal’ levels in the human body

Answer 8

A tight variability is controlled for different important systems
- Body temp
- Salt levels
- Blood glucose levels

Question 9

The balancing of acids and bases

Answer 9

Respiratory system:
- Produces CO2 increasing blood acidity

Metabolic buffers:
- Releases Bicarbonate to raise blood pH and neautralise

Question 10

Surface area to Volume Ratio

Answer 10

Important to sufficiently keep the bodies homeostasis levels equal
- In the lungs, large amnounts of Alveoli allow for maximal efficiency
- In the Digestive Tract and kidneys, large amounts of Villi & Milcrovilli to maximise uptake and diffusion of nutrients

Question 11

Biomolecular innovations

Answer 11

Biomolecules:
- Mapping, engineering and measuring of molecules

Biosystems:
- Engineering of cells, tissues and organs
- Eg. CRISPR technology for genetic modification

Biomechanics:
- Interface between mechanics and biology

Biocomputing:
- Use of cells/ molecules such as DNA for computation.

Question 12

Organells

List and their functions

Answer 12

Nucleus:
- Control centre

Nucleolus:
- RNA transcription site and ribosome biogenesis

Rough ER:
- Ribosome and protein synthesis

Smooth ER
- Lipid and steroid hormone production

Golgi Complex:
- Process proteins from ER into vessicles for transport

Mitochondria:
- Synthesis of ATP
- Has its own DNA and replicates by fission

Lysosomes:
- Acidic organelles for wastre breakdown and disposal

Cytoskeleton:
- Filaments and tubules, gives structure and support, tranport.

Question 13

2 Major types of cells

Answer 13

Prokaryote
- Unicellular organisms

Eukaryote
- Multicellular organisms

Question 14

Orientation

Answer 14

Proximal (towards body on limb)
Distal (Away from body on limb)

Superior/ Cranial (Towards head)
Inferior/ Caudal (Towards floor)

Anterior/ Venrtral (Front of body)
Posterior/ Dorsal (Back of body)

Lateral (Towards side of body)
Medial (Towards midline of body)

Question 15

Liquid in the body

Answer 15

40-45% solids
55-60% fluids

2/3 of fluid of intracellular
1/3 is extracellular

80% of extracellular fluid is interstitual fluid
20% is blood