IB Biology SL Unit 1

Functions of Life: MR SHENGE

Functions of Life: MR SHENGE

Metabolism, Reproduction, Sensitivity, Homeostasis, Excretion, Nutrition, Growth, Evolution

Metabolism

Sum of chemical reactions, responsible for all actions

Reproduction

Sexual: 2 parents, offspring is unique, fusion of haploid sex cells, meiosis Asexual: 1 parent, offspring is identical, mitosis and binary fission

Sensitivity and Response

All life responds to changes in environment

Homeostasis

Keeps internal environment within the range of stable internal conditions despite external environments

Excretion

Metabolic waste is eliminated

Nutrition

Autotrophs: Normally plants, abiotic source into chemical energy Heterotrophs: Chemical energy found in matter

Growth and Development

Growth: Size and mass change Development: Transformation over lifespan

Evolution and Adaptation

Evolution: Ratio of different genetic types change Revolution: Fitted to environment

Paramecium Metabolism

Cytoplasm contains dissolved enzymes, digestion

Paramecium Reproduction

Mitosis, asexually

Paramecium Sensitivity

Cilia to move

Paramecium Nutrition

Eats smaller unicellular organisms, heterotroph, eats YEAST

Paramecium Homeostasis

Contractile Vacuole, swells and expels water through opening in cell membrane

Paramecium Excretion

Anal pore

Chlamydomona Metabolism

Cytoplasm and Chloroplast contains dissolved enzymes, digestion, photosynthesis, cellular respiration

Chlamydomona Reproduction

Asexual, mitosis

Chlamydomona Sensitivity

Eye spot to sense light and 2 flagella to move around

Chlamydomona Nutrition

Autotroph, photosynthesis

Chlamydomona Homeostasis

Contractile Vacuole, swells and expels water

Chlamydomona Excretion

Oxygen deposited from photosynthesis through cell membrane

Levels of biological organization

Atom Simple molecules Macro molecules Sub cellular structures Cells Tissues Organ Organ system Organism Population Community Ecosystem Biome Biosphere

Emergent Properties

Property that comes from parts interacting with the whole

Cell Theory

1. Cell is the basic unit of life

2. All living things are made of cells

3. Cells come from preexisting cells

Evidence of Cell Theory

1. Sub cellular cannot perform functions of life

2. Tissues of plant and animal contains at least 1 cell

3. Never observed spontaneous generation

Implications

1. Trace origin of cells in our body back to zygote

2. First cell can be traced back to evolution of LUCA

3. 1st cell must've come from non-living material

Trend

Prevailing tendency, generalization Leads to development of predictions

Discrepancy

Doesn't fit the trend Lead to scientific questions

Trends in Cells

Cells are small All living things are made of cells

Discrepancies in Cells

Red Blood Cells- No nucleus or mitochondria Giant Algae- Big single celled organism Skeletal Muscles- More than 1 nucleus Fungal Hyphae- Not made of clear, individual cells

Development of Cell Theory

Jansen- Compound microscope Hooke- Discovered cells Leeuwenhock- Discovered unicellular Schleiden- All plants are made of cells Schwann- All animals are made of cells Vichow- All cells come from other cells Abbe & Zeiss- Modern compound microscope Scanning electron microscope