🧬 Biology Review

Compound microscope requirements

Needs a light source and two lenses (ocular and objective lenses)

Robert Hooke

First scientist to identify cells (in cork)

400X magnification

Overall magnification (10x ocular, 40x objective)

Focusing on high power

Use only the fine focus knob to avoid damaging the lens

Cell size from field of view

40 µm or 0.040 mm

Light control on microscope

The diaphragm or the condenser

The nucleus

Control center of the cell

Protein synthesis site

Ribosomes

Powerhouse of the cell

Mitochondria

Function of Golgi bodies

Package cell products to prepare them to move out of the cell

Storage organelles

Vacuole and vesicles

Purpose of cell wall

Provides rigid structure

Site of photosynthesis

Chloroplasts

Organelle that digests old cell parts

Lysosomes

Organelle controlling transport

Cell membrane

Why animals lack chloroplasts

Animals do not produce their own energy

Organelle bacteria lack

Nucleus

Type of cell bacteria are

Prokaryotic

Cells with a true nucleus are prokaryotic

Not a question

Why cell size is limited

Cells must move nutrients and gases across the membrane fast enough to survive

Preferred surface area to volume ratio

High surface area to volume ratio

Active vs passive transport

Active transport requires energy, passive transport does not

Diffusion

Movement of molecules along a concentration gradient

Osmosis

Movement of water along a concentration gradient

Facilitated diffusion

Protein channels help transport molecules without energy

Endocytosis

Movement into the cell by vesicle fusion

Exocytosis

Movement out of the cell by vesicle fusion

Phagocytosis

Movement of large molecules into the cell (cell eating)

Pinocytosis

Movement of small molecules into the cell (cell drinking)

Blood cell in hypotonic solution

Cell swells and may burst

Effect of salt water on plants

Solution is hypertonic; water leaves cells and salt enters killing the plant

Plant cell in isotonic solution

No net movement because concentrations are equal

Homeostasis

Ability of an organism to maintain equilibrium

Equilibrium

Ability of a system to maintain balance

Membrane permeable to sugar and water

Semi-permeable membrane

Sugar movement across membrane

Sugar moves until concentrations are equal

Hydrophilic

Water-loving; phosphate heads

Hydrophobic

Water-hating; lipid bilayer

Cells

Smallest unit of life

Tissues

Groups of cells performing the same function

Organs

Groups of tissues performing similar functions

Organ systems

Groups of organs performing similar functions

Unity and diversity of life

Same life functions but different structures and processes

Unicellular organisms

One cell performs all life functions

Multicellular organisms

Many specialized cells and systems perform life functions

Root system

Located below ground

Shoot system

Located above ground

Dermal tissue function

Exchange of matter and gases

Cuticle

Waxy substance that protects from microorganisms and water loss

Ground tissue function

Support, storage, and photosynthesis

Plant transport structures

Xylem and phloem

Xylem function

Moves water and minerals from roots to stems and leaves

Phloem function

Transports sugars to roots and other parts of the plant

Sieve tube cells

Continuous ducts with no nucleus for transport

Companion cells

Direct activity in themselves and sieve tube cells

Plant gas exchange structures

Stomata and guard cells

Photosynthesis equation

6 CO2 + 6 H2O → C6H12O6 + 6 O2

Cellular respiration equation

C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy

Transpiration

Water leaving the leaf through the stomata

How transpiration works

Evaporation pulls water upward through the plant

Palisade tissue function

Photosynthesis

Spongy mesophyll function

Gas exchange by diffusion

Cohesion

Attraction of water molecules to water molecules

Adhesion

Attraction of water molecules to other substances

Root pressure

Pressure in roots that pushes water upward

Pressure-flow theory

Explains sugar movement through phloem

Tropisms

Plant control systems needed for survival

Phototropism

Growth in response to light

Positive phototropism

Shoots grow toward light

Negative phototropism

Roots grow away from light

Gravitropism

Response to Earth's gravity

Positive gravitropism

Roots grow toward gravity

Negative gravitropism

Stems grow against gravity

Geotropism

Another term for gravitropism