Unit 2: Cell Structure and Function

3 principles of cell theory

1. all living organisms are composed of one or more cells, 2. cells are the basic unit of structure and organization of all living organisms, 3. cells arise only from previously existing cells, with the cells passing copies of their genetic material onto their daughter cells

Cell membrane

a thin membrane around the cytoplasm of a cell that controls passage of substances in and out of the cell

Cell wall

strong layer around the cell membrane in plants, algae, and some bacteria

Nucleus

a part of the cell containing DNA and RNA and responsible for growth and reproduction

DNA

deoxyribonucleic acid, the material that contains the information that determines inherited characteristics

Ribosomes

make proteins

Cytoplasm

A jellylike fluid inside the cell in which the organelles are suspended

Chloroplast

plastid containing chlorophyll and other pigments

Plastid-any of various small particles in the cytoplasm of the cells of plants and some animals containing pigments or starch or oil or protein

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production

Vacuole

a tiny cavity filled with fluid in the cytoplasm of a cell

Lysosomes

Breaks down & recycles macromolecules.

Structure of the cell membrane

Consists of a lipid bilayer with proteins embedded throughout. The lipid bilyaer gives tough, flexible structure that forms a strong barrier. Proteins are made of many different kinds of chains of carbohydrates attached to the outer surface of proeins. Proteins form pumps and channels to help materials move into and out of the cell.

Semi-permeable

membranes that allow some substances through but not others

Diffusion

The process by which molecules move from an area of higher concentration to an area of lower concentration

Osmosis

diffusion of molecules through a semipermeable membrane from a place of higher concentration to a place of lower concentration until the concentration on both sides is equal

How is homeostasis related to diffusion and osmosis?

It is related by both trying to maintain an equal environmet throughout. So these two things need to happen in order for that organism to maintain homeotasis.

Hypotonic

(of a solution) having a lower osmotic pressure than a comparison solution

Hypertonic

(of a solution) having a higher osmotic pressure than a comparison solution

Isotonic

(used of solutions) having the same or equal osmotic pressure

ATP

(adenosine triphosphate) main energy source that cells use for most of their work

Why is ATP so important?

it is the chemical form of energy used by all cells

Materials of photosynthesis

carbon dioxide,water,and sunlight

Products of photosynthesis

Glucose(Sugar) and Oxygen

Light Dependent Reactions

reactions of photosynthesis that use energy from light to produce ATP and NADPH

Light Independent Reactions

set of reactions in photosynthesis that do not require light; energy from ATP and NADPH is used to build high-energy compounds such as sugar; also called the Calvin cycle

Sunlight

the main source of energy for life on Earth

Chlorophyll

any of a group of green pigments found in photosynthetic organisms

Chloroplasts

organelles that capture the energy from sunlight and convert it into chemical energy in a process called photosynthesis

Stomata

the small openings on the undersides of most leaves through which oxygen and carbon dioxide can move

Thylakoid

A flattened membrane sac inside the chloroplast, used to convert light energy into chemical energy.

Glucose

C6H12O6 (Sugar)

Oxygen

O2

Carbon Dioxide

CO2

Cellular Respiration

process that releases energy by breaking down glucose and other food molecules in the presence of oxygen

Steps of Cellular Respiration

glycolysis: breakdown of glucose, happens in the cytoplasm and produces 2 ATP. kreb cycle: happens in mitochondria, breaks down pyruvic acid left from glycolysis, produces 2 ATP. electron transport: binds high energy electrons to NAD and FAD to produce ATP from ADP, produces 32 ATP

Aerobic

process that requires oxygen

Anaerobic

process that does not require oxygen

Glycolysis

a metabolic process that breaks down carbohydrates and sugars through a series of reactions to pyruvic acid and release energy for the body in the form of ATP

Kreb's Cycle

second stage of cellular respiration, in which pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions

ETC (Electron Transport Chain)

A series of proteins in which the high-energy electrons from the Krebs cycle are used to convert ADP into ATP.

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production

Materials of Cellular Respiration

Oxygen, glucose; ATP; carbon dioxide, water

Products of Cellular Respiration

Carbon Dioxide, Water, Energy