Unit 3

Cells, Transport, and Energy

Structure

What is it

Function

What does it do

Hypothesis

A prediction based on prior knowledge and observation

Theory

Something shown to be true scientifically multiple times by multiple people

Cell Theory

All living things have one or more cells, all cells are similar in structure and function, all cells come from prexisting cells

2 types of cells in nature

prokaryote and eukaryote

Prokaryote

Simple cell: Contains DNA, ribosomes, and a membrane but has no nucleus or organeles

Eukaryote

Complex cell: contains organelles and nucleus

Organelles

"little organs" perform specific funtions in the cell

Cell membrane

holds organelles in and lets certain material in/out of the cell based on size and concentration
made of phospholipids
is semipermeable

Cell wall (plant cell only)

provides protection and gives structure + support
made of cellulose

Cytoplasm

semi-fluid material that holds organelles in place

Nucleus

controls cells activities, DNA and Nucleolus inside

Nucleolus

produces ribosomes

Nuclear membrane

Lets certain material in/out the nucleus

Ribosomes

synthesizes proteins, can attach to RER

Rough Endoplasmic Reticulum (RER)

Contains ribosomes, transports proteins to the golgi

Smooth Endoplasmic Reticulum (SER)

No ribosomes, synthesizes lipids, transports lipids and hormones to the Golgi

Golgi body

modifies lipids, proteins, and carbs

vesicles

transports material (liquid) into and out of the cell

lysosomes (animal cells only)

breaks down foreign particles in the cell using digestive enzymes

mitochondria

provides the cell with energy by making atp

chloroplasts (plant cells only)

contains pigment called chlorophyll for photosynthesis

centrioles (animal cells only)

cell division

vacuoles

storage of water and nutrients

cell processes

work that is done by organelles in the cells

cell membrane (2)

semi permeable, lets material in/out the cell, made of phospholipids, fluid mosaic model

how is the membrane like a mosaic?

contains many small pieces that make up the entire membrane

Phospholipid shape

hydrophilic head with 2 hydrophobic tails

Other parts of the cell membrane

transport proteins, cholesterol, glycolipids and glycoproteins

Transport proteins

move any material through the membrane based on size and concentration

cholesterol

lipid that supports the membrane

glycolipids and glycoproteins

cell recognition

Enzymes

ex. lipase, protease, lactase, polymerase, all enzymes are proteins, enzymes speed up chemical reactions by lowering amount of energy needed

Enzyme =

ase

enzyme optimums

pH and temperature

Types of transport

passive transport and active transport

passive transport

movement of a material across a membrane from a high to low concentration using NO energy

2 types of passive transport

diffusion and osmosis

diffusion

movement of solutes

solute

any material added to a solvent ex. salt

solvent

usually dissolves or breaks down a solute ex. water

osmosis

movement of water

solution

solute + solvent

Turgor pressure

water pressure found inside a plant cell vacuole

3 types of solutions

hypertonic, hypotonic, isotonic

Isotonic solution

water and solute are in equilibrium and move evenly across the membrane (cell remains the same size)

hypertonic solution

water moves out of the cell through osmosis and solute enters the cell through diffusion (cell shrinks)

hypotonic solution

water moves into the cell through osmosis and solute moves out of the cell through diffusion (cell becomes larger and can even pop) (plant cell is less likely to pop because of the cell wall)

Active transport

movement of material from a low to high concentration across a membrane with energy

2 types of active transport

endocytosis and exocytosis

endocytosis

brings materials into the cell with energy

exocytosis

removes materials from the cell with energy

2 types of endocytosis

phagocytosis and pinocytosis

phagocytosis

brings large particles into the cell

pinocytosis

brings in liquid or small particles to the cell

Energy

The ability to do work

2 types of energy

potential energy and kinetic energy

potential energy

energy at rest

kinetic energy

energy in motion

Energy Laws (Laws of thermodynamics)

1 Law of conservation of energy: energy can not be created/destroyed it can only change forms
2 Law of entropy: in nature things move from order to disorder, it takes energy to maintain order

Types of organisms and how they get energy

Producers and consumers

producers

make their own food, food becomes energy ex. plants - photosynthesis

consumers

get food and energy from an outside source ex. animals - hunt/cook

3 types of consumers

carnivore, herbivore, omnivore

carnivore

eats meat

herbivore

eats plants

omnivore

eats both

science terms for organisms

producer = autotroph, consumer = heterotroph

ATP

molecule that provides energy in all organisms

atp stands for..

adenosine triphosphate

adenosine triphosphate =

adenosine(base) + sugar + 3 phosphates

what organelle in the cell makes atp?

mitochondria

glycolysis

sugar break down

where does energy come from on the atp molecule?

breaking the bond between phosphates 2 and 3 releases energy, the molecule is then renamed
ATP ---> ADP + Pi

ATP Regeneration

How does ADP become ATP?
ATP reforms itself

chemical reactions that involve energy

exothermic reactions and endothermic reactions

exothermic reactions

releases energy

endothermic reactions

takes in energy

energy reactions in organisms

photosynthesis and cellular respiration

Photosynthesis

endothermic reaction, takes in the sun's energy

Cellular respiration

exothermic reaction, releases energy, occurs in the mitochondria

Photosynthesis happens where in the cell?

chloroplasts

chemical reaction for photosynthesis?

6CO2 + 6H2O (in the presence of light) -------> C6H12O6 + 6O2

Reactants

Left of the arrow in the reaction (in photosynthesis: 6CO2 and 6H2O)

Products

Right of the arrow in the reaction (in photosynthesis: C6H12O6 + 6O2)

chemical equation for cellular respiration?

C6H12O6 + 6O2 --> 6CO2 + 6H2O + Energy (ATP)