Animal and Plant Cells: Organelles, Functions, Labelling

17/9/25

Cell Theory

All living things are made up of on or more cells and their products
Cells are the simplest unit that can carry out all life processes
All cells come from other cells

prokaryotes

• pro rhymes with no: no nucleus

• the simplest organism: a single-celled organism

• archaea, bacteria

eukaryotes

• eu rhymes with do: do have a nucellus

• single-celled or multicellular organisms

• protists, fungi, animal and plants

cytoplasm

• the fluid inside cell’s membrane and outside nucleus

• all organelles suspended in cytoplasm

• contains water and cytosol: fluid made of ions and molecules like amino acids, ATP

• site of many chemical reactions

• Give cell its structure

• Where the organelles are located

• allow organelles to move around

cell membrane

• cell plasma membrane

• Phospholipid bilayer containing proteins, cholesterol and carbohydrates

• has a hydrophilic and hydrophobic region

• Separates cell contents from the environment; regulates movement of substances into and out of the cell

• semi-permeable membrane: allows some substances in and keeps others out

• ex. water and oxygen can pass through but larger molecules, like proteins, cannot

nucleus

• Membrane bound spherical structure

• Control centre: contains genetic information that controls all cell activities

• stores genetic information on chromosomes that contain DNA that carries instructions for cell activity

• has chromatin: DNA in a compact dense structure to fit inside nucleus

• DNA is copied when cell divides to ensure each cell has a full set of chromosomes

• surrounded by nuclear envelope/membrane: acts as a physical barrier between nucleus and cytoplasm and allows molecular processes like transport and cell division

mitochondria (singular: mitochondrion)

• Membrane bound, bean shaped

• mostly protein, but also contain lipids, DNA and RNA

• Mitochondrial DNA is passed down from the mother only

• Site of Aerobic Metabolism: breaking down substrate into ATP using oxygen

• Releases energy from food in the form of ATP

• main power source of cell that makes energy available to cell

• active cells, like muscle cells, require more cellular respiration so they have more mitochondria

• less active cells, like fat storage cells, don’t need to respire as quickly so they have less mitochondria

cellular respiration

mitochondria enzymes convert stored energy (glucose) into usable energy, requiring oxygen and creating waste product of carbon dioxide and water

endoplasmic reticulum

• membrane bound channels of tubes and pockets that extend from cytoplasm to nuclear membrane to cell membrane

• transports materials, like proteins, through cells

• assists with production and release of hormones in brain

• involved with muscle contraction in muscles

• composed of rough ER and smooth ER

Golgi body

• also called golgi apparatus and golgi complex

• Flattened, membrane bound, fluid filled disks, with associated vesicles surrounding the disks

• Package proteins, lipids and carbohydrates

• collects and processes materials to be removed from cells

• makes and secretes mucus

• cells that secrete a lot of mucus have a lot of Golgi bodies, like cells in intestine lining

vacoule

• single layer, Membrane bound, fluid-filled sacs

• vacuole surrounded by tonoplast

• Stores starch & water

• supports cell

• In plants, involved in turgor pressure

• animal cells may have many invisible vacuoles

• plant cells usually have a large central vacuole

turgor pressure

pressure exerted by fluid in a cell that presses the cell membrane against the cell wall. A loss of pressure in plant cells causes a loss of water, causing plants to wilt

organelles in plant cells only

• cell wall

• vacuole (singular)

• chloroplasts

ribosomes

• Small spherical bodies free floating in the cytoplasm or attached to ER

• made of RNA and protein

• Site of protein synthesis

• synthesized in the nucelous

lysosomes

• Membrane bound spherical sacs, containing enzymes

• pH of approx. 5

• Site of digestion and storage of digestive enzymes

• Can destroy harmful invaders to the cells

• engulfs and breaks down material (recycling and waste material)

• stores proteins until they are needed inside/outside the cell

• in animal cells

golgi apparatus

process and package protiens and fat molecules

cell wall

• Made of cellulose

• Freely permeable to water and most solutes

• Only in Plant cells

• Maintains cell turgidity

• Provide mechanical support

• Protect from mechanical damage

• found just outside of cell membrane

• can hold together long after plant dies

• used in materials, i.e. textbook paper

singular vacuole

plant cells usually have one main central vacuole
takes up most space in cell
turgor pressure helps keeps plants plump when full of water
cells become soft when turgor pressure drops and leaves and stems becomes limp and droopy until water in replaced

chloroplasts

• in plants and cyanobacteria

• Used for absorption of light

• Site of photosynthesis

• has chlorophyll that gives it green colour

• A series of chemical reactions resulting in the production of glucose and ATP from sunlight and other raw materials

rough endoplasmic reticulum

• apart of ER

• ribosomes attached to outside

• series of canals that carry material throughout the cell

• involved in protein synthesis and transportation of molecules

• protein → hydrophullic

smooth endoplasmic reticulum

• Ribosomes NOT attached to outside

• Makes lipids

• Stores calcium ions

• Transports molecules in the cell

label

1 - nucleus

2 - cytoplasm

3 - cell membrane

label

1 = nucear envelope

2 - nucelus

3 = ribosomes

4 = rough ER

5= smooth ER

label

1 = nucelar envelope

2 = rough er

3 = ribosomes

4 = smooth er

vesicles

• membrane bounds sacs

• transport materials between or within cells

• “mail”

• secretory vesicle: store and transport hormones, neurotransmitters and digestive enzymes

microtubule and microfilament

• protein rich rods

• microtubules: provide internal support

• microfilaments: responsible for contraction of cells for movement of vesicles, granules and cytoplasmic organelles

• centrosome: organizes microtubule cytoskeleten and is the spindle pole for cell division

centriole

• Paired cylindrical structures, made of protein

• Assist in cell reproduction by producing spindle fibres (a type of microfilament)

• Assists in the formation of cilia and flagella

cilia and flagella

• Used for movement

• Cilia are tiny hair-like projections

• Flagella are long tail-like projection

• composed of arranged of microtubules

label

• the nucleus

• 1 = nucleolus

• 2 = nuclear envelope/membrane

• 3 = chromatin

nucleolus

• Dense, spherical structure in nucleus

• composed of DNA, RNA and protein

• Site of ribosome synthesis

nuclear membrane

• phospholipid protein bilayer

• contains nuclear pores: transport between nucleus and cytoplasm and selective passage (small molecules can diffuse more easily than larger ones)

• controls what enters and leaves nucleus

label

nucelar pore

peroxisome

• break down long fatty acid chains and other lipids

• can also participate in synthesis of lilpids

• catalyze oxidation reactions and produce hydrogen peroxide

• then quickly break down H2O2 as they contain catalase

cytoskeleton

• network of protein filaments

• provides structural support

• maintains cell shape

• anchors organelles

• facilitates intracellular transport

• and drives cell movement

plasmodesmata

• channels in cell walls of plant cells

• allow for molecules and substances to move back and forth as needed

differences between plant and animal cells: cell wall, chloroplast, vacoule size, centrosomes, atp

plant cells: have cell wall, have chloroplast, larger vacuole, no centrosomes, atp produced by chloroplast and mitochondria

animal cells: no cell wall, no chloroplast, small vacoule or absent in some cells, has centrosomes, atp produced only by mitochondria

label

• animal cell

• 1 = nucleolus

• 2= nucleus

• 3= chromatin

• 4= smooth er

• 5= nuclear envelope

• 6= vacuole

• 7= nuclear pore

• 8= lysosome

• 9= microtubule

• 10 = ribosome

• 11= rough er

• 12= microfilament

• 13= cytoplasm

• 14= mitochondria

• 15= cell membrane

• 16= centriole

• 17 = golgi body

label

• plant cell

• 1 = smooth er

• 2= plasmodesmata

• 3= mitochondria

• 4= cell wall

• 5= cell membrane

• 6= cytoskeleton

• 7= peroxisome

• 8= vacuole

• 9= chloroplast

• 10 = ribosome

• 11= rough er

• 12= golgi body/apparatus

• 13= vesicles

• 14= nucleolus

• 15= nucleus

• 16= DNA