Cell Cell OverviewOverview

Answer all “Think” prompts on the left side of your notes.

The cell

• Cells are highly Cells are highly organized collections organized collections of molecules.of molecules.

• Cells are basic unit Cells are basic unit of structure and of structure and function of life.function of life.

Think: the cells in the bottom picture are human blood cells. Why don’t they all look the same?

– Robert HookeRobert Hooke (1665) (1665) observed cell walls of cork observed cell walls of cork cells.cells.

– Leeuwenhoek Leeuwenhoek (1673) (1673) first irst living cells observed.living cells observed.

Discovery of the cellDiscovery of the cell

Robert HookeRobert Hooke

Anton van Anton van LeeuwenhoekLeeuwenhoek

Leeuwenhoek’s MicroscopeLeeuwenhoek’s Microscope

• All living things are All living things are composed of one or composed of one or more cells.more cells.

• Cells are the basic Cells are the basic unit of structure & unit of structure & function.function.

• Cells come only Cells come only from the from the reproduction of reproduction of existing cells.existing cells.

Cell theoryCell theory

Nucleus of elodea cellNucleus of elodea cell

Think: what does it mean to be the basic unit of structure and function? Why are these 2 things connected?

• Prokaryotic cellsProkaryotic cells– Most primitive cellMost primitive cell– Evolved 3.9 Billion years agoEvolved 3.9 Billion years ago– Cells before organized nucleus.Cells before organized nucleus.– Bacteria (anaerobic Bacteria (anaerobic

respiration)respiration)

• Eukaryotic cellsEukaryotic cells– Complex cellsComplex cells– Evolved 2.5 BYAEvolved 2.5 BYA

– All multicellular organisms have this type (aerobic respiration)

Two cell types

EukaryoticEukaryotic

ProkaryotiProkaryoticc

Think: ‘Pro ‘means 1st. How will this help you remember which kind of cell is which?

• Highly variable in size and shape.Highly variable in size and shape.• Structure is adaptation to function.Structure is adaptation to function.

• The shape of a cell is determined by its jobThe shape of a cell is determined by its job

• Limitations on sizeLimitations on size– Surface area to volume ratio.Surface area to volume ratio.

Cell Diversity

Think: Think of some eating utensils. What are their structures and functions?

• A cell membrane AKA A cell membrane AKA plasma membraneplasma membrane

• Cytoplasm Cytoplasm – The jelly-like substance The jelly-like substance

that the organelles float that the organelles float inin

• Ribosomes Ribosomes – Produce proteinsProduce proteins

• DNADNA– The genetic informationThe genetic information

All cells have All cells have

Plant Cell Vs Animal Cell

Plants have three types of Plants have three types of organelles that animals organelles that animals lack.lack.

– Chloroplasts• Photosynthesis

– Central vacuole• Storage & structure

– Cell wall• Support structure• Animal cells are the only

cells w/out a cell wall

Typical Plant Typical Plant CellCell

In a paragraph answer the following in your summary

1. What is the simplest type of cell?

2. What are the components of cell theory?

3. What do all cells have?

4. Name 3 ways plant cells are different than animal cells.