Biology lecture exam #2

1-23=Lecture #7

What are the 6 standards of life

organization and complexity

response to environment (homeostasis)

Growth and metabolism

Reproduction and heredity

evolution

composed of one or more cells

Are viruses alive?

No, not in accordance with six standards

What are the two types of cells?

Eukaryotes and Prokaryotes

Prokaryotes include…

Eubacteria and archaea

Eukayotes include…

Animals, plants, fungi and protists

Protists

Any eukaryotes that can’t be defined as a fungi, animal or plant

The most major difference between Eukayotes and Prokaryotes is…

Size

What does cell volume represent?

Demand

What does cell surface area represent?

Supply

As cell size increases…

Cell volume increases faster than SA

Remaining small allows cells to…

Maintain a workable SA:V ratio

Why can some cells live with a large SA?

They have developed adaptations in order to do so

Prokaryotes are the dominant form of life in terms of what?

Diversity and biomass

Prokaryotes differences with eukaryotes

No nucleus (prokaryotes have nucleoids)

No internal membrane system

All prokaryotes have a cell wall

Nucleoid

The area of the cell in which DNA is stored in prokaryotes

Cell wall

A protective outer barrier composed of peptidoglycens that prokaryotes possess

Penicillin

Blocks the formation of peptidoglycan=no cell wall formation=Prokaryotes die

Prokaryotes similarities with eukaryotes

Both have DNA as their genetic material

Both have an outer plasma membrane (phospholipid bilayer)

Both contain cytoplasm

Both have ribosomes

Phospholipid bilayer

Outer plasma membrane in Eukaryotes and prokaryotes

Cytoplasm

a semi-solid substance that contains the cell’s internal components in eukaryotes and prokaryotes

Ribosomes

responsible for synthesizing proteins in eukaryotes and prokaryotes

ALL prokaryotes contain…

Nucleoid

ribosomes

cytoplasm

plasma membrane

cell wall

SOME prokaryotes contain…

Pili

Flagellum

capsule (slime layer)

What is the distinctive feature of a eukaryote?

Internal compartmentalization, possible bc of internal membrane system

What are organelles?

internal membrane-bound compartments serve different purposes

The nuclear envelope

A double lipid bilayer membrane that defines the nucleus (has an inner and outer lipid bilayer)

Outer lipid bilayer of the nuclear envelope

Connected to the smooth and rough ER

Nuclear pores

Passages that pass through the nuclear envelope to regulate nuclear transport

Chromatin

Chromosomal DNA that is bound to DNA binding proteins (located in the nucleus)

The nucleolus (not an organelle)

An area inside the nucleus where ribosomes are assembled

Endomembrane system

A network of internal (lipid bilayer) membranes that include: RER, SER, Golgi apparatus and vesicles

Endoplasmic reticulum structure

Network of interconnected tubules (composed of lipid bilayer), SER and RER are interconnected with each other and the outer lipid bilayer of the nuclear envelope

Space inside tubules of the ER

Lumen

Functions of SER

Site of lipid synthesis, fatty acid desaturation, cholesterol synthesis, and some carbohydrate synthesis

RER function

Proteins are synthesized by RER associated ribosomes,

Proteins synthesized in the RER are either:

Bound for export from the cell

Going to be associated with the outer plasma membrane

Going to be used un the endomembrane system

Where are all other proteins synthesized outside of the ribosome?

In the cytoplasm

Golgi apparatus structure

series of flattened tubes (sacs)

wall of tubes are a lipid bilayer

Not connected to other structures

Cis face of the Golgi apparatus

Receives transport vesicles from ER

Trans face of the Golgi apparatus function

Transports vesicles exit from the Golgi

Function of the Gogli apparatus

Proteins and other molecules may be modified

molecules are sorted by eventual destination

molecules are released in vesicles