BIOL 3090 - Exam #1 Hart

Chapter One: The Cell Theory

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All living things are composed of?

Cells and their products

All cells come from?

Cells

Cells are essentially alike in?

chemical constitution

The activity of the organism as a whole is the sum of?

the activities and interactions of essentially independent cell units

A cell is the?

fundamental unit of life

A cell is the closest thing to?

autonomous biological units that exist

Autonomous is?

the ability to govern or run itself

All living organism are descended from?

a common ancestor cell

LUCA stands for?

Last Universal Common Ancestor

What diverged from Bacteria?

Eukaryotes and Archaea (thus they are similar)

Cell biology begins with what?

Microscopes to observe cells

Who created these microscopes?

Anton van Leeuwenhoek & Robert Hooke

What's in a cell?

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Prokaryotes are known as?

the SIMPLEST cell

*IMPORTANT CONCEPT: Membranes are separated by?

Compartmentalization

Biological membranes are known as?

compartment barriers

Phospholipids are known as?

Amphipathic (having hydrophilic and hydrophobic parts)

Cholesterol is used for?

rigidity

What are examples of membrane proteins?

receptors, channels, and pumps

Prokaryotes are?

Single-celled organisms that lack a true nucleus

Protists are?

Single-celled organisms with a nucleus

What are the two types of Prokaryotes?

Eubacteria and Archaea

What is Eubacteria?

E. coli & blue-green algae (called cyanobacteria)

What are examples of Archaea?

Grow in harsh environments, such as, halophiles, thermophiles, and methanophiles

Halophile thrive in...

high salt environments

Thermophiles thrive in...

high temperatures

Methanophiles thrive in...

methane high environments because they metabolize it as their carbon and energy source

Methanophiles are killed by?

oxygen; reduce carbon dioxide (CO2) to make CH4 (methane)

Eukaryotes

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Eukaryotes have an?

outer plasma membrane (like prokaryotes)

What is different in eukaryotes than prokaryotes?

eukaryotes have extensive internal membranes (sub-compartments - organelles)

Organelle membranes establish essential environments for specialized functions that must be separated from the?

cytosol

• Compartmentalization

A TRUE nucleus contains?

chromosomes

Functions of organelles:

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Plasma membrane controls?

movement of molecules in and out of the cell and functions in cell-cell signaling and adhesion

Mitochondria are surrounded by a?

Double membrane

What do mitochondria generate?

ATP by oxidation and fatty acids

Endosomes

• intermediate between plasma membrane/trans-golgi and lysosomes

• organizing organelle that transfers material back to plasma membrane or to be degraded by lysosomes

Lysosomes are only in?

ANIMALS

How do they degrade?

autophagy, phagocytosis

Lysosomes have acidic?

lumen (acidic --> acidic hydrolases)

Lysosomes do what?

degrade material internalized by the cell and worn-out organelles

Vacuoles are mostly in?

PLANT cells

What two organelles have similar functions?

lysosomes and vacuoles

Vacuoles are?

large fluid-filled organelles; store nutrients and waste materials; degrade OLD organelles and foreign material

Nuclear envelope is?

double membraned

The nuclear envelope encloses?

contents of the nucleus

What is the OUTER portion of the nuclear envelope continuous with?

rough ER

Nucleolus is the nuclear sub-compartment where most of the cell's?

rRNA is synthesized (ribosome biosynthesis)

Nucleus

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Nucleus is enclosed by an envelope that consists of?

two membranes (nuclear envelope)

The inner membrane is coated with what IN ANIMALS?

nuclear LAMINA

Nuclear pores are on which membrane?

BOTH inner and outer membrane

The nucleus is filled with?

CHROMATIN composed of DNA and proteins

What synthesis takes place in the nucleus?

mRNA and tRNA

What organelles in eukaryotic cells contains DNA?

Mitochondria and Chloroplasts (plants only)

Chlorplasts

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Chloroplasts contain?

inner and outer membranes

What takes place in Thylakoid membranes?

photosynthesis (light and dark reactions)

Chloroplasts converts kinetic energy (sunlight) into?

potential energy (chemical bonds)

What other processes take place in Chloroplasts?

Calvin cycle, ETC, proton gradient, hexose synthesis, ATP synthesis

The STROMA contains?

DNA, RNA, ribosomes

The smooth ER contains enzymes that synthesize?

lipids and detoxify certain hydrophobic molecules (phospholipids)

The rough ER has what three functions?

synthesis, processing, and sorting of secreted proteins (lysosomal & membrane)

The golgi complex processes and sorts?

proteins and lipids that are modified and sent to vesicles

The golgi complex has what three compartments?

cis, medial, and trans sub-compartments

Secretory vesicles store secreted proteins and fuse with?

the plasma membrane to release their contents

Peroxisomes contain enzymes that break down?

long chain fatty acids which are later broken down in the mitochondria

What are peroxisomes in plant seeds?

glyoxisomes

Peroxisomes contain what kind of reactions?

Oxidation --> H2O2m peroxidase

Cytoskeletal fibers form networks and bundles that support membranes by?

organizing and participating in movement

Microvilli increase surface area for?

absorption of nutrients from surrounding medium

The cell wall is made largely of?

cellulose

Cytoskeleton is not a?

membrane-defined organelle, but still very important!

Cytoskeleton is responsible for?

cell shape, strength, and movement

What three things does the cytoskeleton contain to help it perform its functions?

microtubules, intermediate filaments, and microfilaments

Microtubules are

tubulin

Microfilaments are

actin

Intermediate filaments are

IF proteins

Molecules of Life..........

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Molecules -->

Cells -> Tissues -> Organs -> Organisms

75%-80% of a cell's weight consists of?

H2O, salts, sugars, amino acids, nucleotides, and fatty acids (monomers that build up macromolecules)

The rest of the cells weight consists of?

MACROMOLECULES

What are the macromolecules?

Polysaccharides, Proteins, and Nucleic Acids

What is the most common molecule used by cells to capture and transfer energy?

Adenosine triphosphate (ATP)

Proteins

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Proteins are the?

most dynamic of the macromolecules in terms of structure and function

Proteins are made using?

20 amino acids

The average size of a protein is?

53 kDa (400 aa)

If proteins are 400 aa long, how many possible sequences are there?

20^400

A typical eukaryote cell has how many protein molecules?

8*10^9

There are approx. how many different types of proteins?

10,000

Some proteins are

rare (20,000 copies) like receptors for signaling transduction

Some proteins are abundant like

cytoskeleton proteins

Proteins come in different

sizes and shapes

Protein structure determines

protein function

Different Proteins serve different functions

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Enzymes serve as

catalysts like glutamine synthetase

Cell shape comes from

tubulin and actin