15.4 Ethics and Impacts of
Describe some of the issues that relate to biotechnology.
Identify some of the pros and cons of genetically modified food.
Describe some of the ethical issues relating to biotechno
Why are cells small?
As cell size
much faster than
the surface area.
rid waste through
As cell size increases, a cells ability to exchange with its
Flagella and Cilia - cellular appendages
can propel cells or propel materials over the cell surface
cells that have flagella have few (usually 1 or 2)
cells that have cilia have many - covering the surface
flagella move with whip-like movements to propel
Robert Hooke - 1665 using an early microscope
viewed cork and saw many
structures and called them
What he saw were spaces
surrounded by walls that
once contained living
Since Hookes first observations
what is known about c
Membrane enclosed spaces allow cell functions to be
compartmentalized and isolated from other functions.
Prokaryotes lack membrane enclosed spaces in their cytoplasm.
Some prokaryotes are
for trapping light energy
Where did Eukaryotic Cells come from?
The oldest rocks with evidence of fossil cells date to 3.5 billion
years. The oldest rocks with cells large and complex enough to
be eukaryotic date to 1.0 billion years.
For 2.5 billion years only prokaryotic cells e
have their own DNA, similar to prokaryotic DNA
Can synthesize many of their own proteins using prokaryote-like
Synthesize many, but not all, of their own proteins
Replicate through division similar to prokaryotic cell division
Ribosomes - protein
two subunits - large and
small - each made of
protein and ribosomal
subunits associate when
they are synthesizing
protein synthesis occurs
on ribosomes that are
free-floating in the
Cytoskeleton - scaffolding of proteins that transport materials,
position and move organelles, maintain and change cell shape,
and organize enzymes into functional associations
3 components - actin filaments, microtubules, and
Mitochondria and chloroplasts appear to be the direct
descendants of energy producing bacteria. Mitochondria are the
descendants of bacteria that were capable of oxidative respiration.
Chloroplasts are the descendants of photosynthetic bacteria.
Bacteria often have flagella with a single protein core (flagellin)
that they can use to move in a rotary corkscrew like fashion
The rotary motor
through the cell
Challenged the idea that life forms are unchanging
Noted similarities between humans and apes
Believed earth was older than 6000 years
Fossils are specimens preserved in amber, permafrost, dry caves and rocks
The interior contents of cells is the cytoplasm. The cytoplasm is
isolated from the surrounding environment by the _ _ .
There are two fundamentally different forms of cells.
_ cells relatively simple cells - lack
nuclear membrane and many
organelles - ba
The Golgi Apparatus also forms lysosomes
Lysosomes - vesicles filled with digestive enzymes - used for
Particles can be
taken into cell
and vesicle fused
of organelles can
be recycled af
Golgi Apparatus a collection of membranes associated with the ER
composed of flatten sacs called _
concentrates and packages proteins synthesized on the ER
The Golgi is functionally associated with the ER.
Plants have cell walls made of cellulose.
During cell division plant cells build dividing walls between the
two new cells called the cell plate. An adhesive layer - the
middle lamella - is laid down between the new cell walls
Cell walls can be thickened t
has basal body with 9 + 0
structure of microtubules
flagellum is membrane
bound with pairs of
microtubules in a 9+2
each pair of tubules has
short arms of another
protein - dynein that extend to
movement of the flagel
Microbodies: Peroxisomes and Glyoxisomes
vesicles that form through growth and division within the
Glyoxisomes are found in plants - contain enzymes that convert
fats into carbohydrates
Peroxisomes - used for
compounds from the
Centrioles - are part of specialized region of the cell called the
centrosome (cell center)
found in animals and most protists
the centrioles are involved in the
production of microtubules
microtubules have many functions
including moving chromosomes
Mitochondria The site of oxygen consumption within cells
Have their own DNA that is similar to prokaryotic DNA
Have their own ribosomes that are similar in construction to
Synthesize many, but not all, of their own proteins
actin filaments - involved in cell movements and in membrane
deformations - smallest components of the cytoskeleton
microtubules - hollow tubes made of proteins called tubulins
responsible for cell movements and movements of organelles
within the cytoplas
Chloroplasts - sites of photosynthesis - in nearly all plants and
trap light energy and convert it into chemical energy
have double membrane structure - inner space is the stroma
Within the stroma
have a series of
stacks of flattened
Chromosome - colored body
consists of both DNA and protein - seen as chromosomes when
highly condensed in preparation for cell division
At other times the DNA and
protein are threadlike and
The most common proteins
are histones. DNA is coiled
2.3 Chemical Communication by Hisrich
2.3.a What is a hormone?
A hormone is a chemical (specifically a protein)
secreted by an endocrine gland (gland is just a
name for an organ that secretes something) that
signals a system to do something.
2.4 Communication with the Outside World Study Guide by Hisrich
2.4.a. How do humans communicate with the world around them?
Humans take in information using their senses (sight, hearing, touch, taste & smell) & send out information using
their ability to
2.2 Electrical Communication Study Guide by Hisrich
2.2.a How does communication happen within the body?
Electrical Signals Nervous System
Chemical Signals Endocrine System
The nervous system is made up of neurons. Neurons communicate just like people do,
2.1 The Brain Study Guide by Hisrich
2.1.a. What is communication?
Communication is messages passing from one entity to another & being understood by the 2nd entity.
2.1.b. What are ways communication occurs in machines and in the human body?
SC/CHEM 1500 4.0
INTRODUCTION TO CHEMISTRY
Lecture 3: Chemistry Measurement
is a quantitative science
deals with the measurement
of substance properties
Unit of Measurement
Unit of measurement