Transcript 7th Resource 9-17

Midterm Review
Cell Theory:
- all thing things are composed (made of) cells
- cells are the basic units of structure and function
in living things
- all cells are produced from other cells
- Robert Hooke was the 1st person to see cells
under a microscope, Anton van Leeuwenhoek
was the first person to see a living cell
cell, tissue, organelle, organ, organism,
organ system
cell – the basic units of structure and function in
living things
Tissue – a group of similar cells that work together
to perform a specific function
Organ – made of different kinds of tissues that
function together
Organ system – group of organs that work together
to perform a major function
enzymes – speed up chemical reactions in living
things
Osmosis – the diffusion of water molecules across a
selectively permeable membrane.
Active transport – movement of materials across a
cell membrane using cellular energy.
Passive Transport – the movement of dissolved
materials across a cell membrane without using
energy.
Engulfing – the way food particles are taken in
during endocytosis.
Photosynthesis – cell captures sunlight and uses
it to make food
Light energy + carbon dioxide + water
glucose + oxygen
Cellular Respiration
Glucose + Oxygen
carbon dioxide + water + energy
• Binomial nomenclature – giving each
organism a unique scientific name
For example) humans are homo sapiens
• Element – any substance that cannot be
broken down into simpler substances.
– Example ) carbon, nitrogen, hydrogen, oxygen
• Compound – two or more elements combined
–Example) water H 0
2
• Atom – the smallest unit of an element
The Cell Cycle
Interphase
- The cell grows, makes a copy of its DNA, and
prepares to divide into two cells
- Mitosis – the cell’s nucleus divides into two new
nuclei and one set of DNA is distributed into each
daughter cell.
Mitosis
MITOSIS – 4 stages:
- Prophase :
- Metaphase :
- Anaphase:
- Telophase:
- Cytokinesis:
- the final state of the cell cycle
- the cytoplasm divides
- two new cells are formed
Branching Tree Diagram
- Shows the probable evolutionary relationship
among organisms and the order in which
specific characteristics may have evolved.
Taxonomic Key
- Consists of paired statements that describe the
various physical characteristics of different
organisms.
What do all living things have in
common?
- Have cells
- Contain similar chemicals
- Use energy
- Respond to their surroundings
- grow and develop
- Reproduce
- Homeostasis – cells of organisms are able to
maintain internal stability.
Cells
Prokaryotes
Eukaryotes
• Cells without a
• Cells with a nucleus
nucleus
• Protists
• Bacteria and archaea • Fungi
• Plants
• animals
Parts of a Cell
proteins
vacuole
mitochondria
golgi bodies
nucleus
endoplasmic reticulum
nucleolus
membrane
organelles
Use the words on the previous slide to
fill in the blanks below.
• The ___________________ controls the
materials that enter and leave the cell.
• Ribosomes make ______________.
• The storage area of a cell is called the
______________.
• ___________________ are in the nucleus
where ribosomes are made.
• __________________ receives proteins and
distributes them to other parts of the cell.
Use the words on the previous slide to
fill in the blanks below.
• In the _________________ substances are
produced.
• The ___________________ powerhouse of the
cell; it converts energy stored in food to energy
the cell can use.
• The _________________ is the control center of
the cell.
• _______________________ are tiny cell
structures that carry out specific functions within
the cell.
Animal Cell
nucleus
lysosome
cytoplasm
mitochondria
golgi bodies
cell membrane
ribosomes
endoplasmic reticulum
Name two things a plant cell has that
an animal cell does not have:
cell wall
chloroplasts
Fermentation
Fermentation is an energy releasing process that
DOES NOT require oxygen.
Alcoholic fermentation :
– occurs in yeast and other single –celled
organisms.
- it produces alcohol, carbon dioxide, and a
small amount of energy
ex) making bread, wine, beer
Evolution and Classification
Convergent Evolution – the process by which
unrelated organisms evolve characteristics that
are similar.
ex) birds and insects both use wings to
help them fly
Shared Derived Characteristic
A trait, such as fur, that the common ancestor of
a group had, and passed on to its descendants.
Scientific Name
Scientific Name
genus – a classification grouping that contains
similar closely related organisms
species – a group of similar organisms that can
mated with each other and produce offspring
that can also mate and reproduce.
Chapter 4 Heredity
Heredity – the passing of physical
characteristics from parents to offspring.
Ex) hair color, eye color
Purebred- an organism of many
generations that have the same form for a
trait
Gregor Mendel
• Reasoned that individual factors or sets of genetic
information must control the inheritance of traits
• An organisms traits are controlled by the alleles it
inherits from it’s parents
• Some alleles are dominant, other alleles are
recessive
*** Mendel’s work is historically significant because
it showed that offspring traits are determined by
individual, separate alleles inherited from each
parent ***
Phenotype – an organism’s physical appearance
or visible traits.
Ex) smooth, round, long
Genotype – an organism’s genetic makeup, or
alleles.
Ex) BB, Tt, ss
Homozygous – an organism has two identical
alleles for a trait.
Ex) BB, bb
Heterozygous – an organism has two different
alleles for a trait.
Ex) Bb
Punnett Square – a chart that shows all the
possible ways alleles can combine in a genetic
cross.
Incomplete dominance – occurs when one allele is
partially dominant
Ex) red and white flowers cross to make pink flowers
Codominance – occurs when both alleles for a gene
are expressed equally
Ex)a red fish and blue fish cross and offspring
is a blue and red fish
Multiple Alleles – three or more possible alleles
determine the trait.
Ex) fur in a rabbit
Polygenic Inheritance – occurs when more than one
gen affects a trait
Ex) human height or time it takes for a plant
to flower.
Acquired trait – skills you learn and physical
changes that occur
Ex) calluses, haircuts
Meiosis – the process by which the number of
chromosomes is reduced by half as sex cells
form
Chromosome Theory of Inheritance – genes pass
from parents to offspring on chromosomes.
Chapter 5
• The order of the nitrogen bases along a gene forms a
genetic code that specifies what type of protein will be
produced.
• Proteins are made of amino acids.
• A group of 3 DNA base codes makes up one specific amino
acid.
• The nitrogen bases that pair together are :
• Adenine – Thymine
• Cytosine – Guanine
• Two new daughter cells result when a cell divides. DNA
replication is the process in which an identical copy of a
DNA strand is formed for a new cell.
Mutations
• A mutation is any change in the DNA of a gene
or chromosome.
• Mutations can cause a cell to produce an
incorrect protein during protein synthesis. As
a result, the organism’s trait may be different
from what it normally would be.
• Ex) Cancer is a disease in which the cells grow
and divide uncontrollably, damaging parts of
the body around them.
Sex Chromosomes
• Humans have 23 sex chromosomes.
• The sex chromosomes carry genes that
determine a person’s sex as being either male
or female. They also carry other traits.
• Meiosis – produces sex cells with half the
number of chromosomes
• Mitosis – produces all other body cells
Genetics
Selective Breeding – selecting organisms with desired traits to
be parents of the next generation
Ex) farmers saving seeds from the healthiest plants to
plant the following year
Genetic engineering – genes from one organisms are
transferred into the DNA of another organism
Ex) medicine and improve food crops
Gene therapy – inserting copies of a gene directly into a
person’s cells
Ex) treating hemophilia by replacing the defective X
chromosomes
RNA
• During protein synthesis, the cell uses
information from a gene on a chromosome to
produce a specific protein.
• Two types of RNA take part in protein synthesis:
• MESSENGER RNA – copies the message from
DNA in the nucleus and carries the message to
the ribosome in the cytoplasm.
• TRANSFER RNA – carries amino acids to the
ribosome and adds them to the growing protein.
Evolution
Darwin’s Theory of Evolution – species change
over many generations and become better
adapted to new conditions.
• Natural Selection – the process by which individuals
are better adapted to their environment and more
likely to survive and reproduce more than other
members of the same species.
• Can be based on factors:
• Overproduction
• Variation
• Competition
• Selection
• Environmental change
• Genes and natural selection
Evidence of Evolution
Fossils, patterns of early development, similar
body structures, and similarities in DNA and
protein structures all provide evidence that
organisms have changed over time.
Patterns of Evolution
Gradualism
Species gradually
change over time –
small changes over
time.
Punctuated
equilibrium
Species evolve
during short
periods of rapid
change, and then
don’t change much.
How do new species form?
A new species can form when a group of
individual remains isolated from the rest of its
species long enough to evolve different traits
that prevent reproduction.