Mid term 15-16 Flashcards
What are the products of photosynthesis?
oxygen and sugars
What happens during photosynthesis?
The cell uses the energy in sunlight to make food.
How does photosynthesis benefit heterotrophs?
It creates food that they can eat.
What captures energy from sunlight during photosynthesis?
chlorophyll and other pigments
All organic compounds contain the element
carbon.
Why is water important for a cell?
Most chemical reactions in cells require water.
Which term refers to the movement of molecules from an area of higher concentration to an area of lower concentration?
diffusion
Which term refers to the diffusion of water molecules through a selectively permeable membrane?
osmosis
Which term refers to the movement of materials through a cell membrane without using the cell’s energy?
passive transport
Enzymes are important because they
speed up chemical reactions.
Sugar molecules can combine with one another to form large molecules called
starches.
When two or more elements combine chemically, they form a(n)
compound.
A species is a group of similar organisms that
can mate with each other and produce fertile offspring.
What did Darwin infer from his observations of organisms in South America and the Galápagos Islands?
A small number of different plant and animal species had come to the Galápagos Islands from the mainland.
Differences between members of the same species are called
variations.
Which of these is one of the main ways that a new species forms?
A group is separated from the rest of the species.
What are fossils?
the preserved remains or traces of organisms that lived in the past
How do most fossils form?
A dead organism becomes buried in sediment.
How do scientists determine the actual age of fossils?
radioactive dating
Which term refers to a species that no longer has any living members?
extinct
What theory proposes that evolution occurs steadily in tiny changes over long periods of time?
gradualism
What theory agrees with fossil records that show no intermediate forms for long periods of time?
punctuated equilibria
Which term refers to similar structures that related species have inherited from a common ancestor?
homologous structures
If two organisms look very similar during their early stages of development, this is evidence that the organisms
evolved from a common ancestor.
Scientists combine evidence from fossils, body structures, early development, DNA, and protein structures to
determine the evolutionary relationships among species.
What did Darwin observe about finches in the Galápagos Islands?
Their beaks were adaptations related to the foods the finches ate.
The gradual change in a species over time is called
evolution.
A trait that helps an organism survive and reproduce is called a(n)
adaptation
Which term refers to the process by which individuals that are better adapted to their environment are more likely to survive and reproduce?
natural selection
Which term refers to a species creating more offspring than can possibly survive?
overproduction
How does natural selection lead to evolution?
Helpful variations accumulate among surviving members of the species.
Factors that control traits are called
genes.
Scientists call an organism that has two different alleles for a trait a
hybrid
What does the notation TT mean to geneticists?
two dominant alleles
What does the notation Tt mean to geneticists?
one dominant allele and one recessive allele
What is probability?
a number that describes how likely it is that an event will occur
What is the probability of producing a tall pea plant from a genetic cross between two hybrid tall pea plants?
____?____ in four
What does a Punnett square show?
all the possible outcomes of a genetic cross
If a homozygous black guinea pig (BB) is crossed with a homozygous white guinea pig (bb), what is the probability that an offspring will have black fur?
You will have to figure this one out on your own
An organism’s physical appearance is its
phenotype.
Which term refers to physical characteristics that are studied in genetics?
traits
The different forms of a gene are called
alleles.
An organism’s genotype is its
genetic makeup.
An organism that has two identical alleles for a trait is
homozygous
A heterozygous organism has
two different alleles for a trait.
All plants are
eukaryotes.
Vascular plants differ from nonvascular plants in
how they transport materials.
What parts of a fern grow underground?
roots and stems
You would expect to find spores
on the underside of fern fronds.
The part of a moss that absorbs water and nutrients from the soil is the
rhizoid.
