Midterm Flashcards
Mitosis is the stage of the cell cycle during which
the cell’s nucleus divides into two new nuclei.
What happens during cytokinesis in animal cells?
Two new daughter cells are formed.
A DNA molecule is shaped like a
spiral staircase.
Each rung of the DNA ladder is made of
a pair of nitrogen bases.
During what stage of the cell cycle does replication occur?
interphase
What is copied during replication?
the cell’s DNA
What are chromatids?
identical strands of chromosomes
What forms around the chromatids during mitosis?
two new nuclei
The stage of the cell cycle that follows mitosis is called
cytokinesis
The regular cycle of growth and division that cells undergo is called
the cell cycle.
What did Gregor Mendel do to study different characteristics in his genetics experiments?
He cross-pollinated plants.
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?
three 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?
100 percent
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.
The ways in which people change the world around them to meet their needs or solve practical problems are called
technology.
What are some reasonable safety precautions for field investigations?
Be prepared and use common sense.
What is the first thing you should do if an accident occurs?
Notify your teacher.
Knowing how to use lab equipment is an example of
good lab preparations
If a beaker breaks, the first thing you should do is
notify your teacher.
What is the total magnification of a microscope with two lenses when one lens has a magnification of 15, and the other lens has a magnification of 30?
450
How does magnification occur in an electron microscope?
An electron beam creates an image.
Know the parts of the cell theory
Cells are the basic unit of structure and function in living things.
All living things are composed of cells.
All cells are produced from other cells.
What does the term resolution refer to?
how sharp an image is
What is the function of a cell membrane?
to control what enters and leaves the cell
Which organelle is the control center of a cell?
nucleus
What is the function of a cell wall?
to protect and support the cell
The invention of the microscope made it possible for people to discover
cells
Homeostasis refers to an organism’s ability to
maintain stable internal conditions.
What is taxonomy?
the scientific study of how living things are classified
Why do scientists organize living things into groups?
so that the organisms are easier to study
An organism’s scientific name consists of
its genus name and its species name.
The more classification levels that two organisms share,
the more characteristics they have in common.
One characteristic used to place organisms into kingdoms is
their ability to make food.
A plant grows toward the light. The plant’s action is an example of
a response.
Spontaneous generation is a mistaken idea because living things
are produced only by living things.
The source of energy for most autotrophs is
the sun.
All plants are
eukaryotes.
Vascular plants differ from nonvascular plants in
how they transport materials.
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.
A fern’s fronds are
leaves.
What happens in the phloem?
Food moves down from leaves.
Know the parts of a seed
stored food
embryo
cotyledon
Plants that produce seeds
can live in relatively dry environments.
All angiosperms
produce fruits.
A flower’s female reproductive parts are called
pistils.
Know the functions of a plants roots
to absorb water
to store food
to anchor plants
Dormancy is a period when an organism’s growth or activity
stops.
Why are viruses like parasites?
They harm the cells they enter.
Which of the following is found in the cytoplasm of bacterial cells?
genetic material
The best treatment for most viral infections is
bed rest.
How does a vaccine work?
It activates the body’s natural defenses.
Viruses are considered to be nonliving because they
do not show all the characteristics of life.
What directly provides energy for a virus?
its host
