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Flashcards in Midterm Deck (65)
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1
Q

Mitosis is the stage of the cell cycle during which

A

the cell’s nucleus divides into two new nuclei.

2
Q

What happens during cytokinesis in animal cells?

A

Two new daughter cells are formed.

3
Q

A DNA molecule is shaped like a

A

spiral staircase.

4
Q

Each rung of the DNA ladder is made of

A

a pair of nitrogen bases.

5
Q

During what stage of the cell cycle does replication occur?

A

interphase

6
Q

What is copied during replication?

A

the cell’s DNA

7
Q

What are chromatids?

A

identical strands of chromosomes

8
Q

What forms around the chromatids during mitosis?

A

two new nuclei

9
Q

The stage of the cell cycle that follows mitosis is called

A

cytokinesis

10
Q

The regular cycle of growth and division that cells undergo is called

A

the cell cycle.

11
Q

What did Gregor Mendel do to study different characteristics in his genetics experiments?

A

He cross-pollinated plants.

12
Q

Factors that control traits are called

A

genes.

13
Q

Scientists call an organism that has two different alleles for a trait a

A

hybrid.

14
Q

What does the notation TT mean to geneticists?

A

two dominant alleles

15
Q

What does the notation Tt mean to geneticists?

A

one dominant allele and one recessive allele

16
Q

What is probability?

A

a number that describes how likely it is that an event will occur

17
Q

What is the probability of producing a tall pea plant from a genetic cross between two hybrid tall pea plants?

A

three in four

18
Q

What does a Punnett square show?

A

all the possible outcomes of a genetic cross

19
Q

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?

A

100 percent

20
Q

An organism’s physical appearance is its

A

phenotype.

21
Q

Which term refers to physical characteristics that are studied in genetics?

A

traits

22
Q

The different forms of a gene are called

A

alleles.

23
Q

An organism’s genotype is its

A

genetic makeup.

24
Q

An organism that has two identical alleles for a trait is

A

homozygous.

25
Q

A heterozygous organism has

A

two different alleles for a trait.

26
Q

The ways in which people change the world around them to meet their needs or solve practical problems are called

A

technology.

27
Q

What are some reasonable safety precautions for field investigations?

A

Be prepared and use common sense.

28
Q

What is the first thing you should do if an accident occurs?

A

Notify your teacher.

29
Q

Knowing how to use lab equipment is an example of

A

good lab preparations

30
Q

If a beaker breaks, the first thing you should do is

A

notify your teacher.

31
Q

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?

A

450

32
Q

How does magnification occur in an electron microscope?

A

An electron beam creates an image.

33
Q

Know the parts of the cell theory

A

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.

34
Q

What does the term resolution refer to?

A

how sharp an image is

35
Q

What is the function of a cell membrane?

A

to control what enters and leaves the cell

36
Q

Which organelle is the control center of a cell?

A

nucleus

37
Q

What is the function of a cell wall?

A

to protect and support the cell

38
Q

The invention of the microscope made it possible for people to discover

A

cells

39
Q

Homeostasis refers to an organism’s ability to

A

maintain stable internal conditions.

40
Q

What is taxonomy?

A

the scientific study of how living things are classified

41
Q

Why do scientists organize living things into groups?

A

so that the organisms are easier to study

42
Q

An organism’s scientific name consists of

A

its genus name and its species name.

43
Q

The more classification levels that two organisms share,

A

the more characteristics they have in common.

44
Q

One characteristic used to place organisms into kingdoms is

A

their ability to make food.

45
Q

A plant grows toward the light. The plant’s action is an example of

A

a response.

46
Q

Spontaneous generation is a mistaken idea because living things

A

are produced only by living things.

47
Q

The source of energy for most autotrophs is

A

the sun.

48
Q

All plants are

A

eukaryotes.

49
Q

Vascular plants differ from nonvascular plants in

A

how they transport materials.

50
Q

You would expect to find spores

A

on the underside of fern fronds.

51
Q

The part of a moss that absorbs water and nutrients from the soil is the

A

rhizoid.

52
Q

A fern’s fronds are

A

leaves.

53
Q

What happens in the phloem?

A

Food moves down from leaves.

54
Q

Know the parts of a seed

A

stored food
embryo
cotyledon

55
Q

Plants that produce seeds

A

can live in relatively dry environments.

56
Q

All angiosperms

A

produce fruits.

57
Q

A flower’s female reproductive parts are called

A

pistils.

58
Q

Know the functions of a plants roots

A

to absorb water
to store food
to anchor plants

59
Q

Dormancy is a period when an organism’s growth or activity

A

stops.

60
Q

Why are viruses like parasites?

A

They harm the cells they enter.

61
Q

Which of the following is found in the cytoplasm of bacterial cells?

A

genetic material

62
Q

The best treatment for most viral infections is

A

bed rest.

63
Q

How does a vaccine work?

A

It activates the body’s natural defenses.

64
Q

Viruses are considered to be nonliving because they

A

do not show all the characteristics of life.

65
Q

What directly provides energy for a virus?

A

its host