Bio Midterm

True Or False: A chromatid is made of two identical chromosomes

False

True of False: A chromosome is made of two identical chromatids

True

True of False: There may be thousands of genes on a single chromosome

True

True of False: Female human cells have 23 pairs of homologous chromosomes

True

True of False: The process in which the cell divides is called mitosis

False

True of False: During mitosis, DNA exists as chromatin

False

True of False: During mitosis, DNA exists as a chromosome

True

True of False: A gene contains the instructions to make a protein

True

True of False: Chromosomes form during metaphase

False

True of False: Chromosomes form during prophase

True

True of False: Mitosis is the phase of the eukaryotic cell that occurs after DNA replication and the second growth phase

True

True of False: Sister chromatids are identical

True

True of False: Chromatids separate during anaphase

True

True of False: Chromosomes are coiled structures made of DNA and proteins

True

True of False: Cytokinesis is the final stage of cell division

True

What is a chromosome?

They're coiled structures made of DNA and proteins

What are chromosomes made out of?

They're the foam of the genetic material of a cell during cell division

What are homologous chromosomes?

Two genetically similar chromosomes

How many homologous pairs are in a human cell?

One from each parent, 23

What is the main difference between chromatin and chromosomes?

Chromatin is grainy, and chromosomes are 2 sister chromatids

What is a gene?

A unit of DNA on a chromosome that is encoded with the instructions for a single protein

Why is it necessary for the DNA to replicate prior to cell division?

so that each daughter will have a complete copy of the genetic material

Why do chromosomes have an X-shape

because they are made of two sister chromatids

When do the sister chromatids line up at the equator of the cell?

prophase

During which phase of mitosis do the sister chromatids separate

anaphase

Anaphase

phase of mitosis in which sister chromatids separate and the centromeres divide

centromere

region of the chromosome where sister chromatids are attached

chromatid

two copies of replicated DNA that make a chromosome

chromatin

uncoiled DNA

chromosome

coiled structures made of DNA and proteins

cytokinesis

division of the cytoplasm

gene

a segment of DNA with the genetic instructions to make a protein

metaphase

phase of mitosis in which spindle fibers attach to the centromere of each pair of sister chromatids

prophase

the first and longest phase of mitosis

telophase

phase of mitosis in which the chromosomes begin to uncoil and form chromatin

Chromosomes are coiled structures made of _________ and proteins

DNA

__________ is the division of the nucleus

mitosis

During _________, sister chromatids line up at the equator, or center, of the cell.

metaphase

_________ is the division of the cytoplasm

Cytokinesis

There may be hundreds or even thousands of genes on a single ________________

chromosome

A _________ contains genetic instructions for making proteins

gene

During anaphase, sister _______ separate and the centromeres divide

chromatids

Human cells normally have ______ chromosomes.

46

a new nuclear membrane forms during ____________

telophase

The ___________ fibers ensure that sister chromatids will separate when the cell divides.

spindle

When a chromosome first forms, it actually consists of two sister ______________.

chromatids

Which cells undergo cell division

bacterial cells, broccoli cells, blood cells

Cell division in prokaryotic cells

is relatively simple, results in two daughter cells with identical chromosomes, and is called binary fission

The correct order of phases of the eukaryotic cell cycle is

G1-S-G2-M

Cell division in eukaryotic cells is a complex process betwen

the nucleus

What events may occur during the G1 phase of the cell cycle?

cellular respiration

The cell cycle includes which of the following events

Growth, cell division, DNA synthesis

Why is the cell's DNA copied prior to cell division?

so that each daughter cell will have a complete set of the cells DNA

What is cancer?

a disease that occurs when the cell cycle is no longer regulated

Which cell cycle checkpoint makes the key decision of whether the cell should divide?

the G1 checkpoint

Mitosis ensures that:

each daughter cell receives a complete set of chromosomes

True of False: Cell division in prokaryotes includes mitosis

False

True of False: The cell cycle in prokaryotes includes DNA replication

True

Most prokaryotic cells divide by the process of binary _________

fission

The M phase of the cell cycle includes _________ and cytokinesis

mitosis

The cell cycle in prokaryotes can be described as follows: the cell grows, its _________ replicates, and the cell divides

DNA

During the ______ phase of the cell cycle, the cell's DNA is copied

S

During the M phase, the ________________ and then the cytoplasm divide.

nucleus

Cell division is more complicated in __________ cells than in ___________ cells

eukaryotic, prokaryotic

___________ may result when the cell cycle loses its regulation

cancer

What is the type of cell division that reduces the number of chromosomes in a cell by half?

meiosis

The random distribution of homologous chromosomes during cell division is known as

independent assortment

What type of life cycle do humans have?

a diploid life cycle

Because of when the chromosomes pair up during meiosis, crossing-over must occur during

prophase 1

During which phase of meiosis do homologous chromosomes separate?

anaphase 1

What type of reproduction occurs when a parent cell splits into two identical daughter cells of the same size?

binary fission

What process does not occur between meiosis 1 and meiosis 2

DNA replication

Fertilization in humans produces

diploid zygote

Meiosis begins with one cell, and ends with _________________ cells

4 haploid

Haploid cells contain half the number of _____________ found in other cells of the organism

chromosomes

________________ is the exchange of genetic material during meiosis 1

crossing over

In a diploid life cycle, diploid parents produce __________ gametes

haploid

Asexual reproduction includes binary fission, _________, and ___________

fragmentation, budding

The development of haploid cells into gametes is called __________________

gametogenesis

_______________ reproduction always involves two parents

sexual

_______________ is a type of cell division in which the number of chromosomes is reduced by half

meiosis

True of False: Cell division is basically the same in prokaryotic and eukaryotic cells

False

True of False: Cytokinesis is the division of the cytoplasm

True

True of False: DNA replication results in identical chromosomes

True

True of False: A cell spends most of its life in growth phase 1 of the cell cycle

True

True of False: The S checkpoint, just before entry into S phase, makes the key decision of whether the cell should divide

False

What is the cell cycle?

The series of events that occur in a cell that results in the replication of a cell, producing two new cells

What are the phases of the eukaryotic cell cycle?

Synthesis, interphase, mitotic

In which phase does a cell spend most of its life?

interphase

What happens during interphase?

The cell will grow, perform routine life processes and prepare to divide

What is the S phase?

synthesis phase

What happens in the S phase?

DNA replication

Which cells undergo cell division?

both prokaryotic and eukaryotic cells

Cell division in eukaryotic cells is a complex process because of

the multiple chromosomes, the nucleus, the many organelles

Most routine metabolic processes occur during which phase of the cell cycle?

growth phase 1

The correct order of the eukaryotic cell division is

G1, S, G2, M

The correct order of prokaryotic cell division is

DNA replication, chromosome segregation, cytokinesis

Which cell cycle checkpoint determines whether the DNA has been replicated correctly?

the DNA synthesis checkpoint

What happens during mitosis?

the cell divides

Cell division in prokaryotic cells is called

binary fission