Cell Cycle & Meiosis Quiz

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the main activity of the cell during the G1 phase of interphase?

Growth and preparation of proteins (correct)

Cell division

Error checking of DNA

DNA replication

What does the G in G1 phase stand for?

Growth

Genetic

Gathering

Gap (correct)

Which phase directly follows the G1 phase when the cell has sufficient size and materials?

G0 phase

G2 phase

M phase

S phase (correct)

What is the role of the G2 phase in the cell cycle?

Cell growth and preparation for division Signup and view all the answers

Which statement about cells in the G0 phase is true?

They can transition back to G1 phase upon certain stimuli. Signup and view all the answers

Why might cells like mature heart muscle remain in G0 phase indefinitely?

They rarely receive signals to divide. Signup and view all the answers

What is the outcome of meiosis in terms of chromosome number?

The chromosome number is reduced to half. Signup and view all the answers

During which stage of meiosis are homologous chromosomes separated?

Meiosis I Signup and view all the answers

During which phase of the cell cycle is the DNA content doubled?

S phase Signup and view all the answers

What initiates the transition from G1 phase to the S phase?

Surface area to volume imbalance Signup and view all the answers

What key event occurs during interphase before meiosis begins?

Chromosomes are duplicated. Signup and view all the answers

At the end of meiosis I, how many sister chromatids does each chromosome still consist of?

Two sister chromatids Signup and view all the answers

Which phase of meiosis resembles mitosis?

Meiosis II Signup and view all the answers

What is the total number of haploid cells produced by a single cell that undergoes both meiosis I and meiosis II?

Four haploid cells Signup and view all the answers

What characterizes homologous chromosomes?

They look alike and have the same length and centromere position. Signup and view all the answers

Which statement is accurate regarding meiosis II?

Sister chromatids separate during this phase. Signup and view all the answers

What would happen if sister chromatids separated at the first meiotic division?

The final daughter cells would still be diploid. Signup and view all the answers

Which process promotes genetic diversity during meiosis?

Synapsis and crossing over Signup and view all the answers

What is a consequence of random fertilization?

It generates different zygotes. Signup and view all the answers

How does meiosis affect the chromosome number of gametes?

It reduces the chromosome number by half. Signup and view all the answers

During which phase does independent assortment of chromosomes occur?

Metaphase I Signup and view all the answers

What is the role of chiasmata during meiosis?

They provide the site for crossing over. Signup and view all the answers

What are the three main phases of the cell cycle?

Interphase, nuclear division, cell division Signup and view all the answers

Why is genetic diversity important for species survival?

It allows for adaptation to changing environments. Signup and view all the answers

What is formed when two haploid gametes fuse?

A diploid zygote. Signup and view all the answers

Which phase is primarily involved in the actual division of the cell?

Cell division (cytokinesis) Signup and view all the answers

What occurs during interphase?

The cell duplicates its DNA Signup and view all the answers

How does the length of the cell cycle vary?

It varies based on environmental conditions and cell types Signup and view all the answers

Which subphase is associated with proofreading and repair of DNA?

G2 phase Signup and view all the answers

What can be concluded about the cell cycle and homeostasis?

Cells must reproduce to maintain homeostasis Signup and view all the answers

What does mitosis or meiosis refer to in the context of the cell cycle?

Nuclear division Signup and view all the answers

Onion root tip cells undergo division approximately every how many hours?

20 hours Signup and view all the answers

What is the primary purpose of meiosis in maintaining species identity?

To halve the chromosome number in gametes Signup and view all the answers

What type of cells are generated through meiosis necessary for sexual reproduction?

Haploid gametes Signup and view all the answers

How does meiosis contribute to genetic variation?

By introducing variability through the process of crossing over Signup and view all the answers

What process occurs after the fusion of two haploid gametes during fertilization?

Formation of a diploid zygote Signup and view all the answers

What is the role of meiosis in the plant life cycle?

It produces haploid spores that develop into gametophytes Signup and view all the answers

How does meiosis facilitate the process of speciation?

By generating genetic diversity among isolated populations Signup and view all the answers

What would happen if meiosis did not occur in organisms?

The chromosome count would double with each generation Signup and view all the answers

Which statement about meiosis is true?

Meiosis is responsible for sexual reproduction in eukaryotes Signup and view all the answers

What occurs during prophase of meiosis that does not occur in prophase of mitosis?

Chiasmata formation Signup and view all the answers

In mitosis, how do chromatids behave during the anaphase stage compared to meiosis?

Chromatids separate in mitosis and whole chromosomes in anaphase I of meiosis Signup and view all the answers

How does telophase of meiosis differ from telophase of mitosis?

Telophase of meiosis results in half the number of chromosomes Signup and view all the answers

What characterizes the alignment of chromatids during metaphase in mitosis as opposed to meiosis?

Pairs of chromatids align only in metaphase II of meiosis Signup and view all the answers

Which statement is true regarding homologous chromosomes during prophase of mitosis?

Homologous chromosomes are not visible Signup and view all the answers

What distinguishes cytokinesis in mitosis from meiosis?

Cytokinesis follows two divisions in meiosis Signup and view all the answers

What is the primary outcome of crossing over that occurs in meiosis?

Genetic variation is increased in gametes Signup and view all the answers

During which stage are chromosomes visible in meiosis?

Prophase Signup and view all the answers

Study Notes

8.2: Nuclear Division

The life cycle of a cell consists of three phases:
- Nuclear division (mitosis or meiosis)
- Cell division (cytokinesis)
- Interphase (comprised of G1, S, and G2 subphases)
The length of the cell cycle varies depending on the type of cell and environmental conditions.

8.2.1: The Cell Cycle

The cell cycle is a dynamic process.
Cells reproduce when their surface area can no longer support the volume with nutrients and waste removal.
Interphase is the period between cell divisions involving three phases:
- G1 phase (Gap 1): Cells grow in size, produce RNA, enzymes, and other proteins. This phase can last from several days to years depending on the cell type
- S phase (Synthesis): DNA replication occurs to create enough material for two cells.
- G2 phase (Gap 2): Cells continue to grow and synthesize proteins like tubulin for the mitotic spindle and repair any synthesis errors occurring in S phase.

The Cell Cycle

The cell cycle consists of three phases:
- Interphase
  - G1 phase
  - S phase
  - G2 Phase
- Nuclear Division (mitosis or meiosis)
- Cell Division (cytokinesis)
The cell cycle length varies greatly depending on environmental conditions, cell type, and the organism.

Mitosis

Mitosis is significant in growth, replacement of cells, regeneration, asexual reproduction, and gamete production in plants.
Daughter cells produced via mitosis are genetically identical to the parent cell.
Key phases of mitosis include prophase, metaphase, anaphase, and telophase

8.2.2 Mitosis

Mitosis is a dynamic, continuous process, not discrete steps.
Mitosis is focused on the genetic material of the cell.
Prophase: Chromosomes coil and are distinct; the nuclear envelope disintegrates; centrosomes move apart; the spindle apparatus forms.
Metaphase: Chromosomes align at the metaphase plate.
Anaphase: Sister chromatids separate.
Telophase: Chromosomes decondense; nuclear envelopes reform; chromosomes begin to uncoil; two daughter cells are produced through cytokinesis.

Cytokinesis

Cytokinesis is the division of the cytoplasm to create two daughter cells.
Animal cells: Cytokinesis occurs via a cleavage furrow that progressively pinches the cell into two equal halves.
Plant cells: A cell plate forms to divide the cytoplasm and construct a new cell wall.

Meiosis

Meiosis is a reduction division (2n to n) that produces gametes (sperm and egg cells) or spores.
Meiosis is essential for genetic variation in sexually-reproducing organisms.
Meiosis involves two nuclear divisions which are meiosis I and meiosis II.
Prophase I: Chromosomes condense, homologous chromosomes pair up, crossing over occurs forming chiasmata.
Metaphase I: Homologous chromosomes line up at the metaphase plate.
Anaphase I: Separation of homologous chromosomes, pulling them to opposite poles.
Telophase I & Cytokinesis: Chromosomes unwind partially, cytoplasm divides forming two haploid cells
Prophase II: Chromosomes condense and nuclear envelopes break down (if reforms).
Metaphase II: Individual chromosomes line up at the metaphase plate.
Anaphase II: Sister chromatids separate and migrate towards opposite poles individual chromosomes separate to opposite poles
Telophase II & Cytokinesis: Chromosomes decondense, nuclear envelopes reform. Cytoplasm completely divides forming four haploid cells.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge of the cell cycle, including the G1, S, and G2 phases, as well as the process of meiosis. This quiz covers fundamental concepts such as chromosome behavior, the outcome of meiosis, and the roles of different cell cycle phases. Perfect for biology students looking to reinforce their understanding of cellular processes.