TEST REVIEW Chapter 12, 13

What are the stages of the CELL cycle and what happens in each? G1: gap period, cell makes proteins and organelles, grows in size S: DNA synthesis; DNA replication occurs G2: gap period 2; metabolic activity occurs, cell gets ready to divide M: Mitotic phase  Includes mitosis: cells divide into 2  And cytokinesis: cytoplasm is divided into 2

How do prokaryotic cells reproduce? By binary fission

What structures contain DNA? chromsomes

Tell me 2 things about asexual reproduction. Only one parent Genetically identical offspring Occurs rapidly How bacteria and prokaryotes reproduce

What is the longest phase of mitosis? Interphase

When are chromosomes replicated? Interphase S phase

What are the fibers containing DNA and proteins called? Chromatin

What holds sister chromatids together? Centromeres

List the 5 stages of mitosis. PPMAT Prophase, prometaphase, metaphase, anaphase, telophase

When do chromosomes become visible? Prophase

When do cells elongate and new nuclei form? telophase

When do chromosomes line up in the middle? metaphase

When do chromosomes begin to separate? anaphase

How do animal cells do cytokinesis? With cleavage furrows

How do plant cells do cytokinesis? With cell plates Vesicles containing cellulose form them

How many daughter cells are made in mitosis? 2

How many daughter cells are made in meiosis? 4

How many pairs of chromosomes in human body cells? 23 pairs, 46 total

Name some diploid cells. Skin, muscle, blood, body cells 2n 23 pairs of chromosomes Somatic cells Zygotes

Name some haploid cells. Egg, sperm n 23 chromosomes Gametes

How many cell divisions in meiosis? 2

What is a gamete? Sex cells Egg or sperm Haploid n Made by meiosis

When does crossing over occur? Prophase I

Why is crossing over important? Genetic diversity, health of populations

Where does meiosis occur? In the ovaries and testes

What is a karyotype Magnified picture of all our chromosomes lined up in pairs

What are somatic cells? Body cells 2n diploid

Telophase is the opposite of what phase? prophase

What are some functions of mitosis? Growth, repair, development, asexual reproduction

What is meiosis? How we make gametes (egg and sperm)

Are somatic cells diploid or haploid? diploid

Are sex cells diploid or haploid? haploid

Reproduction with one parent is… Asexual reproduction

What is a zygote? A fertilized egg Diploid 2n

What causes down syndrome? Trisomy 21 3 chromosomes #21 instead of 2

What is a deletion? When part of the chromosome gets erased during cell divison

What comes before mitosis and meiosis? Interphase

What is a benign tumor? One that doesn’t spread throughout the body

What are the two halves of duplicated chromosomes called? Sister chromatids

What is division of the cytoplasm called? Cytokinesis

How is anaphase of mitosis different than anaphase I? Sister chromatids, not chromosomes, separate

What kinds of chromosomes do sperm have? 22 autosomes 1 sex chromosome, either X or Y They are haploid

How is the cell cycle of cancer cells different? It’s shorter and faster Mitosis happens more

What does meiosis make? Haploid cells Egg and sperm Gametes Genetically different from each other and the parent cells

When does a cell plate form? Telophase

Draw: anaphase, anaphase I, anaphase II

A body cell has 24 chromosomes. Therefore, a sperm from this would have ____. 12

Homologous chromosomes move towards opposite poles during what? Anaphase I

Is a zygote haploid or diploid? diploid

Is a sperm haploid or diploid? haploid

At the end of Meiosis I, how many daughter cells are there? 2

A fly has 8 chromosomes. After mitosis, how many does each new cell have? 8

Does mitosis or meiosis make identical cells? Mitosis

Is a somatic cell haploid or diploid? Diploid

When do chromosomes replicate? S

When does the nuclear membrane break up and microtubules move into place? prometaphase

What forms the cell plate Vesicles With cellulose inside

What is a zygote? The union of a sperm and an egg Happens at fertilization Is diploid, 2n

Where does meiosis occur? In ovaries and testes

What is a chromatid? A replicated chromosome

What is chromatin? DNA and proteins

If there are 10 chromatids in the cell, how many centromeres are there? 5

What is a karyotype? A picture of all the chromosomes in a cell, lined up by size and shape

How much chromosomes and DNA do cells after meiosis have compared to parent cells Half as many chromosomes ¼ the amount of DNA

What is a tetrad? Two sets of sister chromatids that have synapsed (joined)