unit 5 lesson 1 science

Question 1

function of cell division in unicellular organisms

Answer 1

reproduce+create new mass

Question 2

function of cell division in multicellular organisms

Answer 2

growth, development, repair, reproduction

Question 3

describe DNA

Answer 3

genetic material in cells
contains info+ determines traits living things inherits and need to live
DEOXYRIBONUCLEIC ACID

Question 4

describe chromosomes

Answer 4

chromatin compacted into visible structures
2 chromatin= chromosome

Question 5

label diagram

Answer 5

centromere- middle of DNA X thing
chromatid- part of X thing
chromatin- looks like tin thing mint
protein- inside tin thing
dna- around tin thing

Question 6

define cell cycle and three stages

Answer 6

life cycle of a eukaryotic cell
1. interphase
2. mitosis
3.cytokinesis

Question 7

interphase

Answer 7

stage in cell cycle during which the cell is not dividing

Question 8

four phases of mitosis

Answer 8

prophase- chromosomes condense
metaphase- chromosomes align
anaphase- chromosomes separate
telophase- chromosomes relax

Question 9

chromosome

Answer 9

chromatin compacted into a visible structure

Question 10

mitosis

Answer 10

nucleus divides

Question 11

cytokinesis

Answer 11

division of parent cell cytoplasm

Question 12

DNA of chromosome

Answer 12

one very long double stranded fiber that extends unbroken through the entire length of the chromosome

Question 13

DNA is made up of

Answer 13

a phosphate group, a sugar, and a nitrogen base. the nitrogen bases are adenine, thymine, guanine, and cytosine. adenine always pairs with thymine and cytosine always pairs with guanine.

Question 14

how many chromosomes does a human contain

Answer 14

a human contains 23 pairs of chromosomes one from each parent

Question 15

nucleotides

Answer 15

a human chromosome contains 140 million nucleotides in its DNA. a nucleotide is a subunit of DNA, base sugar and phosphate

Question 16

stages of mitosis

Answer 16

-prophase= in prophase the chromatin in the nucleus condenses into chromosomes. the two pairs of centrioles move to opposite sides of the cell (centrioles are organelles that create basal bodies. basal bodies are where cilia and flagellum attach to the cell body) fibers form between the two pairs of centrioles and attach to the centrosomes. membrane around the nucleus breaks down
-metaphase=chromosome line up in middle of cell
-anaphase= chromatid of chromosome are pulled to opposite sides of cells by fibers attached to centrioles
-telophase=new nuclear membrane forms around each group of chromosomes and they inwind. fiber disappear+cytokinesis begins
-cytokinesis=2 new cells