Biology Ch1

Question 1

What is the basic structural unit of a chromosome?

Answer 1

A chromatid.

Question 2

True or False: Chromosomes are only visible during cell division.

Answer 2

True.

Question 3

What are the two main types of chromosomes?

Answer 3

Autosomes and sex chromosomes.

Question 4

Fill in the blank: Chromosomes are made up of ________ and proteins.

Answer 4

DNA.

Question 5

What is the process called where the cell divides to form two daughter cells?

Answer 5

Cell division.

Question 6

What are the phases of the cell cycle?

Answer 6

Interphase and mitotic phase.

Question 7

Which phase of the cell cycle is the longest?

Answer 7

Interphase.

Question 8

What occurs during the S phase of interphase?

Answer 8

DNA replication.

Question 9

True or False: Mitosis results in four daughter cells.

Answer 9

False.

Question 10

What is the main purpose of mitosis?

Answer 10

To produce two genetically identical daughter cells.

Question 11

What is the name of the structure that holds sister chromatids together?

Answer 11

Centromere.

Question 12

During which phase of mitosis do chromosomes align at the cell’s equator?

Answer 12

Metaphase.

Question 13

Fill in the blank: The period of cell growth before mitosis is called ________.

Answer 13

Interphase.

Question 14

Which stage of the cell cycle includes G1, S, and G2 phases?

Answer 14

Interphase.

Question 15

What is cytokinesis?

Answer 15

The division of the cytoplasm into two daughter cells after mitosis.

Question 16

True or False: Chromosomes are composed of RNA.

Answer 16

False.

Question 17

What is the function of telomeres?

Answer 17

To protect the ends of chromosomes from deterioration.

Question 18

In which phase do the nuclear envelope and nucleolus reappear?

Answer 18

Telophase.

Question 19

What is the term for the physical location of a gene on a chromosome?

Answer 19

Locus.

Question 20

Which type of cell division is used for growth and repair?

Answer 20

Mitosis.

Question 21

What are homologous chromosomes?

Answer 21

Pairs of chromosomes that are similar in shape, size, and genetic content.

Question 22

Fill in the blank: During ________, the cell prepares for mitosis.

Answer 22

G2 phase.

Question 23

How many chromosomes do humans have?

Answer 23

46 chromosomes.

Question 24

What is a karyotype?

Answer 24

A display of an individual’s complete set of chromosomes.

Question 25

During which phase do sister chromatids separate?

Answer 25

Anaphase.

Question 26

True or False: A diploid cell has two sets of chromosomes.

Answer 26

True.

Question 27

What are Chromatin Fibres?

Answer 27

Chromatin fibres are complex made of DNA (40%) and histones (60%).

Question 28

What is the basic unit of chromosome?

Answer 28

DNA/ Nucleosome

Question 29

What is a chromatid ?

Answer 29

Similar longitudinal half of a chromosome.

Question 30

What is a nucleosome ?

Answer 30

A complex made of 8 histone molecules wound around by a strand of DNA.

Question 31

What is structure of DNA called ?

Answer 31

Double Helical Structure

Question 32

Who and when proposed the double helical structure of a DNA ?

Answer 32

James Watson and Francis Crick (1953)

Question 33

How many RBC’s are destroyed per minute?

Answer 33

20 million

Question 34

What is the lifespan of RBC’s ?

Answer 34

120 Days

Question 35

What is the basic unit of DNA ?

Answer 35

Nucleotide

Question 36

What kind of a molecule is DNA ?

Answer 36

Macromolecule

Question 37

What kind of molecules are DNA and a nucleotide ?

Answer 37

DNA: Polymer Nucleotide: Monomers

Question 38

Why do we need Mitosis?

Answer 38

Growth, Repair, Replacement

Question 39

Why do we need meiosis ?

Answer 39

Production of Gametes

Question 40

What do you mean by haploid number of chromosomes ?

Answer 40

Half the number of chromosome as compared to diploid. It is represented by n while diploid by 2n.

Question 41

Meiosis leads to the formation of _________ daughter cells.

Answer 41

Four

Question 42

A zygote or fertilised egg has _______________ number of chromosomes.

Answer 42

Diploid (Half from each parent)

Question 43

What is a neuclotide composed of ?

Answer 43

Deoxyribose Sugar, Nitrogenous Base and Phosphate

Question 44

What shape does a DNA molecule for if we open its two strands?

Answer 44

A ladder

Question 45

What forms the rungs of the ladder ?

Answer 45

Nitrogenous Base

Question 46

What forms the backbone of DNA molecule ?

Answer 46

Phosphate Group

Question 47

What is the other name of the deoxyribose sugar found in a DNA ?

Answer 47

Pentose Sugar

Question 48

The nitrogenous base only found in RNAis Cytosine, (True/False)

Answer 48

False Correct Answer: Uracil

Question 49

The two types of nitrogenous bases are_______________ and ______________.

Answer 49

Purines and Pyrimidines

Question 50

Name the Purines.

Answer 50

Adenine and Guanine

Question 51

Complete the statement: Adenine only pairs with ________________________

Answer 51

Thymine in DNA and Uracil in RNA.

Question 52

The type of bond found between two nitrogenous bases is ______.

Answer 52

Hydrogen Bond

Question 53

Cystosine is paired with _________ with ________ hydrogen bond

Answer 53

Guanine, triple

Question 54

Double hydrogen bond is found between ?

Answer 54

Adenine an Thymine (DNA) Adenine and Uracil (RNA)

Question 55

Mitosis is als known as ___________ _____________ .

Answer 55

Equational Division

Question 56

The DNA molecule is __________(acidic/alkaline) and (positive/negative).

Answer 56

acidic, negative

Question 57

Two Stands of DNA are ____________ (parallel/ anti-parallel).

Answer 57

Anti-parallel

Question 58

What is gene?

Answer 58

A specific sequence of Nucleotide on a chromosome.

Question 59

What do you mean by ‘crossing over’ ?

Question 61

Cell division starts from