Unit 4a Study Guide

Question 1

Differentiate between somatic cells & germ cells

Answer 1

-Somatic- body cells, made up of most of your body tissues and organs
-Germ- Found in reproductive organs, develop into gametes, DNA can be passed onto offspring

Question 2

How many chromosomes are contained in human somatic cells?

Answer 2

46

Question 3

Name the male gamete

Answer 3

Sperm cells

Question 4

what is the term for female gamete?

Answer 4

Ova (eggs)

Question 5

How many chromosomes are contained in a human gamete?

Answer 5

23

Question 6

What are homologous chromosomes?

Answer 6

Has the same genes but a different code

Question 7

What gender is a person whose nuclei contain one x and one y chromosomes? (XY)

Answer 7

Male

Question 8

What gender is a person whose nuclei contain two x chromosomes? (XX)

Answer 8

Female

Question 9

Which contains MORE genes- an x chromosomes or a y chromosome?

Answer 9

X Chromosome

Question 10

What is the term for the fusion of an egg cell & a sperm cell?

Answer 10

Fertilization

Question 11

Differentiate between diploid (2n) & haploid (n) cells

Answer 11

Diploid (2n)- has two copies of each chromosomes while haploid (n) has only one copy

Question 12

Are somatic cells diploid or haploid?

Answer 12

Diploid

Question 13

Why is it important that gametes are haploid?

Answer 13

When the sperm and egg cell fuse together, the cell will have 46 chromosomes

Question 14

What type of division does germ cells undergo in order to produce gametes?

Answer 14

Miosis

Question 15

How many cells are produced by mitosis?

Answer 15

2

Question 16

How many cells are produced by meiosis

Answer 16

4

Question 17

What is gametogenesis?

Answer 17

Production of gametes

Question 18

What are polar bodies?

Answer 18

One of the four cells produced by meiosis will become an egg. The egg will receive most of the organelles. The other cells will go on to become polar bodies

Question 19

Why is genetic variation a good thing for a species?

Answer 19

Helps them adapt to new environments or survive

Question 20

what happens when crossing over occurs during meiosis?

Answer 20

Exchange of chromosome segments between homologous chromosomes during prophase 1 of meiosis 1. This results in recombination

Question 21

What is gene linkage?

Answer 21

Genes located close together can be inherited together

Question 22

What stage must happen before humans are able to reproduce?

Answer 22

Puberty

Question 23

Where are the human egg cells produced?

Answer 23

Ovaries

Question 24

What is the main female hormone that controls reproduction?

Answer 24

Estrogen

Question 25

What happens to a human egg once it leaves and ovary?

Answer 25

Enters the fallopian tube

Question 26

In what organ will a fertilized egg develop into a baby?

Answer 26

Uterus

Question 27

Where are human sperm produced?

Answer 27

Testicles

Question 28

What is the main male hormone that controls reproduction?

Answer 28

Testosterone

Question 29

What is the term for that cell that forms when an egg and sperm unites?

Answer 29

Zygote

Question 30

What is the name for the fluid-filled sac that protects a developing embryo?

Answer 30

Amniotic sac

Question 31

What is the role of the placenta?

Answer 31

Connects the mother and the embryo, allowing the exchange of oxygen, nutrients, and waste

Question 32

How are the embryo & the placenta connected?

Answer 32

Umbilical cord

Question 33

A human pregnancy typically last about ___ months

Answer 33

9

Question 34

What are the three major stages of a human pregnancy called?

Answer 34

Trimesters

Question 35

Why is it challenging for scientist to study DNA?

Answer 35

While DNA is a large molecule its far too small to see

Question 36

what do scientist use to cut up DNA into manageable sections?

Answer 36

Enzymes

Question 37

What is a restriction map?

Answer 37

DNA fingerprint

Question 38

what is a polymerase chain reaction (PCR)?

Answer 38

Technique that produces millions-billions of copies of a specific DNA sequence in just a few hours

Question 39

List three great uses for DNA fingerprinting

Answer 39

-Solving crimes
-Prove family relationships
-Identify genetically engineered crops

Question 40

What is a clone?

Answer 40

Genetically identical copy of a gene or an entire organism

Question 41

Why are bacteria that reproduced via binary fission clones of each other?

Answer 41

Exact same DNA

Question 42

What are some issues associated with the cloning of mammals?

Answer 42

-Unhealthy
-Age quickly
-Environmental factors

Question 43

Why is genetic engineering possible?

Answer 43

All organism share the same basic nucleotides

Question 44

What is recombinant DNA?

Answer 44

DNA that contains genes from more than one organism

Question 45

What does it mean when a organism is transgenic?

Answer 45

Organism that has one of more genes from another organism inserted in its genome

Question 46

What are some issues that many people have with genetically modified (GM) plants?

Answer 46

-Not enough research
-some genes can cause allergic reactions
-Consequences to the environment
-Genetic diversity is decreased

Question 47

What is a genome?

Answer 47

All organisms genetic information

Question 48

What is genomics?

Answer 48

Study of genomes

Question 49

what is the purpose of the Human Genome project?

Answer 49

It mapped and sequenced all the DNA base pairs of human chromosomes. It identified all genes within a sequence

Question 50

Why is genetic screening sometimes controversial?

Answer 50

-People become anxious
-False positives or false negatives
-Risk of social stigmatization
-Privacy issues

Question 51

What occurs when a person undergoes gene therapy?

Answer 51

The replacement of a defective or missing gene or the addition of a new gene into a persons genome to treat a disease