7-Science-Genetics-StudyGuide2

Question 1

chromosomes

Answer 1

a single tightly wound DNA strand

Question 2

DNA

Answer 2

Contains all of the info that an organism needs to grow and function

Question 3

Genes

Answer 3

Sections or segments of DNA

Question 4

Mutation

Answer 4

A change in DNA

Question 5

Incomplete Dominance

Answer 5

One gene is not completely dominant of another (red gene+white gene= pink snapdragon)

Question 6

Co-dominance

Answer 6

Two genes share dominance

Question 7

Carrier

Answer 7

A person heterozygous for a recessive genetic condition

Question 8

If two homozygous plants are bred (one green and one albino) what is the ratio of dominant/green to recessive/albino? (Punnet Square)

Answer 8

4:0

Question 9

What is the ratio of dominant:recessive traits when two heterozygous plants (see prior question) are bred? (Punnet Square)

Answer 9

3:1

Question 10

For the ration of 3:1 green to albino plants, what fraction was green?

Answer 10

3/4

Question 11

Why do unicellular organisms divide?

Answer 11

To reproduce

Question 12

Why do multicellular organisms divide?

Answer 12

To grow and replace old/dead cells

Question 13

Where is the genetic info in a cell?

Answer 13

Nucleus

Question 14

When do chromosomes appear in a cell?

Answer 14

During cell division

Question 15

What happens to the chromosome number in a cell before it divides? Why?

Answer 15

It copies the DNA so that the chromosome number is maintained in the new cells?

Question 16

How many chromosomes are in each human body cell?

Answer 16

46

Question 17

Describe the shape of DNA.

Answer 17

Like a twisted ladder, a double helix

Question 18

What is the backbone (side of the ladder) of DNA?

Answer 18

Sugar (deoxyribose) and phosphate molecules

Question 19

What are the “ladder rungs” of DNA made of?

Answer 19

Nitrogen bases

Question 20

What does tymine pair with?

Answer 20

Adenine

Question 21

What does guannine pair with?

Answer 21

Cytosine

Question 22

Why do DNA bases pair a certain way?

Answer 22

The bases fit like puzzle pieces, only chemically bond one way

Question 23

What are sex cells?

Answer 23

Sperm and Egg

Question 24

Why do sex cells have half the normal amount of chromosomes?

Answer 24

They combine to form 46 chromosomes in a zygote

Question 25

What sex chromosomes do females have? Males?

Answer 25

F: XX M: XY

Question 26

What is a karyotype and why is it used?

Answer 26

Photograph of a person's chromosomes that are cut out, paired and arranged by size; used to examine chromosomes (genes, number, ext.)

Question 27

If a mutation occurs in a sperm or egg cell, what could happen?

Answer 27

If it was involved in fertilization, the child will inherit that mutation

Question 28

Favorable mutations depend on the...

Answer 28

environment

Question 29

List example of following mutations: Helpful; Harmful; Neutral.

Answer 29

Helpful: antibiotic resistance in bacteria Harmful: cancer/genetic condition Neutral: Blue Eyes?

Question 30

In nature vs. nurture, what environmental factor were we testing?

Answer 30

Sunlight

Question 31

List 4 environmental constants:

Answer 31

Temperature, amount of water, germinating paper, space for growth.

Question 32

What is the expected ratio of green to albino under normal conditions?

Answer 32

3:1

Question 33

Can heredity alone ensure a healthy organism?

Answer 33

No. Organisms, like plants, also rely on environmental factors (like water) for proper growth.

Question 34

Can the environment alone ensure a healthy organism?

Answer 34

No. Some organisms carry mutations that affect normal growth and development.

Question 35

List 4 environmental factors that could influence human development and health:

Answer 35

Nutrition, exercise, medical care, exposure to pathogens, sleep, ect.

Question 36

Which critter characteristic showed incomplete dominance (real life example too)?

Answer 36

Nose length, snapdragons (red+white=pink)

Question 37

Which critter characteristic showed incomplete dominance (real life ex. too)?

Answer 37

spikes, AB blood

Question 38

Which critter characteristic was influenced by the environment

Answer 38

Tail style, weight, height, intelligence

Question 39

Which parent's contribution determines the child's sex?

Answer 39

male

Question 40

...conditions have carriers.

Answer 40

recessive

Question 41

A carrier's genotype is always...

Answer 41

heterozygous

Question 42

Why will children of a carrier and a person without alleles for a condition never have the condition

Answer 42

Punnet Square, carrier conditions are always recessive, and all of the kids will get a dominant "normal" allele

Question 43

Mom: A Dad: A, what are the kid's possible blood types?

Answer 43

A or O

Question 44

Mom: AB Dad: O, what are the kid's possible blood types?

Answer 44

A or B

Question 45

Mom: AB Dad: AB, what are the kid's possible blood types?

Answer 45

A, B, or AB