Extra Credit Quiz: Unit 4 Exam Review

What are the components of DNA?

• Amino acids, ribose sugar, phosphate group, uracil

• deoxyribose sugar, phosphate group, nitrogenous base

• Fatty acids, glucose, phosphate group, adenine

• Monosaccharide, ribose sugar, sulfate group, cytosine

Answer explanation

DNA is composed of deoxyribose sugar, a phosphate group, and nitrogenous bases (adenine, thymine, cytosine, guanine). The correct choice accurately lists these essential components.

Which bases pair together in DNA?

• B) A with G and T with C

• C) A with C and T with G

• D) G with T and A with C

• A) A with T and G with C

Answer explanation

In DNA, adenine (A) pairs with thymine (T) and guanine (G) pairs with cytosine (C). This base pairing is essential for the structure and function of DNA, making option A the correct choice.

If the DNA code is TGAC, what would the complementary strand be?

• ATGC

• CGAT

• GCTA

• ACTG

Answer explanation

The DNA strand pairs are A-T and C-G. For TGAC, the complementary bases are A (for T), C (for G), T (for A), and G (for C), resulting in ACTG as the complementary strand.

What are genes?

• Proteins that build muscles

• Segments of DNA that determine traits

• Cells that carry oxygen

• Organs that digest food

Answer explanation

Genes are segments of DNA that carry the instructions for determining traits in living organisms, making them fundamental to heredity and biological functions.

Tags

NGSS.HS-LS3-2

NGSS.HS-LS3-1

Traits are only inherited from parents and cannot be affected by the environment.

• True

• False

Answer explanation

The statement is false because traits can be influenced by environmental factors, such as diet and lifestyle, in addition to being inherited from parents.

Tags

NGSS.HS-LS3-2

NGSS.HS-LS3-1

NGSS.HS-LS4-5

What is the correct order of terms from smallest to largest?

• Nucleus → Chromosome → DNA → Gene

• Gene → Chromosome → DNA → Nucleus

• DNA → Gene → Chromosome → Nucleus

• Gene → DNA → Chromosome → Nucleus

Answer explanation

The correct order from smallest to largest is Gene → DNA → Chromosome → Nucleus. A gene is a segment of DNA, which is packaged into chromosomes, and chromosomes are found within the nucleus of a cell.

Tags

NGSS.HS-LS3-1

How many chromosomes do humans have in every cell?

• 23

• 44

• 46

• 48

Answer explanation

Humans have 46 chromosomes in each cell, organized into 23 pairs. This includes 22 pairs of autosomes and 1 pair of sex chromosomes, making 46 the correct answer.

Tags

NGSS.HS-LS1-1

What is a mutation?

• A type of cell division that produces gametes

• Changes in the bases of genes/DNA

• A process by which plants make their own food

• A method of asexual reproduction in bacteria

Answer explanation

A mutation refers to changes in the bases of genes or DNA, which can lead to variations in traits. This distinguishes it from other processes like cell division or photosynthesis.

Tags

NGSS.HS-LS3-2

NGSS.HS-LS4-2

Mutations can be...

• helpful

• harmful

• be neutral (have no effect)

• all answers are possibilities for mutations

Answer explanation

Mutations can indeed be helpful, harmful, or neutral. Therefore, the correct answer is that all these possibilities exist for mutations, making 'all answers are possibilities for mutations' the right choice.

Tags

NGSS.HS-LS3-2

NGSS.HS-LS4-2

If a DNA code is changed, what is the result?

• There is no effect on the organism

• The protein that was supposed to be made can change (which changes the trait)

• The DNA repairs itself instantly

• The organism always dies immediately

Answer explanation

A change in the DNA code can lead to alterations in the protein produced, which may affect the organism's traits. This is why the correct answer is that the protein can change, impacting the organism's characteristics.

Tags

NGSS.HS-LS3-2

NGSS.HS-LS1-1