Question 1

All living things are composed of cells. Which of the following is a feature that all cells have in common?

Accepted Answer

They all have a plasma membrane enclosing their contents.

Question 2

A biological membrane has two basic components: one is polar and one is non-polar. How are these components arranged in the plasma membrane?

Accepted Answer

The polar heads face the aqueous environment on both sides, while the non-polar tails face each other in the interior.

Question 3

Which of the following is NOT a basic difference between prokaryotic and eukaryotic cells?

Accepted Answer

Prokaryotic cells have a nucleus, while eukaryotic cells do not.

Question 4

A DNA molecule is double stranded with nitrogenous bases (A, T, C, G) in the middle. How are the bases paired?

Accepted Answer

A pairs with T, and C pairs with G.

Question 5

What property of the nitrogenous bases in DNA determines the structure of a protein?

Accepted Answer

The order (sequence) of the bases encodes the amino acid sequence of the protein.

Question 6

You have 46 chromosomes in almost every cell. How many copies of each chromosome do you have, and in which type of chromosome might this not be true?

Accepted Answer

Two copies of each chromosome; not true in gametes (sperm or egg cells).

Question 7

In which cells are there only one copy of each chromosome (haploid cells)?

Accepted Answer

Gametes (sperm and egg cells)

Question 8

Most cell division in your body creates two identical cells. What is this process called?

Accepted Answer

Mitosis

Question 9

Where does meiosis occur, how many cells are formed, and how do the chromosomes in these cells compare to the original cell?

Accepted Answer

Occurs in reproductive organs, forms four cells, each with half the number of chromosomes as the original.

Question 10

The PTC tasting gene is on chromosome 7. If tasting is a dominant trait and you are heterozygous, what proportion of your gametes will contain the PTC tasting allele?

Accepted Answer

$$\frac{1}{2}$$

Question 11

How do evolutionary biologists explain why genes in different species have very similar nucleotide sequences?

Accepted Answer

Because they share a common ancestor and have inherited similar genes.

Question 12

Which of the following lists the three domains of life?

Accepted Answer

Bacteria, Archaea, Eukarya

Question 13

For eukaryotes, what are the three largest kingdoms?

Accepted Answer

Plantae, Fungi, Animalia

Question 14

What are eukaryotes that do not fit neatly into the three main kingdoms called?

Accepted Answer

Protists

Question 15

What is a photosynthetic protist called?

Accepted Answer

Alga

Question 16

Which of the following is a key difference between fungi and animals?

Accepted Answer

Fungi have cell walls made of chitin, while animals lack cell walls.

Question 17

A mutation occurs in the gene coding for a membrane protein, causing the non-polar region to become polar. What is the most likely effect on the protein's position in the membrane?

Accepted Answer

The protein may no longer embed properly in the membrane, affecting its function.

Question 18

If a cell undergoes mitosis but not cytokinesis, what will be the result?

Accepted Answer

One cell with two nuclei.

Question 19

A scientist discovers a new organism with a single circular chromosome, no nucleus, and ribosomes. To which domain does this organism most likely belong?

Accepted Answer

Bacteria

Question 20

During meiosis, homologous chromosomes separate during which phase, and what is the result for the chromosome number in the resulting cells?

Accepted Answer

Anaphase I; the chromosome number is halved.

General Biology: Cell Structure, Genetics, and Domains of Life Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard