HESI A2 BIOLOGY TEST 1

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HESI A2 BIOLOGY TEST 1

Actual Qs and Ans Expert-Verified Explanation

This Exam contains:

-Guarantee passing score -38 Questions and Answers -format set of multiple-choice -Expert-Verified Explanation

Question 1: The fundamental unit of biology?

Answer:

Cell

Question 2: Microtubules that can be used to move the cell?

Answer:

Flagella

Question 3: Nucleus function?

Answer:

Nucleus - stores DNA

Question 4: Polymers of which of the following make up proteins?

Answer:

Amino acids

Question 5: 5 steps of Mitosis

Answer:

MITOSIS

Stage 1 - Prophase:

This is the first and longest stage of mitosis. The cell's chromosomes become visibly separate with each duplicated chromosome having two sister chromatids. The centrioles separate and move to opposite ends of the cell.

Stage 2 - Prometaphase:

The nuclear envelope begins to disappear, and the chromosomes begin to attach to the growing spindle.

Stage 3 - Metaphase:

All the chromosomes line up in the middle of the cell. This line is called the metaphase plate.

Stage 4 - Anaphase:

The sister chromatids separate into individual chromosomes and are pulled apart. Note that the separated chromatids are now each considered individual chromosomes.

Stage 5 - Telophase:

The chromosomes gather on each side of the cell as it begins to pinch. In animal cells, this pinching is called a cleavage furrow. In plant cells, this division is called a cell plate.

Question 6: How are plant cells different from animal cells?

Answer:

Plant cells have a cell wall; Animal cells do not have a cell wall Question 7: Meiosis 2 explanation:

Answer:

Prophase II:

In each of the two daughter cells, the chromosomes condense again into X-shaped structures. The membrane around the nucleus in each daughter cell disappears. Another meiotic spindle forms.

Metaphase II:

In each of the two daughter cells, the chromosomes line up in the middle of the cell along a line called the metaphase plate. Fibers on the meiotic spindle attach to each of the sister chromatids.

Anaphase II:

The sister chromatids are pulled apart by the meiotic spindle and brought to opposite ends of the cell.The separated chromatids are now individual chromosomes, just like mitosis.

Telophase II:

The chromosomes gather together at opposite ends of the cell. A membrane forms around each set of chromosomes, forming two new nuclei. This is the end of meiosis.; however, cell division is not complete without undergoing one more round of cytokinesis. The two daughter cells pinch in the middle and split, yielding four daughter cells each with a half set of chromosomes (this makes them haploid cells). In males, these four cells are sperm cells. In females, one of these cells becomes an egg. A sperm cell will then fertilize an egg cell to produce a new organism.

Question 8: What is the first step of cellular respiration when glucose is converted to pyruvate?

Answer:

Glycolysis Question 9: In the hierarchic system of classification, which of the following is least inclusive?

Answer:

Family

Question 10: What is Meiosis?

Answer:

The process that determines how reproductive cells (sex cells) divide in sexually reproducing organisms.Meiosis is a process where a single parent cell divides twice to produce four daughter cells. These four daughter cells (called haploid cells) have only half of the chromosomes of the parent cell. Meiosis produces our sex cells, called gametes (sperm in males and eggs in females).

Question 11: What is Mitosis?

Answer:

a type of asexual reproduction where a single cell divides into two identical daughter cells. The major purpose of mitosis is to replace worn out cells.Question 12: Before Meiosis:

Answer:

Interphase:

The chromosomes in the parent cell are duplicated, and the cell prepares for division. This parent cell now has a full set of chromosomes (46 chromosomes in human sex cells), making it a diploid cell (diploid means a full set of chromosomes).

Question 13: Where in the cell does active transport take place?

Answer:

Plasma membrane

Question 14: What describes the molecular structure of water?

Answer:

Two hydrogen atoms covalently bonded to one oxygen atom

Question 15: What is the primary reason cells undergo

mitosis ?

Answer:

Mitosis produces cells for growth and to replace worn out cells.

Question 16: What is the role of water in photosynthesis?

Answer:

Supply electrons in the light reactions Question 17: What correctly identifies the difference between saturated and unsaturated fats?

Answer:

Unsaturated fats contain one or more double bonds in their hydrocarbon tail, while saturated fats contain no double bonds.Question 18: During which phase of cell reproduction do the cell's chromosomes line up along the middle of the cell?

Answer:

Metaphase Question 19: Meiosis 1 explanation:

Answer:

Interphase:

The chromosomes in the parent cell are duplicated, and the cell prepares for division. This parent cell now has a full set of chromosomes (46 chromosomes in human sex cells), making it a diploid cell (diploid means a full set of chromosomes).

MEIOSIS I

Prophase I:

The chromosomes copied during interphase condense into X-shaped structures of two identical chromatids. These chromosomes then partner up to create homologous pairs (one chromosome from the father and one from the mother). The homologous pairs exchange bits of DNA in a process called crossing over, resulting in increased genetic variation. At the end of prophase I, the nuclear envelope (also called the nuclear membrane) breaks down.

Metaphase I:

The homologous pairs of chromosomes line up in the middle of the cell along a line called the