Cells and cell processes：練習問題

A student observes a specimen under a light microscope. If the eyepiece has a magnification of \(15\times\) and the objective lens being used has a magnification of \(20\times\), what is the total magnification of the image?

Based on the specialized structure shown in the diagram, how is this specific plant cell adapted to perform its primary function in the roots?

Which of the following identifies the correct sequence of organelles that a protein, such as a digestive enzyme, passes through from its synthesis to its secretion out of the cell?

What is the basic functional and structural unit of all living organisms?

A scientist discovers a new unicellular organism. Detailed analysis reveals it possesses 70S ribosomes, a circular DNA molecule not enclosed in a nuclear envelope, and a cell wall composed of peptidoglycan. In which of the following groups should this organism be classified?

A sunflower turns its flower head to follow the movement of the sun across the sky during the day. Which of the seven characteristics of living things does this observation best demonstrate?

In multicellular organisms, cells are organized into increasingly complex structures. Arrange the following components in the correct order of biological organization, from the simplest level to the most complex level: digestive system, epithelial cell, stomach, stomach lining (epithelial tissue).

Consider a spherical cell with an initial radius of \(r\). If the radius of the cell increases to \(2r\), calculate the factor by which the volume of the cell increases and explain how this change affects the surface area to volume ratio (\(SA:V\)) of the cell.

A student uses a microscope to study a slide of onion epidermal cells. The student observes several structures as shown in the diagram.

(a) Name the rigid outer layer labeled A.
(b) Name the large, fluid-filled organelle labeled B that stores water and mineral salts.
(c) State why chloroplasts are typically absent in these onion epidermal cells.

A student is investigating the levels of organization in the human body. They use a light microscope to examine a sample of heart tissue.

(a) If the eyepiece magnification is \(10\times\) and the objective lens magnification is \(40\times\), calculate the total magnification.
(b) Refer to the diagram provided. Identify the level of organization indicated by the bracket.
(c) Arrange the following levels of biological organization in order from the simplest to the most complex: Organ, Cell, Organism, Tissue, Organ system.