Quick Review Flashcards - Click to flip and test your knowledge!
Question
The _____ is defined as the structural and functional unit of life.
Answer
cell
Question
What is the primary way that the majority of organisms start their life cycle?
Answer
As a single cell.
Question
According to the postulates of cell theory, where do all living beings arise from?
Answer
Pre-existing cells.
Question
Term: Unicellular organisms
Answer
Definition: Living organisms made up of only a single cell. Example: Amoeba.
Question
List three examples of unicellular organisms mentioned in the text.
Answer
Amoeba, Paramecium, and Chlamydomonas.
Question
Term: Multicellular organisms
Answer
Definition: Organisms made up of millions or billions of cells. Example: Humans.
Question
List three examples of multicellular organisms mentioned in the text.
Answer
Volvox, rose, and mosquito.
Question
How many different types of cells are approximately found in an average-sized adult human?
Answer
200
Question
What is the approximate total number of cells in the human body?
Answer
$37.2$ trillion
Question
Approximately how many nerve cells are found in the human brain cortex?
Answer
100 billion
Question
What is the approximate number of red blood cells in the human body?
Answer
25 trillion
Question
Identify the smallest cells found in the human body.
Answer
Red blood cells.
Question
What is the longest type of cell found in the human body?
Answer
Nerve cells.
Question
What is currently considered the largest single cell of the living world?
Answer
An ostrich egg.
Question
How does the biconcave and disc-shaped structure of human red blood cells aid their function?
Answer
It allows for easy passage through narrow blood capillaries.
Question
What shape do white blood cells typically adopt to squeeze through capillary walls?
Answer
Amoeboid
Question
Which specific cell shape in plant leaves allows for the opening and closing of stomata?
Answer
Bean-shaped guard cells.
Question
The cell membrane (plasma membrane) is primarily composed of _____.
Answer
lipoproteins
Question
Concept: Semi-permeable membrane
Answer
Definition: A membrane that allows only certain substances to pass through while preventing others.
Question
What is the primary chemical component of the plant cell wall?
Answer
Cellulose
Question
How does the permeability of the cell wall differ from the cell membrane?
Answer
The cell wall is freely permeable, whereas the cell membrane is semi-permeable.
Question
Which cell structure provides rigidity and a definite shape to plant cells?
Answer
The cell wall.
Question
The living part of the cell contained within the cell membrane, excluding the nucleus, is the _____.
Answer
cytoplasm
Question
What is the term for the liquid medium of the cytoplasm that remains after organelles are removed?
Answer
Cytosol
Question
What collective term describes the living parts of a cell, including the cytoplasm and the nucleus?
Answer
Protoplasm
Question
Identify the double-layered membrane that surrounds the nucleus.
Answer
Nuclear membrane
Question
What is the function of nucleoli found within the nucleus?
Answer
They produce ribosomes.
Question
During cell division, chromatin fibres condense into short thick structures called _____.
Answer
chromosomes
Question
What are the non-living parts of a cell collectively called?
Answer
Cell inclusions
Question
Which organelle acts as a supportive framework for the cell and synthesises proteins and fats?
Answer
Endoplasmic reticulum (ER)
Question
What distinguishes Rough Endoplasmic Reticulum (RER) from Smooth Endoplasmic Reticulum (SER)?
Answer
RER has ribosomes attached to its surface, while SER does not.
Question
The inner wall of a mitochondrion is thrown into numerous folds called _____.
Answer
cristae
Question
What is the primary function of mitochondria?
Answer
Release of energy from pyruvic acid in the form of ATP.
Question
Which organelle is responsible for the formation of the acrosome in sperm cells?
Answer
Golgi apparatus
Question
What is the specific name for the Golgi apparatus in plant cells?
Answer
Dictyosomes
Question
What is the sole function of ribosomes in a cell?
Answer
Protein synthesis.
Question
Why are lysosomes often referred to as 'suicide bags'?
Answer
They contain enzymes that destroy the cell's own damaged or old organelles.
Question
Which organelle, found only in animal cells, initiates and regulates cell division?
Answer
Centrosome
Question
Identify the green plastids that contain chlorophyll and trap solar energy for photosynthesis.
Answer
Chloroplasts
Question
What is the function of leucoplasts in plant cells?
Answer
They store starch and have no pigment.
Question
Which plastids are responsible for imparting colours to flowers and fruits?
Answer
Chromoplasts
Question
What is the membrane that covers a vacuole called?
Answer
Tonoplast
Question
What role do vacuoles play in plant cells regarding structural integrity?
Answer
They provide turgidity by pressing against the cell wall.
Question
Which plant pigments, providing violet-blue colours, are found within vacuoles?
Answer
Anthocyanins
Question
How does the size of vacuoles typically differ between plant and animal cells?
Answer
Plant cells have large and prominent vacuoles, while animal cells have small and temporary ones.
Question
What are 'granules' in the context of cell inclusions?
Answer
Small particles that store food substances like starch (plants) or glycogen (animals).
Question
In the onion peel experiment, which solutions are commonly used to stain the material to make the nucleus distinct?
Answer
Iodine or eosin solution.
Question
Where is the nucleus typically positioned in most plant cells, such as those in an onion peel?
Answer
Towards one side of the cell.
Question
What happens to an Amoeba if its nucleus is removed?
Answer
The Amoeba dies.
Question
If a nucleus from one Amoeba is transplanted into an enucleated Amoeba, what is the outcome for the recipient?
Answer
The recipient survives and divides.
Question
Why is the nucleus considered the 'master' of the cell?
Answer
It regulates all cell functions and contains hereditary information.