Cells in Animals and Plants Flashcards
Define magnification
How much larger an image is compared to the real object
Define resolution
The degree at which two objects can be seen as two separate objects rather than one
What is the equation for magnification?
Magnification = Image/Actual
How do you convert micrometers into millimeters?
Divide by 1000
How do you convert millimeters into micrometers?
Multiply by 1000
Name two types of microscope
Light and electron
Which type of microscope has a higher resolution?
Electron
Which type of microscope has a higher magnification?
Electron
What is a eukaryotic cell?
A cell containing a nucleus and other membrane-bound organelles
What is a prokaryotic cell?
A cell which does not contain a nucleus or other membrane-bound organelles
Give an example of a eukaryotic cell
Plant, animal, yeast
Give an example of a prokaryotic cell
Bacteria
State the function of the nucleus
Controls the cell, contains DNA
State the function of the cytoplasm
Water-based, where most chemical reactions occur
State the function of the cell membrane
Controls which substances enter and leave the cell
State the function of the mitochondria
Carry out respiration to release energy
State the function of the chloroplast
Absorb sunlight to carry out photosynthesis
State the function of the cell wall
Provides strength and support to the cell
State the function of the ribosomes
Protein synthesis
State the function of the vacuole
Stores cell sap - a mixture of sugar and salt
Give three examples of specialised animal cells
Sperm, muscle, and nerve cells
Give three examples of specialised plant cells
Root hair cell, palisade cell, xylem, and phloem
How is a sperm cell adapted to swim to the egg?
Tail for movement
How is a nerve cell adapted to carry messages?
Long
How is a muscle cell adapted to contract and relax?
Cells can get shorter or longer
How is a root hair cell adapted to absorb water?
Root hair gives a large surface area
How is a palisade cell adapted to carry out photosynthesis?
Contains many chloroplasts which contain chlorophyll
How are xylem and phloem adapted to transport substances around the plant?
Form long, hollow tubes
Define diffusion
The movement of particles from an area of high concentration to an area of low concentration
Explain why temperature affects the rate of diffusion
Higher temp. means that particles have more kinetic energy and move faster.
State how concentration gradient affects the rate of diffusion
Greater concentration gradient speeds up diffusion
State how surface area affects the rate of diffusion
Larger surface area speeds up diffusion
Define osmosis
The movement of water from an area of high water concentration to an area of low water concentration across a partially permeable membrane
What is a partially permeable membrane?
A membrane which only allows certain substances to pass through (usually small molecules such as water)
What happens to a plant cell if placed in pure water? (hypotonic solution)
Water moves in to the cell by osmosis and the cell becomes turgid (normal for a plant cell)
What happens to an animal cell if placed in pure water? (hypotonic solution)
Water moves in to the cell by osmosis and the cell bursts
What happens to a plant cell if placed in a concentrated salt solution? (hypertonic solution)
Water moves out of the cell by osmosis and the cell becomes plasmolysed
What happens to an animal cell if placed in a concentrated salt solution? (hypertonic solution)
Water moves out of the cell by osmosis and the cell shrivels
What happens to a plant cell if placed in a dilute salt solution? (isotonic solution)
There is no net movement of water so the cell is flaccid
What happens to an animal cell if placed in a dilute salt solution? (isotonic solution)
There is no net movement of water so the cell is normal
Define active transport
The movement of particles from an area of low concentration to an area of high concentration (against a concentration gradient) which requires energy
What are carrier proteins?
Proteins in the cell membrane which carry substances from one side of the cell to the other using energy to change shape.
Give an example of where active transport occurs in plants
In the roots, minerals are absorbed by active transport
Give an example of where active transport occurs in animals
In the small intestine, glucose is absorbed by active transport
State the two types of cell division, spelled correctly!
Mitosis and meiosis
What is the purpose of mitosis?
Growth and repair
What is the purpose of meiosis?
Production of gametes/sex cells
What is a haploid cell?
A cell with half the normal number of chromosomes
What is a diploid cell?
A cell with the normal number of chromosomes
How many daughter cells are produced during mitosis?
2
How many daughter cells are produced during meiosis?
4
Which type of cell division produces genetically identical daughter cells?
Mitosis
Which type of cell division produces genetically different daughter cells?
Meiosis
