Topic 1 - Key Concepts In Biology (UNFINISHED) Flashcards
State two types of cell
Eukaryotic (plant and animal) and prokaryotic
Difference between eukaryotic and prokaryotic cells
Eukaryotic cells contain a nucleus and membrane-bound organelles. Prokaryotic cells don’t.
Components found in both plant and animal cells
Nucleus
Cell Membrane
Mitochondria
Cytoplasm
Ribosomes
How is genetic information stored in a eukaryotic cell?
Within the nucleus, arranged in chromosomes
What are 2 functions of the nucleus
Storing genetic information and controlling cellular activities
Structure of the cytoplasm
Fluid component of the cell.
Contains organelles, enzymes and dissolved ions and nutrients
Function of the cytoplasm
Site of reactions in the cell e.g first stage of respiration
Function of cell membrane
Controls the exit and entry of materials in and out of the cell
Function of the mitochondria
Site of later stages of respiration in which ATP is produced
Function of ribosomes
Joins amino acids in a specific order during translation
Organelles found in plant cells only
Large, permanent vacuole
Cell wall
Chloroplasts
What’s the cell wall made of?
Cellulose
Function of the cell wall
Provides strength
Prevents the cell bursting when water enters the cell by osmosis
What does the permanent vacuole contain
A solution of salts, sugars and organic acids
Function of the permanent vacuole
Supports the cell, maintaining its turgidity
Function of the chloroplasts
Site of photosynthesis
Why do chloroplasts appear green under a light microscope
Contain chlorophyll, which is a green pigment
Organelles found in prokaryotic cells
Chromosomal DNA
Plasmid DNA
Cell Wall
Cell Membrane
Ribosomes
Flagella
How is genetic information stored in a prokaryotic cell
Found free within the cytoplasm as:
Chromosomal DNA (large loop of circular DNA)
Plasmid DNA
What are plasmids
Small, circular loops of DNA found free in the cytoplasm and separate from the main DNA.
Carry genes that provide genetic advantages e.g antibiotic resistance
What is a prokaryotic cell wall made of
Pepsi
Peptidoglycan
What is a flagellum?
Long, rotating, ‘whip-like’ protrusion.
It allows bacteria to move
What is a haploid cell
A cell that contains a single copy of each chromosome (half the number of chromosomes) e.g 23 in humans
What is a diploid cell
A cell that contains two copies of each chromosome (full set of chromosomes) e.g 46 in humans
What are gametes?
Reproductive cells (e.g sperm and egg cells). They are haploid.
Sexual reproduction in terms of chromosome number
Two haploid gametes fuse.
embryo has two chromosomes for each gene and two copies of each allele. Therefore, it’s diploid.
