1. plant cells Flashcards
prokaryotes
- No nucleus
- Smaller
- lack membrane bound organelles such as mitochondria, chloroplasts, Golgi apparatus, and endoplasmic reticulum
- Reproduce through binary fission, where the cell divides into two identical daughter cells.
- Bacteria and Archaea
Eukaryotes
-Yes nucleus
-Larger
-lack membrane bound organelles including the nucleus, mitochondria, chloroplasts (in plants), endoplasmic reticulum, and others
-Undergo more complex cell division processes, including mitosis (for somatic cell division) and meiosis (for gamete formation in sexual reproduction)
-plants, animals, fungi, and protists.
cell membrane
-Acts as a selective barrier, controlling what enters and exits the cell
-composed of a lipid bilayer with embedded proteins, allowing for selective permeability
nucleus
-The control center of the cell, containing the cell’s genetic material (DNA) organized into chromosomes
-regulates gene expression and cell division.
-Nucleolus: Located inside the nucleus, it is responsible for producing ribosomes.
cytoplasm
-jelly-like substance that fills the cell and surrounds the organelles
-provides a medium for biochemical reactions and helps in cellular processes like metabolism.
ribosome
-Sites of protein synthesis
-floating in the cytoplasm or attached to the rough endoplasmic reticulum (ER).
endoplasmic reticulum
-Rough ER: Covered with ribosomes, the rough ER is involved in the synthesis and modification of proteins.
-Smooth ER: Lacks ribosomes and is involved in the synthesis of lipids, metabolism of carbohydrates, and detoxification of drugs and poisons
golgi apparatus
-Processes, sorts, and ships proteins and lipids received from the ER.
- modifies molecules by adding sugars or phosphate groups
mitochondria
-The powerhouse of the cell, responsible for generating ATP (the cell’s energy currency) through cellular respiration.
vacuoles
-Storage sacs within the cell
-the central vacuole maintains turgor pressure and stores nutrients and waste products
chloroplast
-Site of photosynthesis, where light energy is converted into chemical energy in the form of glucose
-contain the green pigment chlorophyll.
cytoskeleton
-Provides structural support for the cell and plays a role in cell movement and division.
-composed of microtubules, actin filaments, and intermediate filaments.
cell wall
-Provides additional structural support and protection
-made of cellulose
peroxisomes
-Involved in the breakdown of fatty acids and the detoxification of harmful substances
-contain enzymes that produce and degrade hydrogen peroxide.
plasmodesmata
-Channels that allow communication and transport of materials between plant cells.
structure of plasmodesmata
microscopic channels that traverse the cell walls of adjacent plant cells, allowing for the direct transfer of materials between them.
function of plasmodesmata
-cell communication between adjacent cells allowing coordination
-direct exchange of cytoplasmic materials, including ions, small molecules (like sugars and amino acids), and signaling molecules (like hormones).
-enable the movement of nutrients, water, and other essential compounds between cells, which is crucial for maintaining cellular function and homeostasis
phospholipids
-Composed of hydrophilic heads and hydrophobic tails that form a double layer.
membrane proteins
-Integral and peripheral proteins that facilitate transport, communication, and structural support.
carbohydrates
-Attached to proteins and lipids, involved in cell recognition and signaling.
contents of vacuole
-water
-potassium, sodium, calcium, and chloride, which help regulate osmotic balance and pH within the cell.
- Sugars and other carbohydrates can be stored in vacuoles, serving as energy reserves
-Waste products, toxins, and by-products of metabolism, preventing them from interfering with cellular processes.
tonoplast
-membrane that surrounds the vacuole in plant cells
-separates the vacuolar contents from the cytoplasm.
-selectively permeable
-maintaining turgor pressure
composition of chromosome
-long, thread-like structure made of DNA and proteins that carries genetic information
-composed of DNA tightly coiled around proteins called histones. This combination of DNA and proteins is known as chromatin.
chromatin
-allowing for gene expression and DNA replication.
-During cell division, chromatin condenses into distinct chromosomes to ensure accurate segregation of genetic material.
cell division
-Mitosis: process of cell division that results in two identical daughter cells for growth and repair
-Meiosis: specialized division that produces four genetically diverse gametes for sexual reproduction, reducing the chromosome number by half.
chromoplast
-Responsible for photosynthesis, converting light energy into chemical energy stored in glucose.
-Chlorophyll: Located in the thylakoid membranes
leucoplast
-Involved in the storage of starch, lipids, and proteins.
-non-pigmented
-found in non-photosynthetic tissues such as roots and tubers.
-Starch Grains: They often contain starch granules, which are compact structures made of amylose and amylopectin.
